JEE Main Session 2 26th June 2022 Shift 2 Question Paper and Answer Key

JEE Main Session 2 26th June 2022 Shift 2

PHYSICS

Section-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii)   Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. The dimension of mutual inductance is :

(A) [ML2T–2A–1]

(B) [ML2T–3A–1]

(C) [ML2T–2A–2]

(D) [ML2T–3A–2]

Answer: (C)

2. In the arrangement shown in figure a1, a2, a3 and a4 are the accelerations of masses m1, m2, m3 and m4 Which of the following relation is true for this arrangement?

(A) 4a1 + 2a2 + a3 + a4 = 0

(B) a1 + 4a2 + 3a3 + a4 = 0

(C) a1 + 4a2 + 3a3 + 2a4 = 0

(D) 2a1 + 2a2 + 3a3 + a4 = 0

Answer: (A)

3. Arrange the four graphs in descending order of total work done; where W1, W2, W3 and W4 are the work done corresponding to figure a, b, c and d respectively.

(A) W3> W2> W1> W4

(B) W3> W2> W4> W1

(C) W2> W3> W4> W1

(D) W2> W3> W1> W4

Answer: (A)

4. Solid spherical ball is rolling on a frictionless horizontal plane surface about its axis of symmetry. The ratio of rotational kinetic energy of the ball to its total kinetic energy is :-

(A)  2/5

(B)  2/7

(C)  1/5

(D)  7/10

Answer: (B)

5. Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: If we move from poles to equator, the direction of acceleration due to gravity of earth always points towards the center of earth without any variation in its magnitude. 

Reason R: At equator, the direction of acceleration due to the gravity is towards the center of earth.  In the light of above statements, choose the correct answer from the options given below :

(A) Both A and R are true and R is the correct explanation of A.

(B) Both A and R are true but R is NOT the correct explanation of A.

(C) A is true but R is false.

(D) A is false but R is true.

Answer: (D)

6. If ρ is the density and η is coefficient of viscosity of fluid which flows with a speed v in the pipe of diameter d, the correct formula for Reynolds number Re is:

Answer: (C)

7. A flask contains argon and oxygen in the ratio of 3:2 in mass and the mixture is kept at 27°C. The ratio of their average kinetic energy per molecule respectively will be :

(A) 3 : 2

(B) 9 : 4

(C) 2 : 3

(D) 1 : 1

Answer: (D)

8. The charge on capacitor of capacitance 15 μF in the figure given below is

(A)  60 μc

(B)  130μc

(C)  260μc

(D)  585μc

Answer: (A)

9. A parallel plate capacitor with plate area A and plate separation d=2 m has a capacitance of 4 μ The new capacitance of the system if half of the space between them is filled with a dielectric material of dielectric constant K=3 (as shown in figure) will be :

(A)  2 μF

(B)  32μF

(C)  6μF

(D)  8μF

Answer: (C)

10. Sixty four conducting drops each of radius 0.02 m and each carrying a charge of 5 μC are combined to form a bigger drop. The ratio of surface density of bigger drop to the smaller drop will be :

(A)  1 : 4

(B)  4 : 1

(C)  1 : 8

(D)  8 : 1

Answer: (B)

11. The equivalent resistance between points A and B in the given network is :

(A)  65 Ω

(B)  20 Ω

(C)  5 Ω

(D)  2 Ω

Answer: (C)

12. A bar magnet having a magnetic moment of 2.0 × 105 JT–1, is placed along the direction of uniform magnetic field of magnitude B= 14 × 10–5 The work done in rotating the magnet slowly through 60° from the direction of field is :

(A)  14 J

(B)  8.4 J

(C)  4 J

(D)  1.4 J

Answer: (A)

13. Two coils of self inductance L1 and L2 are connected in series combination having mutual inductance of the coils as M. The equivalent self inductance of the combination will be :

(A) 

(B)  L1 + L2 + M

(C)  L1 + L2 + 2M

(D)  L1 + L2 – 2M

Answer: (D)

14. A metallic conductor of length 1m rotates in a vertical plane parallel to east-west direction about one of its end with angular velocity 5 rad/s. If the horizontal component of earth’s magnetic field is 0.2 × 10–4 T, then emf induced between the two ends of the conductor is :

(A)  5 μV

(B)  50μV

(C)  5mV

(D)  50 mV

Answer: (B)

15. Which is the correct ascending order of wavelengths?

(A) λvisible < λX-ray < λgamma-ray < λmicrowave

(B) λgamma-ray < λX-ray < λvisible < λmicrowave

(C) λX-ray < λgamma-ra y< λvisible < λmicrowave

(D) λmicrowave < λvisible < λgamma-ray < λX-ray

Answer: (B)

16. For a specific wavelength 670 nm of light coming from a galaxy moving with velocity v, the observed wavelength is 670.7 nm.

(A) 3 × 108ms–1

(B) 3 × 1010ms–1

(C) 3.13 × 105ms–1

(D) 4.48 × 105ms–1

Answer: (C)

17. A metal surface is illuminated by a radiation of wavelength 4500 Å. The rejected photo-electron enters a constant magnetic field of 2 mT making an angle of 90° with the magnetic field. If it starts revolving in a circular path of radius 2 mm, the work function of the metal is approximately:

(A) 1.36 eV

(B) 1.69 eV

(C) 2.78 eV

(D) 2.23 eV

Answer: (A)

18. A radioactive nucleus can decay by two different processes. Half-life for the first process is 3.0 hours while it is 4.5 hours for the second process. The effective half-life of the nucleus will be:

(A) 3.75 hours

(B) 0.56 hours

(C) 0.26 hours

(D) 1.80 hours

Answer: (D)

19. The positive feedback is required by an amplifier to act an oscillator. The feedback here means:

(A) External input is necessary to sustain ac signal in output

(B) A portion of the output power is returned back to the input

(C) Feedback can be achieved by LR network

(D) The base-collector junction must be forward biased

Answer: (B)

20. A sinusoidal wave y(t) = 40sin(10 × 106 πt) is amplitude modulated by another sinusoidal wave x(t) = 20sin(1000πt). The amplitude of minimum frequency component of modulated signal is:

(A)  0.5

(B)  0.25

(C)  20

(D)  10

Answer: (D)

SECTION-B

21. A ball is projected vertically upward with an initial velocity of 50 ms–1 at t = 0 s. At t = 2 s, another ball is projected vertically upward with same velocity. At t = _____s, second ball will meet the first ball.

(g = 10 ms2)

Answer: (6)

22. A batsman hits back a ball of mass 0.4 kg straight in the direction of the bowler without changing its initial speed of 15 ms–1. The impulse imparted to the ball is _________ Ns.

Answer: (12)

23. A system to 10 balls each of mass 2 kg are connected via massless and unstretchable string. The system is allowed to slip over the edge of a smooth table as shown in figure. Tension on the string between the 7th and 8th ball is ______ N when 6th ball just leaves the table.

Answer: (36)

24. A geyser heats water flowing at a rate of 2.0 kg per minute from 30°C to 70°C. If geyser operates on a gas burner, the rate of combustion of fuel will be ____________g min–1

[Heat of combustion = 8 × 103Jg–1

Specific heat of water = 4.2 Jg–1 °C–1

Answer: (42)

25. A heat engine operates with the cold reservoir at temperature 324 K. The minimum temperature of the hot reservoir, if the heat engine takes 300 J heat from the hot reservoir and delivers 180 J heat to the cold reservoir per cycle, is ___________K.

Answer: (540)

26. A set of 20 tuning forks is arranged in a series of increasing frequencies. If each fork gives 4 beats with respect to the preceding fork and the frequency of the last fork is twice the frequency of the first, then the frequency of last fork is _______Hz.

Answer: (152)

27. Two 10 cm long, straight wires, each carrying a current of 5 A are kept parallel to each other. If each wire experienced a force of 10–5 N, then separation between the wires is _____ cm.

Answer: (5)

28. A small bulb is placed at the bottom of a tank containing water to a depth of √7 m. The refractive index of water is 4/3. The area of the surface of water through which light from the bulb can emerge out is xπ m2. The value of x is ________.

Answer: (9)

29. A travelling microscope is used to determine the refractive index of a glass slab. If 40 divisions are there in 1 cm on main scale and 50 Vernier scale divisions are equal to 49 main scale divisions, then least count of the travelling microscope is _______× 10–6

Answer: (5)

30. The stopping potential for photoelectrons emitted from a surface illuminated by light of wavelength 6630 Å is 0.42 V. If the threshold frequency is x × 1013/s, where x is _________ (nearest integer).

(Given, speed of light = 3 × 108 m/s, Planck’s constant = 6.63 × 10–34Js)

Answer: (35)

CHEMISTRY

SECTION-A

1. The number of radial and angular nodes in 4d orbital are. respectively

(A) 1 and 2

(B) 3 and 2

(C) 1 and 0

(D) 2 and 1

Answer: (A)

2. Match List I with List II

Choose the most appropriate answer from the options given below :

(A) A-III, B-IV, C-II, D-I

(B) A-III, B-II, C-I, D-IV

(C) A-IV, B-III, C-I, D-II

(D) A-IV, B-II, C-III, D-I

Answer: (C)

3. Which of the following elements is considered as a metalloid?

(A) Sc

(B) Pb

(C) Bi

(D) Te

Answer: (D)

4. The role of depressants in ‘Froth Floation method’ is to

(A) Selectively prevent one component of the ore from coming to the froth

(B) Reduce the consumption of oil for froth formation

(C) Stabilize the froth

(D) Enhance non-wettability of the mineral particles.

Answer: (A)

5. Boiling of hard water is helpful in removing the temporary hardness by converting calcium hydrogen carbonate and magnesium hydrogen carbonate to

(A) CaCO3 and Mg(OH)2

(B) CaCO3 and MgCO3

(C) Ca(OH)2 and MgCO3

(D) Ca(OH)2 and Mg(OH)2

Answer: (A)

6. s-block element which cannot be qualitatively confirmed by the flame test is

(A)  Li

(B)  Na

(C)  Rb

(D)  Be

Answer: (D)

7. The oxide which contains an odd electron at the nitrogen atom is

(A)  N2O

(B)  NO2

(C)  N2O3

(D)  N2O5

Answer: (B)

8. Which one of the following is an example of disproportionation reaction?

Answer: (A)

9. The most common oxidation state of Lanthanoid elements is +3. Which of the following is likely to deviate easily from +3 oxidation state?

(A) Ce(At. No. 58)

(B) La (At. No. 57)

(C) Lu (At. No. 71)

(D) Gd(At. No. 64)

Answer: (A)

10. The measured BOD values for four different water samples (A-D) are as follows:

A = 3 ppm: B=18 ppm: C-21 ppm: D=4 ppm. The water samples which can be called as highly polluted with organic wastes, are

(A) A and B

(B) A and D

(C) B and C

(D) B and D

Answer: (C)

11. The correct order of nucleophilicity is

Answer: (D)

12. Oxidation of toluene to Benzaldehyde can be easily carried out with which of the following reagents?

(A) CrO3/acetic acid, H3O+

(B) CrO3/acetic anhydride, H3O+

(C) KMnO4/HCl, H3O+

(D) CO/HCl, anhydrous AlCl3

Answer: (B)

13. The major product in the following reaction

Answer: (A)

14. Halogenation of which one of the following will yield m-substituted product with respect to methyl group as a major product?

Answer: (C)

15. The reagent, from the following, which converts benzoic acid to benzaldehyde in one step is

(A)  LiAlH4

(B)  KMnO4

(C)  MnO

(D)  NaBH4

Answer: (C)

16. The final product ‘A’ in the following reaction sequence

Answer: (A)

17. Which statement is NOT correct for p-toluenesulphonyl chloride?

(A) It is known as Hinsberg’s reagent

(B) It is used to distinguish primary and secondary amines

(C) On treatment with secondary amine, it leads to a product, that is soluble in alkali

(D) It doesn’t react with tertiary amines

Answer: (C)

18. The final product ‘C’ in the following series of reactions

Answer: (C)

19. Which of the following is NOT an example of synthetic detergent?

Answer: (B)

20. Which one of the following is a water soluble vitamin, that is not excreted easily?

(A) Vitamin B2

(B) Vitamin B1

(C) Vitamin B6

(D) Vitamin B12

Answer: (D)

SECTION-B

21. CNG is an important transportation fuel. When 100 g CNG is mixed with 208 g oxygen in vehicles, it leads to the formation of CO2 and H2O and produced large quantity of heat during this combustion, then the amount of carbon dioxide, produced in grams is _____. [nearest integer]

Answer: (143)

22. In a solid AB, A atoms are in ccp arrangement and B atoms occupy all the octahedral sites. If two atoms from the opposite faces are removed, then the resultant stoichiometry of the compound is AxBy. The value of x is ___________. [nearest integer]

Answer: (3)

23. Amongst SF4, XeF4, CF4 and H2O, the number of species with two lone pair of electrons is _____.

Answer: (2)

24. A fish swimming in water body when taken out from the water body is covered with a film of water of weight 36 g. When it is subjected to cooking at 100 °C, then the internal energy for vaporization in kJ mol–1 is ________. [nearest integer]

[Assume steam to be an ideal gas. Given ΔvapH for water at 373 K and 1 bar is 41.1 kJ mol–1; R = 8.31 J K–1mol–1]

Answer: (38)

25. The osmotic pressure exerted by a solution prepared by dissolving 2.0 g of protein of molar mass 60 kg mol–1 in 200 mL of water at 27°C is _________ Pa. [Integer value]

(use R = 0.083 L bar mol–1 K–1)

Answer: (415)

26. 40% of HI undergoes decomposition to H2 and I2 at 300 K. ΔG° for this decomposition reaction at one atmosphere pressure is ________ J mol–1. [nearest integer]

(Use R = 8.31 J K–1mol–1; log 2 = 0.3010, ln 10 = 2.3, log 3 = 0.477)

Answer: (2735)

27. Cu(s) + Sn2+ (0.001 M) → Cu2+ (0.01M) + Sn(s) The Gibbs free energy change for the above reaction at 298 K is x × 10–1 kJ mol–1; The value of x is______. [nearest integer]

[Given :  F = 96500C mol1]

Answer: (983)

28. Catalyst A reduces the activation energy for a reaction by 10 kJ mol–1 at 300 K. The ratio of rate constants, is ex. The value of x is _______. [nearest integer]

[Assume that the pre-exponential factor is same in both the cases.

Given R = 8.31 J K–1mol–1]

Answer: (4)

29. Reaction of [Co(H2O)6]2+ with excess ammonia and in the presence of oxygen results into a diamagnetic product. Number of electrons present in t2g–orbitals of the product is _______ .

Answer: (6)

30. The moles of methane required to produce 81 g of water after complete combustion is ______ × 10–2 [nearest integer]

Answer: (225)

MATHEMATICS

SECTION A

1. Let f : ℝ→ℝ be defined as f(x) = x – 1 and g : ℝ− {1, −1} →ℝ be defined as

Then the function fog is:

(A) One-one but not onto

(B) Onto but not one-one

(C) Both one-one and onto

(D) Neither one-one nor onto

Answer: (D)

2. If the system of equations αx + y + z = 5, x + 2y + 3z = 4, x + 3y +5z = β has infinitely many solutions, then the ordered pair (α, β) is equal to:

(A) (1, –3)

(B) (–1, 3)

(C) (1, 3)

(D) (–1, –3)

Answer: (C)

3. If  and  then A/B is equal to:

(A)  11/9

(B)  1

(C)  −11/9

(D)  −11/3

Answer: (C)

4. is equal to :

(A)  1/3

(B)  1/4

(C)  1/6

(D)  1/12

Answer: (C)

5. Let f(x) = min {1, 1 + x sin x}, 0 ≤ x ≤ 2π. If m is the number of points, where f is not differentiable, and n is the number of points, where f is not continuous, then the ordered pair (m, n) is equal to

(A) (2, 0)

(B) (1, 0)

(C) (1, 1)

(D) (2, 1)

Answer: (B)

6. Consider a cuboid of sides 2x, 4x and 5x and a closed hemisphere of radius r. If the sum of their surface areas is a constant k, then the ratio x : r, for which the sum of their volumes is maximum, is

(A) 2 : 5

(B) 19 : 45

(C) 3 : 8

(D) 19 : 15

Answer: (B)

7. The area of the region bounded by y2 = 8x and y2 = 16(3 – x) is equal to

(A)  32/3

(B)  40/3

(C)  16

(D)  19

Answer: (C)

8. If  g(1) = 0, then g(1/2) is equal to :

Answer: (A)

9. If y = y(x) is the solution of the differential equation  y(1) = 0, then the local maximum value of the function z(x) = x2y(x)-ex, x ∈ R is :

(A)  1 – e

(B)  0

(C)  1/2

(D)  4/e – e

Answer: (D)

10. If the solution of the differential equation  satisfies y(0) = 0, then the value of y(2) is __________.

(A)  −1

(B)  1

(C)  0

(D)  e

Answer: (C)

11. If m is the slope of a common tangent to the curves  and x2 + y2 = 12, then 12m2 is equal to :

(A)  6

(B)  9

(C)  10

(D)  12

Answer: (B)

12. The locus of the mid-point of the line segment joining the point (4, 3) and the points on the ellipse x2 + 2y2 = 4 is an ellipse with eccentricity:

(A)  √3/2

(B)  1/2√2

(C)  1/√2

(D)  1/2

Answer: (C)

13. The normal to the hyperbola  at the point (8, 3√3) on it passes through the point:

(A)  (15, −2√3)

(B)  (9, 2√3)

(C)  (−1, 9√3)

(D)  (−1, 6√3)

Answer: (C)

14. If the plane 2x + y – 5z = 0 is rotated about its line of intersection with the plane 3x – y + 4z – 7 = 0 by an angle of π/2, then the plane after the rotation passes through the point:

(A) (2, –2, 0)

(B) (–2, 2, 0)

(C) (1, 0, 2)

(D) (–1, 0, –2)

Answer: (C)

15. If the lines  and  are co-planar, then the distance of the plane containing these two lines from the point (α, 0, 0) is :

(A)  2/9

(B)  2/11

(C)  4/11

(D)  2

Answer: (B)

16. Let  and  be three given vectors. Let  be a vector in the plane of  whose projection on  is equal to

(A)  6

(B)  7

(C)  8

(D)  9

Answer: (D)

17. The mean and standard deviation of 50 observations are 15 and 2 respectively. It was found that one incorrect observation was taken such that the sum of correct and incorrect observations is 70. If the correct mean is 16, then the correct variance is equal to :

(A)  10

(B)  36

(C)  43

(D)  60

Answer: (C)

18. 16 sin(20°) sin(40°) sin(80°) is equal to :

(A) √3

(B) 2√3

(C) 3

(D) 4√3

Answer: (B)

19. If the inverse trigonometric functions take principal values, then  is equal to:

(A)  0

(B)  π/4

(C)  π/3

(D)  π/6

Answer: (C)

20. Let r ∈ {p, q, ~p, ~q} be such that the logical statement r ∨ (~p) ⇒ (p ∧ q) ∨ r is a tautology. Then r is equal to :

(A) p

(B) q

(C) ~p

(D) ~q

Answer: (C)

SECTION-B

21. Let f: ℝ → ℝ satisfy f(x + y) = 2x f(y) + 4y f(x), ∀ x, y ∈ ℝ. If f(2) = 3, then  is equal to ___.

Answer: (248)

22. Let p and q be two real numbers such that p + q = 3 and p4 + q4 = 369. Then  is equal to ________.

Answer: (4)

23. If z2 + z + 1 = 0, z ∈ ℂ, then  is equal to ________.

Answer: (2)

24. Let  Y = aI + βX + γX2 and Z = α2I – αβX + (β2 – αγ)X2, α, β, γ ∈ ℝ. If  then (α–β + γ)2 is equal to ___________.

Answer: (100)

25. The total number of 3-digit numbers, whose greatest common divisor with 36 is 2, is ________

Answer: (150)

26. If (40C0) + (41C1) + (42C2) + …+(60C20 m and n are coprime, then m + n is equal to _________.

Answer: (102)

27. If a1 (> 0), a2, a3, a4, a5 are in a G.P., a2 + a4 = 2a3 + 1 and 3a2 + a3 = 2a4, then a2 + a4 + 2a5 is equal to _______.

Answer: (40)

28. If integral  is equal to _______.

Answer: (3)

29. Let a line L1 be tangent to the hyperbola  and let L2 be the line passing through the origin and perpendicular to L1. If the locus of the point of intersection of L1 and L2 is (x2 + y2)2 = αx2 + βy2, then α + β is equal to _________.

Answer: (12)

30. If the probability that a randomly chosen 6-digit number formed by using digits 1 and 8 only is a multiple of 21 is p, then 96 p is equal to ________.

Answer: (33)

JEE Main Session 2 25th June 2022 Shift 2 Question Paper and Answer Key

JEE Main Session 2 25th June 2022 Shift-2

PHYSICS

Section-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii)   Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Two identical balls A and B thrown with same velocity ’u’ at two different angles with horizontal attained the same range R. If A and B reached the maximum height h1 and h2 respectively, then 

Reason R: Product of said heights.

Choose the correct answer :

(A) Both A and R are true and R is the correct explanation of A.

(B) Both A and R are true but R is NOT the correct explanation of A.

(C) A is true but R is false.

(D) A is false but R is true.

Answer: (A)

2. Two buses P and Q start from a point at the same time and move in a straight line and their positions are represented by XP(t) = αt + βt2 and XQ(t) = ft – t2. At what time, both the buses have same velocity?

Answer: (D)

3. A disc with a flat small bottom beaker placed on it at a distance R from its center is revolving about an axis passing through the center and perpendicular to its plane with an angular velocity ω. The coefficient of static friction between the bottom of the beaker and the surface of the disc is μ. The beaker will revolve with the disc if :

Answer: (B)

4. A solid metallic cube having total surface area 24 m2 is uniformly heated. If its temperature is increased by 10°C, calculate the increase in volume of the cube.

(Given α = 5.0 × 10–4 °C–1).

(A) 2.4 × 106 cm3

(B) 1.2 × 105 cm3

(C) 6.0 × 104 cm3

(D) 4.8 × 105 cm3

Answer: (B)

5. A copper block of mass 5.0 kg is heated to a temperature of 500°C and is placed on a large ice block. What is the maximum amount of ice that can melt?

[Specific heat of copper : 0.39 J g–1 °C–1 and latent heat of fusion of water : 335 J g–1]

(A)  1.5 kg

(B)  5.8 kg

(C)  2.9 kg

(D)  3.8 kg

Answer: (C)

6. The ratio of specific heats (CP/CV) in terms of degree of freedom (f) is given by:

Answer: (B)

7. For a particle in uniform circular motion, the acceleration a at any point P(R, θ) on the circular path of radius R is (when θ is measured from the positive x-axis and v is uniform speed):

Answer: (C)

8. Two metallic plates form a parallel plate capacitor. The distance between the plates is ‘d’. A metal sheet of thickness d/2 and of area equal to area of each plate is introduced between the plates. What will be the ratio of the new capacitance to the original capacitance of the capacitor?

(A)  2 : 1

(B)  1 : 2

(C)  1 : 4

(D)  4 : 1

Answer: (A)

9. Two cells of same emf but different internal resistances r1 and r2 are connected in series with a resistance R. The value of resistance R, for which the potential difference across second cell is zero, is:

(A)  r2 – r1

(B)  r1 – r2

(C)  r1

(D)  r2

Answer: (A)

10. Given below are two statements:

Statement-I : Susceptibilities of paramagnetic and ferromagnetic substances increase with decrease in temperature.

Statement-II : Diamagnetism is a result of orbital motions of electrons developing magnetic moments opposite to the applied magnetic field.

Choose the correct answer from the options given below:-

(A) Both Statement-I and Statement-II are true

(B) Both Statement-I and Statement-II are false

(C) Statement-I is true but Statement-II is false

(D) Statement-I is false but Statement-II is true

Answer: (A)

11. A long solenoid carrying a current produces a magnetic field B along its axis. If the current is doubled and the number of turns per cm is halved, the new value of magnetic field will be equal to

(A)  B

(B)  2B

(C)  4B

(D)  B/2

Answer: (A)

12. A sinusoidal voltage V(t) = 210 sin 3000 t volt is applied to a series LCR circuit in which L = 10 mH, C = 25 μF and R = 100 Ω. The phase difference (Φ) between the applied voltage and resultant current will be:

(A)  tan1 (0.17)

(B)  tan1 (9.46)

(C)  tan1 (0.30)

(D)  tan1 (13.33)

Answer: (A)

13. The electromagnetic waves travel in a medium at a speed of 2.0 × 108 m/s. The relative permeability of the medium is 1.0. The relative permittivity of the medium will be:

(A)  2.25

(B)  4.25

(C)  6.25

(D)  8.25

Answer: (A)

14. The interference pattern is obtained with two coherent light sources of intensity ratio 4 : 1. And the ratio  Then, the value of x will be equal to :

(A)  3

(B)  4

(C)  2

(D)  1

Answer: (B)

15. A light whose electric field vectors are completely removed by using a good polaroid, allowed to incident on the surface of the prism at Brewster’s angle. Choose the most suitable option for the phenomenon related to the prism.

(A) Reflected and refracted rays will be perpendicular to each other.

(B) Wave will propagate along the surface of prism.

(C) No refraction, and there will be total reflection of light.

(D) No reflection, and there will be total transmission of light.

Answer: (D)

16. A proton, a neutron, an electron and an α-particle have same energy. If λp, λn, λe and λα are the de Broglie’s wavelengths of proton, neutron, electron and α particle respectively, then choose the correct relation from the following:

(A) λp = λne> λα

(B) λαnpe

(C) λep = λn> λα

(D) λe = λp = λn = λα

Answer: (B)

17. Which of the following figure represents the variation of  with ln A (if R = radius of a nucleus and A = its mass number)

Answer: (B)

18. Identify the logic operation performed by the given circuit:

(A)  AND gate

(B)  ORgate

(C)  NORgate

(D)  NANDgate

Answer: (A)

19. Match List I with List II

Choose the correct answer from the following options :

(A) A-IV, B-III, C-II, D-I

(B) A-I, B-IV, C-II, D-III

(C) A-IV, B-II, C-III, D-I

(D) A-I, B-II, C-III, D-IV

Answer: (B)

20. If n represents the actual number of deflections in a converted galvanometer of resistance G and shunt resistance S. Then the total current I when its figure of merit is K will be

Answer: (D)

SECTION-B

21. For z = a2x3y1/2, where ‘a‘ is a constant. If percentage error in measurement of ‘x‘ and ‘y’ are 4% and 12%, respectively, then the percentage error for ‘z‘ will be _______ %.

Answer: (18)

22. A curved in a level road has a radius 75 m. The maximum speed of a car turning this curved road can be 30 m/s without skidding. If radius of curved road is changed to 48 m and the coefficient of friction between the tyres and the road remains same, then maximum allowed speed would be ______ m/s.

Answer: (24)

23. A block of mass 200 g is kept stationary on a smooth inclined plane by applying a minimum horizontal force F = √xN as shown in figure. The value of x = _________.

Answer: (12)

24. Moment of Inertia (M.I.) of four bodies having same mass ‘M‘ and radius ‘2R‘ are as follows :

I1 = M.I. of solid sphere about its diameter

I2 = M.I. of solid cylinder about its axis

I3 = M.I. of solid circular disc about its diameter.

I4 = M.I. of thin circular ring about its diameter

If 2(I2 + I3) + I4 = x⋅ I1 then the value of x will be _________.

Answer: (5)

25. Two satellites S1 and S2 are revolving in circular orbits around a planet with radius R1 = 3200 km and R2 = 800 km respectively. The ratio of speed of satellite S1 to the speed of satellite S2 in their respective orbits would be 1/x where x =

Answer: (2)

26. When a gas filled in a closed vessel is heated by raising the temperature by 1ºC, its pressure increases by 0.4%. The initial temperature of the gas is _____ K.

Answer: (250)

27. 27 identical drops are charged at 22 V each. They combine to form a bigger drop. The potential of the bigger drop will be ______ V.

Answer: (198)

28. The length of a given cylindrical wire is increased to double of its original length. The percentage increase in the resistance of the wire will be ______%.

Answer: (300)

29. In a series LCR circuit, the inductance, capacitance and resistance are L = 100 mH, C = 100 μF and R = 10 Ω respectively. They are connected to an AC source of voltage 220 V and frequency of 50 Hz. The approximate value of current in the circuit will be ______ A.

Answer: (22)

30. In an experiment of CE configuration of n–p–n transistor, the transfer characteristics are observed as given in figure.

If the input resistance is 200 Ω and output resistance is 60 Ω, the voltage gain in this experiment will be_________.

Answer: (15)

CHEMISTRY

SECTION-A

1. The minimum energy that must be possessed by photons in order to produce the photoelectric effect with platinum metal is

[Given The threshold frequency of platinum is 1.3 × 1015 s–1 and h = 6.6 × 10–34Js.]

(A) 3.21 × 10–14 J

(B) 6.24 × 10–16 J

(C) 8.58 × 10–19 J

(D) 9.76 × 10–20 J

Answer: (C)

2. At 25°C and 1 atm pressure, the enthalpy of combustion of benzene (I) and acetylene (g) are –3268 kJ mol–1 and –1300 kJ mol–1, respectively. The change in enthalpy for the reaction 3C2H2(g) → C6H6(I), is

(A) +324 kJ mol–1

(B) +632 kJ mol–1

(C) –632 kJ mol–1

(D) –732 kJ mo1–1

Answer: (C)

3. Solute A associates in water. When 0.7 g of solute A is dissolved in 42.0 gof water, it depresses the freezing point by 0.2°C. The percentage association of solute A in water is :

[Given : Molar mass of A = 93 g mol–1. Molal depression constant of water is 1.86 K kg mol–1.]

(A)  50%

(B)  60%

(C)  70%

(D)  80%

Answer: (D)

4. The Ksp for bismuth sulphide (Bi2S3) is 1.08 × 10–73. The solubility of Bi2S3 in mol L–1 at 298 K is

(A) 1.0 × 10–15

(B) 2.7 × 10–12

(C) 3.2 × 10–10

(D) 4.2 × 10–8

Answer: (A)

5. Match List I with List II.

Choose the correct answer from the options given below.

(A) A-II, B-III, C-I, D-IV

(B) A-II, B-III, C-IV, D-I

(C) A-III, B-II, C-IV, D-I

(D) A-III, B-II, C-I, D-IV

Answer: (B)

6. The correct order of electron gain enthalpies of Cl, F, Te and Po is

(A) F <Cl<Te< Po

(B) Po <Te< F <Cl

(C) Te< Po <Cl< F

(D) Cl< F <Te< Po

Answer: (B)

7. Given below are two statements.

Statement-I: During electrolytic refining, blister copper deposits precious metals.

Statement-II: In the process of obtaining pure copper by electrolysis method, copper blister is used to make the anode.

In the light of the above statements, choose the correct answer from the options given below.

(A) Both Statement-I and Statement-II are true.

(B) Both Statement-I and Statement-II are false.

(C) Statement-I is true but Statement II is false.

(D) Statement-I is false but Statement-II is true

Answer: (A)

8. Given below are two statements one is labelled as Assertion A and the other is labelled as Reason R:

Assertion A: The amphoteric nature of water is explained by using Lewis acid/base concept

Reason R: Water acts as an acid with NH3 and as a base with H2S.

In the light of the above statements choose the correct answer from the options given below:

(A) Both A and R are true and R is the correct explanation of A.

(B) Both A and R are true but R is NOT the correct explanation of A.

(C) A is true but R is false.

(D) A is false but R is true.

Answer: (D)

9. The correct order of reduction potentials of the following pairs is

(A)  Cl2/Cl

(B)  I2/I

(C)  Na+/Na

(D)  Li+/Li

Choose the correct answer from the options given below:

(A) A > C > B > D > E

(B) A > B > C > D > E

(C) A > C > B > E > D

(D) A > B > C > E > D

Answer: (A)

10. The number of bridged oxygen atoms present in compound B formed from the following reactions is

(A)  0

(B)  1

(C)  2

(D)  3

Answer: (A)

11. The metal ion (in gaseous state) with lowest spin-only magnetic moment value is

(A)  V2+

(B)  Ni2+

(C)  Cr2+

(D)  Fe2+

Answer: (B)

12. Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Polluted water may have a value of BOD of the order of 17 ppm.

Reason R: BOD is a measure of oxygen required to oxidise both the bio-degradable and non-biodegradable organic material in water.

In the light of the above statements, choose the most appropriate answer from the options given below.

(A) Both A and R are correct and R is the correct explanation of A.

(B) Both A and R are correct but R is NOT the correct explanation of A.

(C) A is correct but R is not correct.

(D) A is not correct but R is correct.

Answer: (C)

13. Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: A mixture contains benzoic acid and naphthalene. The pure benzoic acid can be separated out by the use of benzene.

Reason R: Benzoic acid is soluble in hot water.

In the light of the above statements, choose the most appropriate answer from the options given below.

(A) Both A and R are true and R is the correct explanation of A.

(B) Both A and R are true but R is NOT the correct explanation of A.

(C) A is true but R is false.

(D) A is false but R is true.

Answer: (D)

14. During halogen test, sodium fusion extract is boiled with concentrated HNO3 to

(A) remove unreacted sodium

(B) decompose cyanide or sulphide of sodium

(C) extract halogen from organic compound

(D) maintain the pH of extract.

Answer: (B)

15. Amongst the following, the major product of the given chemical reaction is

Answer: (A)

16. In the given reaction

‘A’ can be

(A) Benzyl bromide

(B) Bromo benzene

(C) Cyclohexyl bromide

(D) Methyl bromide

Answer: (B)

17. Which of the following conditions or reaction sequence will NOT give acetophenone as the major product?

Answer: (C)

18. The major product formed in the following reaction, is

Answer: (D)

19. Which of the following ketone will NOT give enamine on treatment with secondary amines? [where t-Bu is –C(CH3)3]

Answer: (C)

20. An antiseptic Dettol is a mixture of two compounds ‘A’ and ‘B’ where A has 6π electrons and B has 2π electrons. What is ‘B’?

(A) Bithionol

(B) Terpineol

(C) Chloroxylenol

(D) Chloramphenicol

Answer: (B)

SECTION-B

21. A protein ‘A’ contains 0.30% of glycine (molecular weight 75). The minimum molar mass of the protein ‘A’ is _______ × 103 g mol–1 [nearest integer]

Answer: (25)

22. A rigid nitrogen tank stored inside a laboratory has a pressure of 30 atm at 06:00 am when the temperature is 27°C. At 03:00 pm, when the temperature is 45°C, the pressure in the tank will be _______ atm. [nearest integer]

Answer: (32)

23. Amongst BeF2, BF3, H2O, NH3, CCl4 and HCl, the number of molecules with non-zero net dipole moment is ______.

Answer: (3)

24. At 345 K, the half life for the decomposition of a sample of a gaseous compound initially at 55.5 kPa was 340 s. When the pressure was 27.8 kPa, the half life was found to be 170 s. The order of the reaction is ________. [integer answer]

Answer: (0)

25. A solution of Fe2(SO4)3 is electrolyzed for ‘x’ min with a current of 1.5 A to deposit 0.3482 g of Fe. The value of x is _______. [nearest integer]

Given : 1 F = 96500 C mol–1

Atomic mass of Fe = 56 g mol–1

Answer: (20)

26. Consider the following reactions:

PCl3 + H2O → A + HCl

A + H2O → B + HCl

The number of ionisable protons present in the product B is _________.

Answer: (2)

27. Amongst FeCl3.3H2O, K3[Fe(CN)6)] and [Co(NH3)6]Cl3, the spin-only magnetic moment value of the inner-orbital complex that absorbs light at shortest wavelength is _______B.M. [nearest integer]

Answer: (2)

28. The Novolac polymer has mass of 963 g. The number of monomer units present in it are

Answer: (9)

29. How many of the given compounds will give a positive Biuret test_________? Glycine, Glycylalanine, Tripeptide, Biuret.

Answer: (2)

30. The neutralization occurs when 10 mL of 0.1M acid ‘A’ is allowed to react with 30 mL of 0.05 M base M(OH)2. The basicity of the acid ‘A’ is_________.

[M is a metal]

Answer: (3)

MATHEMATICS

SECTION A

1. Let A = {x ∈ R : | x + 1 | < 2} and B = {x ∈ R : | x – 1| ≥ 2}. Then which one of the following statements is NOT true?

(A) A – B = (–1, 1)

(B) B – A = R – (–3, 1)

(C) A ⋂ B = (–3, –1]

(D) A U B = R – [1, 3)

Answer: (B)

2. Let a, b ∈ R be such that the equation ax2 – 2bx + 15 = 0 has a repeated root α. If α and β are the roots of the equation x2 – 2bx + 21 = 0, then α2 + β2 is equal to

(A)  37

(B)  58

(C)  68

(D)  92

Answer: (B)

3. Let z1 and z2 be two complex numbers such that 

Answer: (C)

4. The system of equations

–kx + 3y – 14z = 25

–15x + 4y – kz = 3

–4x + y + 3z = 4

is consistent for all k in the set

(A) R

(B) R – {–11, 13}

(C) R – {13}

(D) R – {–11, 11}

Answer: (D)

5. is equal to

(A)  1/12

(B)  −1/18

(C)  −1/12

(D)  −1/6

Answer: (A)

6. The area of the region enclosed between the parabolas y2 = 2x – 1 and y2 = 4x – 3 is

(A)  1/3

(B)  1/6

(C)  2/3

(D)  3/4

Answer: (A)

7. The coefficient of x101 in the expression (5 + x)500 + x(5 + x)499 + x2(5 + x)498 + ……+ x500, x > 0, is

(A) 501C101 (5)399

(B) 501C101 (5)400

(C) 501C100 (5)400

(D) 500C101 (5)399

Answer: (A)

8. The sum 1 + 2 ⋅ 3 + 3 ⋅ 32 + …. + 10 ⋅ 39 is equal to

Answer: (B)

9. Let P be the plane passing through the intersection of the planes  the point (2, 1, −2). Let the position vectors of the points X and Y be  Then the points

(A) X and X + Y are on the same side of P

(B) Y and Y – X are on the opposite sides of P

(C) X and Y are on the opposite sides of P

(D) X + Y and X – Y are on the same side of P

Answer: (C)

10. A circle touches both the y-axis and the line x + y = 0. Then the locus of its center is

(A)  y = √2x

(B)  x = √2y

(C)  y2 – x2 = 2xy

(D)  x2 – y2 = 2xy

Answer: (D)

11. Water is being filled at the rate of 1 cm3/sec in a right circular conical vessel (vertex downwards) of height 35 cm and diameter 14 cm. When the height of the water level is 10 cm, the rate (in cm2/sec) at which the wet conical surface area of the vessel increase, is

(A)  5

(B)  √21/5

(C)  √26/5

(D)  √26/10

Answer: (C)

12. If  then

(A)  b3 – b2, b4 – b3, b5 – b4 are in an A.P. with a common difference

(B)  are in an A.P. with common difference 2

(C)  b3 – b2, b4 – b3, b5 – b4 are in a G.P.

(D)  are in an A.P. with common difference −2

Answer: (D)

13. If y = y(x) is the solution of the differential equation  such that y(e)=e/3, then y(1) is equal to

(A)  1/3

(B)  2/3

(C)  3/2

(D)  3

Answer: (B)

14. If the angle made by the tangent at the point (x0, y0) on the curve x = 12(t + sin t cos t), y = 12(1 + sin t)2, 0 < t <π/2, with the positive x-axis is π/3, then y0 is equal to

(A)  6(3 + 2√2)

(B)  3(7 + 4√3)

(C)  27

(D)  48

Answer: (C)

15. The value of 2 sin(12°) – sin(72°) is :

Answer: (D)

16. A biased die is marked with numbers 2, 4, 8, 16, 32, 32 on its faces and the probability of getting a face with mark n is 1/n. If the die is thrown thrice, then the probability, that the sum of the numbers obtained is 48, is :

(A)  7/211

(B)  7/212

(C)  3/210

(D)  13/212

Answer: (D)

17. The negation of the Boolean expression ((~ q) ∧ p) ⇒ ((~ p) ∨ q) is logically equivalent to :

(A) p⇒ q

(B) q⇒ p

(C) ~ (p ⇒ q)

(D) ~ (q ⇒ p)

Answer: (c)

18. If the line y = 4 + kx, k > 0, is the tangent to the parabola y = x – x2 at the point P and V is the vertex of the parabola, then the slope of the line through P and V is :

(A)  3/2

(B)  26/9

(C)  5/2

(D)  23/6

Answer: (C)

19. The value of  is equal to

(A)  −π/4

(B)  −π/8

(C)  −5π/12

(D)  −4π/9

Answer: (B)

20. The line y = x + 1 meets the ellipse  at two points P and Q. If r is the radius of the circle with PQ as diameter then (3r)2 is equal to :

(A)  20

(B)  12

(C)  11

(D)  8

Answer: (A)

SECTION-B

21. Let  Then the number of elements in the set {(n, m) : n, m ∈ { 1, 2……….., 10} and nAn + mBm = I} is ____________.

Answer: (1)

22. Let f(x) = [2x2 + 1] and  where [t] is the greatest integer ≤ t. Then, in the open interval (–1, 1), the number of points where fog is discontinuous is equal to _______.

Answer: (62)

23. The value of b > 3 for which is equal to_____

Answer: (6)

24. If the sum of the co-efficients of all the positive even powers of x in the binomial expansion of  is 510 – β∙39, then β is equal to ________

Answer: (83)

25. If the mean deviation about the mean of the numbers 1, 2, 3, ….n, where n is odd, is  then n is equal to ___________.

Answer: (21)

26. Let λ ∈ R. If  is a vector such that  then  is equal to

Answer: (14)

27. The total number of three-digit numbers, with one digit repeated exactly two times, is ______.

Answer: (243)

28. Let f(x) = |(x – 1)(x2 – 2x – 3)| + x – 3, x ∈ If m and M are, respectively the number of points of local minimum and local maximum of f in the interval (0, 4), then m + M is equal to

Answer: (3)

29. Let the eccentricity of the hyperbola  If the equation of the normal at the point (8/√5, 12/5) on the hyperbola is 8√5 x + β y = λ, then λ – β is equal to _______.

Answer: (85)

30. Let l1 be the line in xy-plane with x and y intercepts 1/8 and 1/4√2 respectively and l2 be the line in zx-plane with x and z intercepts −1/8 and −1/6√3 respectively. If d is the shortest distance between the line l1 and l2, then d–2 is equal to __________.

Answer: (51)

JEE Main Session 2 24th June 2022 Shift 2 Question Paper and Answer Key

JEE MAIN Session 2 24th June 2022 Shift 2

PHYSICS

SECTION-A

IMPORTANT INSTRUCTIONS:

(1) The test is of 3 hours duration:

(2) The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i) Section-A: This section contains 20 multiple choice questions which have only one correct answer. Each question carries 4 marks for correct answer and -1 mark for wrong answer.

(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and -1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. Identify the pair of physical quantities that have same dimensions:

(A)  velocity gradient and decay constant

(B)  wien’s constant and Stefan constant

(C)  angular frequency and angular momentum

(D)  wave number and Avogadro number

Answer: (A)

2. The distance between Sun and Earth is R. The duration of year if the distance between Sun and Earth becomes 3R will be:

(A)  √3 years

(B)  3years

(C)  9years

(D)  3√3years

Answer: (D)

3. A stone of mass m, tied to a string is being whirled in a vertical circle with a uniform speed. The tension in the string is:

(A)  the same throughout the motion

(B)  minimum at the highest position of the circular path

(C)  minimum at the lowest position of the circular path

(D)  minimum when the rope is in the horizontal position

Answer: (B)

4. Two identical charged particles each having a mass 10 g and charge 2.0 × 107 C area placed on horizontal table with a separation of L between then such that they stay in limited equilibrium. If the coefficient of friction between each particle and the table is 0.25, find the value of L. [Use g = 10 ms2]

(A)  12 cm

(B)  10 cm

(C)  8 cm

(D)  5 cm

Answer: (A)

5. A Carnot engine take 5000 kcal of heat from a reservoir at 727°C and gives heat to a sink at 127°C. The work done by engine is:

(A)  3 × 106 J

(B)  Zero

(C)  12.6 × 106 J

(D)  8.4 × 106 J   

Answer: (C)

6. Two massless springs with spring constants 2 k and 2 k, carry 50 g and 100 g masses at their free ends. These two masses oscillate vertically such that their maximum velocities are equal. Then, the ratio of their respective amplitudes will be:

(A)  1 : 2

(B)  3 : 2

(C)  3 : 1

(D)  2 : 3

Answer: (B)

7. What will be the most suitable combination of three resistors A = 2Ω, B = 4Ω, C = 6Ω so that (22/3)Ω is equivalent resistance of combination?

(A)  Parallel combination of A and C connected in series with B.

(B)  Parallel combination of A and B connected in series with C.

(C)  Series combination of A and C connected in parallel with B.

(D)  Series combination of B and C connected in parallel with A.

Answer: (B)

8. The soft-iron is a suitable material for making an electromagnet. This is because soft-iron has:

(A)  low coercively and high retentively

(B)  low coercively and low permeability

(C)  high permeability and low retentively

(D)  high permeability and high retentively

Answer: (C)

9. A proton, a deuteron and anα-particle with same kinetic energy enter into a uniform magnetic field at right angle to magnetic field. The ratio of the radii of their respective circular paths is :

(A)  1 :√2 : √2

(B)  1 : 1 : √2

(C)  √2 : 1 : 1

(D)  1 :√2 : 1

Answer: (D)

10. Given below are statements:

Statement-I :The reactance of an ac circuit is zero. It is possible that the circuit contains a capacitor and inductor.

Statement-II : In ac circuit, the average poser delivered by the source never becomes zero.

In the light of the above statements, choose the correct answer from the options given below:

(A)  Both Statement I and Statement II are true.

(B)  Both Statement I and Statement II are false.

(C)  Statement I is true but statement II in false.

(D)  Statement I is false but Statement II is true.

Answer: (C)

11. Potential energy as a function of r is given by , where r is the interatomic distance, A and B are positive constants. The equilibrium distance between the two atoms will be:

(A)  (A/B)1/5

(B)  (B/A)1/5

(C)  (2A/B)1/5

(D)  (B/2A)1/5

Answer: (C)

12. An object of mass 5 kg is thrown vertically upwards from the ground. The air resistance produces a constant retarding force of 10 N throughout the motion. The ratio of time of ascent to the time of descent will be equal to : [Use g = 10 ms2]

(A)  1 : 1

(B)  √2 :√3

(C)  √3 :√2

(D)  2 : 3

Answer: (B)

13. A fly wheel is accelerated uniformly from rest and rotates through 5 rad in the first second. The angle rotated by the fly wheel in the next second, will be:

(A)  7.5 rad

(B)  15 rad

(C)  20 rad

(D)  30 rad

Answer: (B)

14. A 100 g of iron nail is hit by a 1.5 kg hammer striking at a velocity of 60 ms1. What will be the rise in the temperature of the nail if one of fourth of energy of the hammer goes into heating the nail?

[Specific heat capacity of iron = 0.42 Jg1°C1]

(A)  675°C

(B)  1600°C

(C)  160.7°C

(D)  6.75°C

Answer: (C)

15. If the charge on a capacitor is increased by 2 C, the energy stored in it increases by 44%. The original charge on the capacitor is (in C):

(A)  10

(B)  20

(C)  30

(D)  40

Answer: (A)

16. A long cylindrical volume contains a uniformly distributed charge of density ρ. The radius of cylindrical volume is R. A charge particle (q) revolves around the cylinder in a circular path. The kinetic of the particle is :

Answer: (A)

17. An electric bulb is rated as 200 W. What will be the peak magnetic field at 4 m distance produced by the radiations coming from this bulb? Consider this bulb as a point source with 3.5% efficiency.

(A)  1.19 × 108 T

(B)  1.71 × 108 T

(C)  0.84 × 108 T

(D)  3.36 × 108 T

Answer: (B)

18. The light of two different frequencies whose photons have energies 3.8 eV and 1.4 eV respectively, illuminate a metallic surface whose work function is 0.6 eV successively. The ratio of maximum speeds of emitted electrons for the two frequencies respectively will be:

(A)  1 : 1

(B)  2 : 1

(C)  4 : 1

(D)  1 : 4

Answer: (B)

19. Two light beams of intensities in the ratio of 9 : 4 are allowed to interfere. The ratio of the intensity of maxima and minima will be:

(A)  2 : 3

(B)  16 : 81

(C)  25 : 169

(D)  25 : 1

Answer: (D)

20. In Bohr’s atomic model of hydrogen, let K. P and E are the kinetic energy, potential energy and total energy of the electron respectively. Choose the correct option when the electron undergoes transitions to a higher level:

(A)  All K.P and E increase.

(B)  K decreases. P and E increase.

(C)  P decreases. K and E increase.

(D)  K increases. P and E decrease.

Answer: (B)

SECTION-B

21. A body is projected from the ground at an angle of 45° with the horizontal. Its velocity after 2s is 20 ms1. The maximum height reached by the body during its motion is ________ m. (use g = 10 ms2)

Answer: (20)

22. An antenna is placed in a dielectric medium of dielectric constant 6.25. If the maximum size of that antenna is 5.0 mm. It can radiate a signal of minimum frequency of ________ GHz.

(Given μr = 1 for dielectric medium)

Answer: (6)

23. A potentiometer wire of length 10 m and resistance 20 Ω is connected in series with a 25 V battery and an external resistance 30 Ω. A cell of emf E in secondary circuit is balanced by 25 cm long potentiometer wire. The value of E ( in volt) is x/10. The value of x is _______.

Answer: (25)

24. Two travelling waves of equal amplitudes and equal frequencies move in opposite directions along a string. They interfere to produce a stationary wave whose equation is given by 

The amplitude of the particle at x = 4/3 cm will be _______ cm.

Answer: (5)

25. In the given circuit the value of current IL will be _______ mA.

(When RL = 1kΩ)

Answer: (5)

26. A sample contains 102 kg each of two substances A and B with half lives 4 s and 8 s respectively. The ratio of then atomic weights is 1 : 2. The ratio of the amounts of A and B after 16 s is x/100. The value of x is ________.

Answer: (25)

27. A ray of light is incident at an angle of incidence 60° on the glass slab of refractive index √ After reaction, the light ray emerges out from other parallel faces and lateral shift between incident ray and emergent ray is 4√3 cm. The thickness of the glass slab is ________ cm.

Answer: (12)

28. A circular coil of 1000 turns each with area 1 m2 is rotated about its vertical diameter at the rate of one revolution per second in a uniform horizontal magnetic field of 0.07T. The maximum voltage generation will be _______ V.

Answer: (440)

29. A monoatomic gas performs a work of Q/4 where Q is the heat supplied to it. The molar heat capacity of the gas will be ________ R during this transformation.

Where R is the gas constant.

Answer: (2)

30. In an experiment to verify Newton’s law of cooling, a graph is plotted between, the temperature difference (∆T) of the water and surroundings and time as shown in figure. The initial temperature of water is taken as 80° The value of t2 as mentioned in the graph will be __________.

Answer: (16)

CHEMISTRY

SECTION-A

1. 120 of an organic compound that contains only carbon and hydrogen gives 330g of CO2 and 270g of water on complete combustion. The percentage of carbon and hydrogen, respectively are.

(A)  25 and 75

(B)  40 and 60

(C)  60 and 40

(D)  75 and 25

Answer: (D)

2. The energy of one mole of photons of radiation of wavelength 300 nm is

(Given : h = 6.63 × 1034Js, NA = 6.02 × 1023 mol1, c = 3 × 108 ms1)

(A)  235 kJ mol1

(B)  325kJ mol1

(C)  399kJ mol1

(D)  435kJ mol1

Answer: (C)

3. The correct order of bound orders of C22−, N22− and O22− is, respectively.

(A)  C22−< N22−< O22−

(B)  O22−< N22−< C22−

(C)  C22−< O22−< N22−

(D)  N22−< C22−< O22−

Answer: (B)

4. At 25°C and 1 atm pressure, the enthalpies of combustion are as given below:

The enthalpy of formation of ethane is

(A)  +54.0 kJ mol−1

(B)  −68.0 kJ mol−1

(C)  −86.0 kJ mol−1

(D)  +97.0 kJ mol−1         

Answer: (C)

5. For a first order reaction, the time required for completion of 90% reaction is ‘x’ times the half life of the reaction. The value of ‘x’ is

(Given: ln 10 = 2.303 and log 2 = 0.3010)

(A)  1.12

(B)  2.43

(C)  3.32

(D)  33.31

Answer: (C)

6. Metals generally melt at very high temperature. Amongst the following, the metal with the highest melting point will be

(A)  Hg

(B)  Ag

(C)  Ga

(D)  Cs

Answer: (B)

7. Which of the following chemical reactions represents Hall-Heroult Process?

(A)  Cr2O3 + 2Al → Al2O3 + 2Cr

(B)  2Al2O3 + 3C → 4Al + 3CO2

(C)  FeO + CO → Fe + CO2

(D) 

Answer: (B)

8. In the industrial production of which of the following, molecular hydrogen is obtained as a byproduct?

(A)  NaOH

(B)  NaCl

(C)  Na Metal

(D)  Na2CO3

Answer: (A)

9. Which one of the following compounds is used as a chemical in certain type of fire extinguishers?

(A)  Baking Soda

(B)  Soda ash

(C)  Washing Soda

(D)  Caustic Soda

Answer: (A)

10. PCl5 is well known. but NCl5 is not. Because.

(A)  nitrogen is less reactive than phosphorous.

(B)  nitrogen doesn’t have d-orbitals in its valence         shell.

(C)  catenation tendency is weaker in nitrogen than      phosphorous.

(D)  size of phosphorous is larger than nitrogen.

Answer: (B)

11. Transition metal complex with highest value of crystal field splitting (∆0) will be

(A)  [Cr(H2O)6]3+

(B)  [Mo(H2O)6]3+

(C)  [Fe(H2O)6]3+

(D)  [Os(H2O)6]3+

Answer: (D)

12. Some gases are responsible for heating of atmosphere (green house effect). Identify from the following the gaseous species which does not cause it.

(A)  CH4

(B)  O3

(C)  H2O

(D)  N2

Answer: (D)

13. Arrange the following carbocations in decreasing order of stability.

(A)  A > C > B

(B)  A > B > C

(C)  C > B > A

(D)  C > A > B

Answer: (B)

14. Given below are two statements.

Statement I: The presence of weaker π- bonds make alkenes less stable than alkanes. 

Statement II: The strength of the double bond is greater than that of carbon-carbon single bond. 

In the light of the above statements, choose the correct answer from the options given below.

(A)  Both Statement I and Statement II are correct.

(B)  Both Statement I and Statement II are incorrect.

(C)  Statement I is correct but Statement II is incorrect.

(D)  Statement I is incorrect but Statement II is correct.

Answer: (A)

15. Which of the following reagents/ reactions will convert ‘A’ to ‘B’?

(A)  PCC oxidation

(B)  Ozonolysis   

(C)  BH3,H2O2/OH followed by PCC oxidation

(D)  HBr, hydrolysis followed by oxidation by K2Cr2O7.

Answer: (C)

16. Hex-4-ene-2-ol on treatment with PCC gives ‘A’. ‘A’ on reaction with sodium hypoiodite gives ‘B’, which on further heating with soda lime gives ‘C’. The compound ‘C’ is

(A)  2- pentene

(B)  proponaldehyde

(C)  2-butene

(D)  4-methylpent-2-ene

Answer: ()

17. The conversion of propan-1-ol to n-butylamine involves the sequential addition of reagents. The correct sequential order of reagents is.

(A)  (i) SOCl2 (ii) KCN (iii) H2/Ni,Na(Hg)/C2H5OH

(B)  (i) HCl (ii) H2/Ni, Na(Hg)/C2H5OH

(C)  (i) SOCl2 (ii) KCN (iii) CH3NH2

(D)  (i) HCl (ii) CH3NH2

Answer: (A)

18. Which of the following is not an example of a condensation polymer?

(A)  Nylon 6,6

(B)  Decron

(C)  Buna-N

(D)  Silicone

Answer: (C)

19. The structure shown below is of which well-known drug molecule?

(A)  Ranitidine

(B)  Seldane

(C)  Cimetidine

(D)  Codeine

Answer: (C)

20. In the flame test of a mixture of salts, a green flame with blue centre was observed. Which one of the following cations may be present?

(A)  Cu2+

(B)  Sr2+

(C)  Ba2+

(D)  Ca2+

Answer: (A)

SECTION-B

21. At 300 K, a sample of 3.0 g of gas A occupies the same volume as 0.2 g of hydrogen at 200 K at the same pressure. The molar mass of gas A is____ g mol–1 (nearest integer) Assume that the behaviour of gases as ideal. (Given: The molar mass of hydrogen (H2) gas is 2.0 g mol–1)

Answer: (45)

22. A company dissolves ‘X’ amount of CO2 at 298 K in 1 litre of water to prepare soda water X = ______ × 103 (nearest integer)

(Given: partial pressure of CO2 at 298 K= 0.835 bar.  Henry’s law constant for CO2 at 298 K = 1.67 kbar.   Atomic mass of H,C and O is 1, 12 and 6 g mol–1, respectively)

Answer: (1221 OR 1222)

23. PCl5 dissociates as

PCl5(g) ⇌ PCl3(g) + Cl2(g)

5 moles of PCl5 are placed in a 200 litre vessel which contains 2 moles of N2 and is maintained at 600 K. The equilibrium pressure is 2.46 atm. The equilibrium constant Kp for the dissociation of PCl5 is_____ × 10–3. (nearest integer)   (Given: R = 0.082 L atm K–1mol–1 : Assume ideal gas behaviour)

Answer: (1107)

24. The resistance of conductivity cell containing 01 M KCl solution at 298 K is 1750 Ω. If the conductively of 0.01 M KCl solution at 298 K is 0.152 × 10–3 S cm–1, then the cell constant of the conductivity cell is_______× 10–3 cm–1.

Answer: (266)

25. When 200 mL of 0.2 M acetic acid is shaken with 0.6 g of wood charcoal, the final concentration of acetic acid after adsorption is 0.1 M. The mass of acetic acid adsorbed per gram of carbon is ________g.

Answer: (2)

26. (a) Baryte, (b) Galena, (c) Zinc blende and (d) Copper pyrites. How many of these minerals are sulphide based?

Answer: (3)

27. Manganese (VI) has ability to disproportionate in acidic solution. The difference in oxidation states of two ions it forms in acidic solution is __________.

Answer: (3)

28. 0.2 g of an organic compound was subjected to estimation of nitrogen by Duma’s method in which volume of N2 evolved (at STP) was found to be 22.400 mL. The percentage of nitrogen in the compound is _____. [nearest integer]

(Given : Molar mass of N2 is 28 g mol–1, Molar volume of N2 at STP : 22.4L)

Answer: (14)

29.

Consider the above reaction. The number of π electrons present in the product ‘P’ is ______

Answer: (2)

30. In alanylglycylleucylalanyvaline, the number of peptide linkages is __________.

Answer: (4)

MATHEMATICS

SECTION-A

1. Let x * y = x2 + y3 and (x * 1) * 1 = x * (1 * 1). Then a value of  is

(A)  π/4

(B)  π/3

(C)  π/2

(D)  π/6

Answer: ()

2. The sum of all the real roots of the equation (e2x – 4) (6e2x – 5ex + 1) = 0 is

(A)  loge3

(B)  −loge3

(C)  loge6

(D)  −loge6

Answer: (B)

3. Let the system of linear equations

x + y + az = 2

3x + y + z = 4

x + 2z = 1

have a unique solution (x*, y*, z*). If (α, x*), (y*, α) and (x*, –y*) are collinear points, then the sum of absolute values of all possible values of α is

(A)  4

(B)  3

(C)  2

(D)  1

Answer: (C)

4. Let x, y > 0. If x3y2 = 215, then the least value of 3x + 2y is

(A)  30

(B)  32

(C)  36

(D)  40

Answer: (D)

5. Let 

Where [t] denotes greatest integer t. If m is the number of points where f is not continuous and n is the number of points where f is not differentiable, then the ordered pair (m, n) is

(A)  (3, 3)

(B)  (2, 4)

(C)  (2, 3)

(D)  (3, 4)

Answer: (C)

6. The value of the integral  is equal to

(A)  2π

(B)  0

(C)  π

(D)  π/2

Answer: (C)

7. is equal to

Answer: (A)

8. A particle is moving in the xy-plane along a curve C passing through the point (3, 3). The tangent to the curve C at the point P meets the x-axis at Q. If the y-axis bisects the segment PQ, then C is a parabola with

(A)  Length of latus rectum 3

(B)  Length of latus rectum 6

(C)  Focus (4/3, 0)

(D)  Focus (0, 3/4)

Answer: (A)

9. Let the maximum area of the triangle that can be inscribed in the ellipse  having one of its vertices at one end of the major axis of the ellipse and one of its sides parallel to the y-axis, be 6√3. Then the eccentricity of the ellipse is

(A)  √3/2

(B)  1/2

(C)  1/√2

(D)  √3/4

Answer: (A)

10. Let the area of the triangle with vertices A(1, α), B(α, 0) and C(0, α) be 4 sq. units. If the points (α, –α), (–α, α) and (α2, β) are collinear, then β is equal to

(A)  64

(B)  −8

(C)  −64

(D)  512

Answer: (C)

11. The number of distinct real roots of the equation x7 – 7x – 2 = 0 is

(A)  5

(B)  7

(C)  1

(D)  3

Answer: (D)

12. A random variable X has the following probability distribution :

The value of P(1 < X < 4 | x ≤ 2) is equal to

(A)  4/7

(B)  2/3

(C)  3/7

(D)  4/5

Answer: (A)

13. The number of solutions of the equation  x ∈ [−3π, 3π] is :

(A)  8

(B)  5

(C)  6

(D)  7

Answer: (D)

14. If the shortest distance between the lines  and  is 1/√3, then the sum of all possible values of λ is :

(A)  16

(B)  6

(C)  12

(D)  15

Answer: (A)

15. Let the points on the plane P be equidistant from the points (–4, 2, 1) and (2, –2, 3). Then the acute angle between the plane P and the plane 2x + y + 3z = 1 is

(A)  π/6

(B)  π/4

(C)  π/3

(D)  5π/12

Answer: (C)

16. Let  be two unit vectors such that  If θ∈ (0, π) is the angle between  then among the statements:

(S2): The projection of 

(A) Only (S1) is true

(B) Only (S2) is true

(C) Both (S1) and (S2) are true

(D) Both (S1) and (S2) are false

Answer: (C)

17. If y = tan1(secx3 – tan x3).  then

(A)  xy′′ + 2y′ = 0

(B) 

(C)  x2y″ – 6y + 3π = 0

(D)  xy″ – 4y′ = 0

Answer: (B)

18. Consider the following statements:

A : Rishi is a judge.

B : Rishi is honest.

C : Rishi is not arrogant.

The negation of the statement “if Rishi is a judge and he is not arrogant, then he is honest” is

(A) B → (A ∨ C)

(B) (~ B) ∧ (A ∧ C)

(C) B → ((~ A) ∨ (~ C))

(D) B → (A ∧ C)

Answer: (B)

19. The slope of normal at any point (x, y), x > 0, y > 0 on the curve y = y(x) is given by  If the curve passes through the point (1, 1), then e·y(e) is equal to

(A)  

(B)  tan(1)

(C)  1

(D) 

Answer: (D)

20. Let λ* be the largest value of λ for which the function fλ(x) = 4λx3 – 36λx2 + 36x + 48 is increasing for all x ∈ ℝ. Then fλ* (1) + fλ* (– 1) is equal to :

(A)  36

(B)  48

(C)  64

(D)  72

Answer: (D)

SECTION-B

21. Let S = {z ∈ℂ : |z – 3| ≤ 1 and  If α + iβ is the point in S which is closest to 4i, then 25(α + β) is equal to ______.

Answer: (80)

22. Let  and let Tn = {A ∈S : An(n+1) = I}. Then the number of elements in  is _______.

Answer: (100)

23. The number of 7-digit numbers which are multiples of 11 and are formed using all the digits 1, 2, 3, 4, 5, 7 and 9 is _____________.

Answer: (576)

24. The sum of all the elements of the set {α ∈ {1, 2, …, 100} : HCF(α, 24) = 1} is ____.

Answer: (1633)

25. The remainder on dividing 1 + 3 + 32 + 33 + … + 32021 by 50 ___________ is

Answer: (4)

26. The area (in sq. units) of the region enclosed between the parabola y2 = 2x and the line x + y = 4 is ___________.

Answer: (18)

27. Let a circle C : (x – h)2 + (y – k)2 = r2, k > 0, touch the x-axis at (1, 0). If the line x + y = 0 intersects the circle C at P and Q such that the length of the chord PQ is 2, then the value of h + k + r is equal to _________.

Answer: (18)

28. In an examination, there are 10 true-false type questions. Out of 10, a student can guess the answer of 4 questions correctly with probability 3/4and the remaining 6 questions correctly with probability 1/4. If the probability that the student guesses the answers of exactly 8 questions correctly out of 10 is 27k/410, then k is equal to _________.

Answer: (479)

29. Let the hyperbola  and the ellipse E : 3x2 + 4y2 = 12 be such that the length of latus rectum of H is equal to the length of latus rectum of E. If eH and eE are the eccentricities of H and E respectively, then the value of 12(eH2 + eE2) is equal to ___________.

Answer: (42)

30. Let P1 be a parabola with vertex (3, 2) and focus (4, 4) and P2 be its mirror image with respect to the line x + 2y = 6. Then the directrix of P2 is x + 2y = _________.

Answer: (10)

JEE Main Session 1 29th July 2022 Shift 1 Question Paper and Answer Key

JEE Main Session 1 29th July 2022 Shift 1

PHYSICS

Section-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii)   Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. Given below are two statements: One is labelled as Assertion (A) and other is labelled as Reason (R).

Assertion (A): Time period of oscillation of a liquid drop depends on surf ace tension (S), if density of the liquid is ρ and radius of the drop is r, then  is dimensionally correct, where K is dimensionless.

Reason (R):Using dimensional analysis we get R.H.S. having different dimension than that of time period.

In the light of above statements, choose the correct answer from the options given below.

(A) Both (A) and (R) are true and (R) is the correct explanation of (A)

(B) Both (A) and (R) are true but (R) is not the correct explanation of (A)

(C) (A) is true but (R) is false

(D) (A) is false but (R) is true

Answer: ()

2. A ball is thrown up vertically with a certain velocity so that, it reaches a maximum height h. Find the ratio of the times in which it is at height h/3 while going up and coming down respectively.

Answer: (B)

3. If  is:

(A) 4

(B) Zero

(C) 8

(D) 16

Answer: (B)

4. A smooth circular groove has a smooth vertical wall as shown in figure. A block of mass m moves against the wall with a speed v. Which of the following curve represents the correct relation between the normal reaction on the block by the wall (N) and speed of the block (v)?

Answer: (A)

5. A ball is projected with kinetic energy E, at an angle of 60° to the horizontal. The kinetic energy of this hall at the highest point of its flight will become

(A) Zero

(B) E/2

(C) E/4

(D) E

Answer: (C)

6. Two bodies of mass 1 kg and 3 kg have position vectors  The magnitude of position vector of centre of mass of this system will be similar to the magnitude of vector :

Answer: (A)

7. Given below are two statements: One is labelled as Assertion (A) and the other· is labelled as Reason (R).

Assertion (A): Clothes containing oil or grease stains cannot be cleaned by water wash.

Reason (R): Because the angle of contact between the oil/ grease and water is obtuse.

In the light of the above statements, choose the correct answer from the option given below.

(A) Both (A) and (R) are true and (R) is the correct explanation of (A)

(B) Both (A) and (R) are true but (R) is not the correct explanation of (A)

(C) (A) is true but (R) is false

(D) (A) is false but (R) is true

Answer: (A)

8. If the length of a wire is made double and radius is halved of its respective values. Then, the Young’s modulus of the material of the wire will :

(A) Remain same

(B) Become 8 times its initial value

(C) Become 1/4th of its initial value

(D) Become 4 times its initial value

Answer: (A)

9. The time period of oscillation of a simple pendulum of length L suspended from the roof of a vehicle, which moves without friction down an inclined plane of inclination α, is given by:

Answer: (A)

10. A spherically symmetric charge distribution is considered with charge density varying as

Where, r(r < R) is the distance from the centre O (as shown in figure) The electric field at point P will be :

Answer: (C)

11. Given below are two statements.

Statement I: Electric potential is constant within and at the surface of each conductor.

Statement II: Electric field just outside a charged conductor is perpendicular to the surface of the conductor at every point.

In the light of the above statements, choose the most appropriate answer from the options given below.

(A) Both statement I and statement II are correct

(B) Both statement I and statement II are incorrect

(C) Statement I is correct but statement II is incorrect

(D) Statement I is incorrect but statement II is correct

Answer: (A)

12. Two metallic wires of identical dimensions are connected in series. If σ1 and σ2 are the conductivities of these wires, respectively, the effective conductivity of the combination is :

Answer: (B)

13. An alternating emf E = 440 sin100πt is applied to a circuit containing an inductance of  If an a.c. ammeter is connected in the circuit, its reading will be:

(A) 4.4 A

(B) 1.55 A

(C) 2.2 A

(D) 3.11 A

Answer: (C)

14. A coil of inductance 1 H and resistance 100 Ω is connected to a battery of 6 V. Determine approximately :

(a) The time elapsed before the current acquires half of its steady – state value.

(b) The energy stored in the magnetic field associated with the coil at an instant 15 ms after the circuit is switched on.

(Given ln2 = 0.693, e–3/2 = 0.25)

(A) t = 10 ms; U = 2 mJ

(B) t = 10 ms; U = 1 mJ

(C) t = 7 ms; U = 1 mJ

(D) t = 7 ms; U = 2 mJ

Answer: (C)

15. Match List-I with List-II:

Choose the correct answer from the options given below :

(A) (a)-(iii), (b)-(ii), (c)-(i), (d)-(iv)

(B) (a)-(ii), (b)-(i), (c)-(iii), (d)-(iv)

(C) (a)-(ii), (b)-(iv), (c)-(iii), (d)-(i)

(D) (a)-(iii), (b)-(i), (c)-(ii), (d)-(iv)

Answer: (B)

16. The kinetic energy of emitted electron is E when the light incident on the metal has wavelength λ. To double the kinetic energy, the incident light must have wavelength:

Answer: (B)

17. Find the ratio of energies of photons produced due to transition of an electron of hydrogen atom from its (i) second permitted energy level to the first level, and (ii) the highest permitted energy level to the first permitted level.

(A) 3 : 4

(B) 4 : 3

(C) 1 : 4

(D) 4 : 1

Answer: (A)

18. Find the modulation index of an AM wave having 8 V variation where maximum amplitude of the AM wave is 9 V.

(A) 0.8

(B) 0.5

(C) 0.2

(D) 0.1

Answer: (A)

19. A travelling microscope has 20 divisions per cm on the main scale while its vernier scale has total 50 divisions and 25 vernier scale divisions are equal to 24 main scale divisions, what is the least count of the travelling microscope?

(A) 0.001 cm

(B) 0.002 mm

(C) 0.002 cm

(D) 0.005 cm

Answer: (C)

20. In an experiment to find out the diameter of the wire using a screw gauge, the following observations were noted :

(A) Screw moves 0.5 mm on main scale in one complete rotation

(B) Total divisions on circular scale = 50

(C) Main scale reading is 2.5 mm

(D) 45th division of circular scale is in the pitch line

(E) Instrument has 0.03 mm negative error

Then the diameter of wire is :

(A) 2.92 mm

(B) 2.54mm

(C) 2.98mm

(D) 3.45mm

Answer: (C)

SECTION-B

21. An object is projected in the air with initial velocity u at an angle θ. The projectile motion is such that the horizontal range R, is maximum. Another object is projected in the air with a horizontal range half of the range of first object. The initial velocity remains same in both the case. The value of the angle of projection, at which the second object is projected, will be ______ degree.

Answer: (15)

22. If the acceleration due to gravity experienced by a point mass at a height h above the surface of earth is same as that of the acceleration due to gravity at a depth αh(h << Re) from the earth surface. The value of α will be ________.

(Use Re = 6400 km)

Answer: (2)

23. The pressure P1 and density d1 of diatomic gas (γ = 7/5) changes suddenly to P2 (>P1) and d2 respectively during an adiabatic process. The temperature of the gas increases and becomes _____ times of its initial temperature.

(Given d2/d1 =32)

Answer: (4)

24. One mole of a monoatomic gas is mixed with three moles of a diatomic gas. The molecular specific heat of mixture at constant volume is  then the value of α will be _______. (Assume that the given diatomic gas has no vibrational mode).

Answer: (3)

25. The current I flowing through the given circuit will be ________A.

Answer: (2)

26. A closely wounded circular coil of radius 5 cm produces a magnetic field of 37.68 × 10–4 T at its center. The current through the coil is _______ A.

[Given, number of turns in the coil is 100 and π =3.14]

Answer: (3)

27. Two light beams of intensities 4I and 9I interfere on a screen. The phase difference between these beams on the screen at point A is zero and at point B is π. The difference of resultant intensities, at the point A and B, will be _______I.

Answer: (24)

28. A wire of length 314 cm carrying current of 14 A is bent to form a circle. The magnetic moment of the coil is _______ A–m2. [Given π =3.14]

Answer: (11)

29. The X–Y plane be taken as the boundary between two transparent media M1 and M2. M1 in Z ≥ 0 has a refractive index of √2 and M2 with Z < 0 has a refractive index of √3. A ray of light travelling in M1 along the direction given by the vector  is incident on the plane of separation. The value of difference between the angle of incident in M1 and the angle of refraction in M2 will be ______ degree.

Answer: (15)

30. If the potential barrier across a p–n junction is 0.6 V. Then the electric field intensity, in the depletion region having the width of 6 × 10–6 m, will be ______× 105 N/C.

Answer: (1)

CHEMISTRY

SECTION-A

1. Which of the following pair of molecules contain odd electron molecule and an expanded octet molecule?

(A) BCl3 and SF6

(B) NO and H2SO4

(C) SF6 and H2SO4

(D) BCl3 and NO

Answer: (B)

2. 

Consider the above reaction, the limiting reagent of the reaction and number of moles of NH3 formed respectively are:

(A) H2, 1.42 moles 

(B) H2, 0.71 moles   

(C) N2, 1.42 moles

(D) N2, 0.71 moles

Answer: (C)

3. 100 mL of 5% (w/v) solution of NaCl in water was prepared in 250 mL beaker. Albumin from the egg was poured into NaCl solution and stirred well. This resulted in a/ an :

(A) Lyophilic sol 

(B) Lyophobic sol   

(C) Emulsion

(D) Precipitate

Answer: (A)

4. The first ionization enthalpy of Na, Mg and Si, respectively, are: 496, 737 and 786 kJ mo11. The first ionization enthalpy (kJ mol1) of Al is:

(A) 487

(B) 768

(C) 577

(D) 856

Answer: (C)

5. In metallurgy the term “gangue” is used for:

(A)  Contamination of undesired earthy materials.

(B)  Contamination of metals, other than desired     metal

(C)  Minerals which are naturally occurring in pure form

(D)  Magnetic impurities in an ore.

Answer: (A)

6. The reaction of zinc with excess of aqueous alkali, evolves hydrogen gas and gives :

(A) Zn(OH)2

(B) ZnO

(C) [Zn(OH)4]2

(D) [ZnO2]2

Answer: (D)

7. Lithium nitrate and sodium nitrate, when heated separately, respectively, give :

(A) LiNO2 and NaNO2

(B)  Li2O and Na2O  

(C) Li2O and NaNO2

(D) LiNO2 and Na2O

Answer: (C)

8. Number of lone pairs of electrons in the central atom of SCl2, O3, ClF3 and SF6, respectively, are :

(A) 0, 1, 2 and 2   

(B) 2, 1, 2 and 0    

(C) 1, 2, 2 and 0  

(D) 2, 1, 2 and 0

Answer: (B)

9. In following pairs, the one in which both transition metal ions are colourless is :

(A) Sc3+, Zn2+

(B) Ti4+, Cu2+

(C) V2+, Ti3+

(D) Zn2+, Mn2+

Answer: (A)

10. In neutral or faintly alkaline medium, KMnO4 being a powerful oxidant can oxidize, thiosulphate almost quantitatively, to sulphate. In this reaction overall change in oxidation state of manganese will be :

(A) 5

(B) 1

(C) 0

(D) 3

Answer: (D)

11. Which among the following pairs has only herbicides ?

(A) Aldrin and Dieldrin

(B) Sodium chlorate and Aldrin

(C) Sodium arsinate and Dieldrin

(D) Sodium chlorate and sodium arsinite.

Answer: (D)

12. Which among the following is the strongest Bronsted base ?

Answer: (D)

13. Which among the following pairs of the structures will give different products on ozonolysis? (Consider the double bonds in the structures are rigid and not delocalized.)

Answer: (C)

14. 

Considering the above reactions, the compound ‘A’ and compound ‘B’ respectively are :

Answer: (C)

15. 

Consider the above reaction sequence, the Product ‘C’ is :

Answer: (D)

16. 

Consider the above reaction, the compound ‘A’ is :

Answer: (C)

17. 

Which among the following represent reagent ‘A’?

Answer: (A)

18. Consider the following reaction sequence :

Answer: (B)

19. Which of the following compounds is an example of hypnotic drug ?

(A) Seldane

(B) Amytal

(C) Aspartame

(D) Prontosil

Answer: (B)

20. A compound ‘X’ is acidic and it is soluble in NaOH solution, but insoluble in NaHCO3 Compound ‘X’ also gives violet colour with neutral FeCI3 solution. The compound ‘X’ is :

Answer: (B)

SECTION-B

21. Resistance of a conductivity cell (cell constant 129 ml) filled with 74.5 ppm solution of KCl is 100Ω (labelled as solution 1). When the same cell is filled with KCl solution of 149 ppm, the resistance is 50Ω (labelled as solution 2). The ratio of molar conductivity of solution 1 and solution 2 is i.e.  The value of x is ______. (Nearest integer)

Given, molar mass of KCl is 74.5 g moll

Answer: (1000)

22. Ionic radii of cation A+ and anion B are 102 and 181 pm respectively. These ions are allowed to crystallize into an ionic solid. This crystal has cubic close packing for B. A+ is present in all octahedral voids. The edge length of the unit cell  of  the  crystal AB is _____ pm. (Nearest  Integer)

Answer: (512)

23. The minimum uncertainty in the speed of an electron in an one dimensional region of length 2aO (Where a0 = Bohr radius 52.9 pm) is _____km s1.   (Given : Mass of electron = 9.l × 1031 kg, Planck’s constant h = 6.63 × 1034Js)

Answer: (548)

24. When 600 mL of 0.2 M HNO3 is mixed with 400 mL of 0.1M NaOH solution in a flask, the rise in temperature of the flask is _______ × 102° (Enthalpy of neutralisation = 57 kJ mo11 and Specific heat of water = 4.2 JK1 g1

(Neglect heat capacity of flask)

Answer: (54)

25. If O2 gas is bubbled through water at 303 K, the number of millimoles of O2 gas that dissolve in 1 litre of water is_______. (Nearest Integer)

(Given : Henry’s Law constant for O2 at 303 K is 46.82 k bar and partial pressure of O2 = 0.920 bar) 

(Assume solubility of O2 in water is too small, nearly negligible)

Answer: (1)

26. If the solubility product of PbS is 8 × 1028, then the solubility of PbS in pure water at 298 K is x × 10l6mol L1.  The value of x is ________. (Nearest Integer)

[Given √2 = 1.41]

Answer: (282)

27. The reaction between X and Y is first order with respect to X and zero order with respect to Y.

Examine the data of table and calculate ratio of numerical values of M and L. (Nearest Integer)

Answer: (40)

28. In a linear tetrapeptide (Constituted with different amino acids), (number  of  amino acids) – (number of peptide bonds) is______.

Answer: (1)

29. In bromination of Propyne, with Bromine 1, 1, 2, 2-tetrabromopropane is obtained in 27% yield. The amount of 1, 1, 2, 2 tetrabromopropane obtained from 1 g of Bromine in this reaction is ______ × 101 (Nearest integer) 

(Molar Mass : Bromine = 80 g/mol)

Answer: (3)

30. [Fe(CN)6]3 should be an inner orbital complex. Ignoring the pairing energy, the value of crystal field stabilization energy for this complex is (–) _________ ∆o. (Nearest integer)

Answer: (2)

MATHEMATICS

SECTION-A

1. Let R be a relation from the set {1, 2, 3, ….., 60} to itself such that R = {(a, b) : b = pq, where p, q ≥ 3 are prime numbers}. Then, the number of elements in R is :

(A) 600

(B) 660

(C) 540

(D) 720

Answer: (B)

2. If z = 2 + 3i, then  is equal to :

(A) 244

(B) 224

(C) 245

(D) 265

Answer: (A)

3. Let A and B be two 3 × 3 non-zero real matrices such that AB is a zero matrix. Then

(A) the system of linear equations AX = 0 has a unique solution

(B) the system of linear equations AX = 0 has infinitely many solutions

(C) B is an invertible matrix

(D) adj(A) is an invertible matrix

Answer: (B)

4. If  then the maximum value of a is:

(A) 198

(B) 202

(C) 212

(D) 218

Answer: (C)

5. If  where α, β, γ ∈ R, then which of the following is NOT correct?

(A) α2 + β2 + γ2 = 6

(B) αβ + βγ + γα + 1 = 0

(C) αβ2 + βγ2 + γα2 + 3 = 0

(D) α2 – β2 + γ2 = 4

Answer: (C)

6. The integral  is equal to

(A) tan1 (2)

(B) 

(C) 

(D) 1/2

Answer: (B)

7. Let the solution curve y = y(x) of the differential equation  pass through the point (0, π/2). Then,  is equal to

(A) π/4

(B) 3π/4

(C) π/2

(D) 3π/2

Answer: (B)

8. Let a line L pass through the point intersection of the lines bx + 10y – 8 = 0 and  If the line L also passes through the point (1, 1) and touches the circle 17(x2 + y2) = 16, then the eccentricity of the ellipse .

Answer: (B)

9. If the foot of the perpendicular from the point A(–1, 4, 3) on the plane P : 2x + my + nz = 4, is (-2, 7/2, 3/2), then the distance of the point A from the plane P, measured parallel to a line with direction ratios 3, –1, –4, is equal to

(A) 1

(B) √26

(C) 2√2

(D) √14

Answer: (B)

10. Let  Let  be a vector satisfying  If  are non-parallel, then the value of λ is

(A) –5

(B) 5

(C) 1

(D) –1

Answer: (A)

11. The angle of elevation of the top of a tower from a point A due north of it is α and from a point B at a distance of 9 units due west of A is  If the distance of the point B from the tower is 15 units, then cot α is equal to :

(A) 6/5

(B) 9/5

(C) 4/3

(D) 7/3

Answer: (A)

12. The statement (p ∧ q) ⇒ (p ∧ r) is equivalent to :

(A) q ⇒ (p ∧ r)

(B) p ⇒ (p ∧ r)

(C) (p ∧ r) ⇒ (p ∧ q)

(D) (p ∧ q) ⇒ r

Answer: (D)

13. Let the circumcentre of a triangle with vertices A(a, 3), B(b, 5) and C(a, b), ab > 0 be P(1, 1). If the line AP intersects the line BC at the point Q(k1, k2), then k1 + k2 is equal to :

(A) 2

(B) 4/7

(C) 2/7

(D) 4

Answer: (B)

14. Let  be two unit vectors such that the angle between them is π/4. If θ is the angle between the vectors  then the value of 164 cos2θ is equal to :

(A) 90 + 27√2

(B) 45 + 18√2

(C) 90 + 3√2

(D) 54 + 90√2

Answer: (A)

15. If  then f(e3) + f(e–3) is equal to :

(A) 9

(B) 9/2

(C) 

(D) 

Answer: (D)

16. The area of the region  is equal to

Answer: (D)

17. Let the focal chord of the parabola P :y2 = 4x along the line L : y = mx + c, m > 0 meet the parabola at the points M and N. Let the line L be a tangent to the hyperbola H : x2 – y2 = 4. If O is the vertex of P and F is the focus of H on the positive x-axis, then the area of the quadrilateral OMFN is

(A) 2√6

(B) 2√14

(C) 4√6

(D) 4√14

Answer: (B)

18. The number of points, where the function f: ℝ → ℝ, f(x) = |x – 1|cos|x – 2|sin|x – 1| + (x – 3)|x2 – 5x + 4|, is NOT differentiable, is

(A) 1

(B) 2

(C) 3

(D) 4

Answer: (B)

19. Let S = {1, 2, 3, …, 2022}. Then the probability that a randomly chosen number n from the set S such that HCF (n, 2022) = 1, is

Answer: (D)

20. Let  Then which of the following statements are true?

P :x = 0 is a point of local minima of f

Q: x = √2 is a point of inflection of f

R : fʹ is increasing for x > √2

(A) Only P and Q

(B) Only P and R

(C) Only Q and R

(D) All P, Q and R

Answer: (D)

SECTION-B

21. Let S = {θ ∈ (0, 2π) : 7 cos2θ – 3 sin2θ – 2 cos22θ = 2}. Then, the sum of roots of all the equations x2 – 2 (tan2θ + cot2θ) x + 6 sin2θ = 0, θ ∈ S, is _______.

Answer: (16)

22. Let the mean and the variance of 20 observations x1, x2, …., x20 be 15 and 9, respectively. For a ∈ R, if the mean of (x1 + α)2, (x2 + α)2, …., (x20 + α)2 is 178, then the square of the maximum value of α is equal to ___________.

Answer: (4)

23. Let a line with direction ratios a, – 4a, –7 be perpendicular to the lines with direction ratios 3, – 1, 2b and b, a, – 2. If the point of intersection of the line  and the plane x – y + z = 0 is (α, β, γ), then α + β + γ is equal to ______.

Answer: (10)

24. Let a1, a2, a3, …. be an A.P. If  then 4a2 is equal to ________.

Answer: (16)

25. Let the ratio of the fifth term from the beginning to the fifth term from the end in the binomial expansion of  in the increasing powers of  If the sixth term from the beginning is  then α is equal to ___________.

Answer: (84)

26. The number of matrices of order 3 × 3, whose entries are either 0 or 1 and the sum of all the entries is a prime number, is _________.

Answer: (282)

27. Let p and p + 2 be prime numbers and let 

Then the sum of the maximum values of α and β, such that pα and (p + 2)β divide Δ, is _______.

Answer: (4)

28. If  then 34 k is equal to ________.

Answer: (286)

29. Let S = {4, 6, 9} and T = {9, 10, 11, …,1000}. If A = {a1 + a2 + … +ak :k∈N, a1, a2, a3, …, ak∈S}, then the sum of all the elements in the set T – A is equal to ________.

Answer: (11)

30. Let the mirror image of a circle c1 : x2 + y2 – 2x – 6y + α = 0 in line y = x + 1 be c2 : 5x2 + 5y2 + 10gx + 10fy + 38 = 0. If r is the radius of circle c2, then α + 6r2 is equal to _________.

Answer: (12)

JEE Main Session 1 28th July 2022 Shift 1 Question Paper and Answer Key

JEE Main Session 1 28th July 2022 Shift 1

PHYSICS

Section-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii)   Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. The dimensions of (B20) will be:

(ifμ0 : permeability of free space and B : magnetic field)

(A) [ML2T2]

(B) [MLT2]

(C) [ML1T2]

(D) [ML2T2A1]

Answer: (C)

2. A NCC parade is going at a uniform speed of 9 km/h under a mango tree on which a monkey is sitting at a height of 19.6 m. At any particular instant, the monkey drops a mango. A cadet will receive the mango whose distance from the tree at time of drop is :

(Given g = 9.8 m/s2)

(A) 5 m

(B) 10 m

(C) 19.8 m

(D) 24.5 m

Answer: (A)

3. In two different experiments, an object of mass   5 kg moving with a speed of 25 ms–1 hits two different walls and comes to rest within   (i) 3 second, (ii) 5 seconds, respectively.

Choose the correct option out of the following :

(A) Impulse and average force acting on the object  will be same for both the cases.

(B) Impulse will be same for both the cases but the  average force will be different.

(C) Average force will be same for both the cases    but the impulse will be different.

(D) Average force and impulse will be different for  both the cases.

Answer: (B)

4. A balloon has mass of 10 g in air. The air escapes from the balloon at a uniform rate with velocity 5 cm/s. If the balloon shrinks in 5 s completely. Then, the average force acting on that balloon will be (in dyne).

(A) 3

(B) 9

(C) 12

(D) 18

Answer: (B)

5. If the radius of earth shrinks by 2% while its mass remains same. The acceleration due to gravity on the earth’s surface will approximately :

(A) decrease by 2%

(B) decrease by 4%

(C) increase by 2%

(D) increase by 4%

Answer: (D)

6. The force required to stretch a wire of cross-section 1 cm2 to double its length will be: (Given Yong’s modulus of the wire = 2 × 1011 N/m2)

(A) 1 × 107 N

(B) 1.5 × 107 N

(C) 2 × 107 N

(D) 2.5× 107 N

Answer: (C)

7. A Carnot engine has efficiency of 50%. If the temperature of sink is reduced by 40°C, its efficiency increases by 30%. The temperature of the source will be :

(A) 166.7 K

(B) 255.1 K

(C) 266.7 K

(D) 367.7 K

Answer: (C)

8. Given below are two statements :

Statement I: The average momentum of a molecule in a sample of an ideal gas depends on temperature.

Statement II: The rms speed of oxygen molecules in a gas is v. If the temperature is doubled and the oxygen molecules dissociate into oxygen atoms, the rms speed will become 2v.

In the light of the above statements, choose the correct answer from the options given below :

(A) Both Statement I and Statement II are true

(B) Both Statement I and Statement II are false

(C) Statement I is true but Statement II is false

(D) Statement I is false but Statement II is true

Answer: (D)

9. In the wave equation  the velocity of the wave will be :

(A) 200 m/s

(B) 200√2 m/s

(C) 400 m/s

(D) 400√2 m/s

Answer: (C)

10. Two capacitors, each having capacitance 40μF are connected in series. The space between one of the capacitors is filled with dielectric material of dielectric constant K such that the equivalence capacitance of the system became 24μ The value of K will be :

(A) 1.5

(B) 2.5

(C) 1.2

(D) 3

Answer: (A)

11. A wire of resistance R1 is drawn out so that its length is increased by twice of its original length. The ratio of new resistance to original resistance is:

(A) 9 : 1

(B) 1 : 9

(C) 4 : 1

(D) 3 : 1

Answer: (A)

12. The current sensitivity of a galvanometer can be increased by :

(A) decreasing the number of turns

(B) increasing the magnetic field

(C) decreasing the area of the coil

(D) decreasing the torsional constant of the spring

Choose the most appropriate answer from the options given below :

(A) (B) and (C) only

(B) (C) and (D) only

(C) (A) and (C) only

(D) (B) and (D) only

Answer: (D)

13. As shown in the figure, a metallic rod of linear density 0.45 kg m–1 is lying horizontally on a smooth incline plane which makes an angle of 45° with the horizontal. The minimum current flowing in the rod required to keep it stationary, when 0.15 T magnetic field is acting on it in the vertical upward direction, will be :

{Use g = 10 m/s2}

(A) 30 A

(B) 15 A

(C) 10 A

(D) 3 A

Answer: (A)

14. The equation of current in a purely inductive circuit is 5sin(49πt – 30°). If the inductance is 30mH then the equation for the voltage across the inductor, will be :

{Let π = 22/7}

(A) 1.47sin(49πt – 30°)

(B) 1.47sin(49πt + 60°)

(C) 23.1sin(49πt – 30°)

(D) 23.1sin(49πt + 60°)

Answer: (D)

15. As shown in the figure, after passing through the medium 1. The speed of light v2 in medium 2 will be :

(Given c = 3 × 108 ms–1)

(A) 1.0 × 108 ms–1

(B) 0.5 × 108 ms–1

(C) 1.5 × 108 ms–1

(D) 3.0 × 108 ms–1

Answer: (A)

16. In normal adjustment, for a refracting telescope, the distance between objective and eye piece is 30 cm. The focal length of the objective, when the angular magnification of the telescope is 2, will be:

(A) 20 cm

(B) 30cm

(C) 10cm

(D) 15cm

Answer: (A)

17. The equation  can be used to find the de-Brogli wavelength of an electron. In this equation x stands for :

Where,   m = mass of electron

P = momentum of electron

K = Kinetic energy of electron

V = Accelerating potential in volts for electron

(A) √mK

(B) √P

(C) √K

(D) √V

Answer: (D)

18. The half life period of a radioactive substance is 60 days. The time taken for 7/8th of its original mass to disintegrate will be :

(A) 120 days

(B) 130 days

(C) 180 days

(D) 20 days

Answer: (C)

19. Identify the solar cell characteristics from the following options :

Answer: (B)

20. In the case of amplitude modulation to avoid distortion the modulation index (μ)should be :

(A) μ≤ 1

(B) μ≥ 1

(C) μ = 2

(D) μ = 0

Answer: (A)

SECTION-B

21. If the projection of  is zero. Then, the value of α will be

Answer: (5)

22. A freshly prepared radioactive source of half life 2 hours 30 minutes emits radiation which is 64 times the permissible safe level. The minimum time, after which it would be possible to work safely with source, will be ________ hours.

Answer: (15)

23. In a Young’s double slit experiment, a laser light of 560 nm produces an interference pattern with consecutive bright fringes’ separation of 7.2 mm. Now another light is used to produce an interference pattern with consecutive bright fringes’ separation of 8.1 mm. The wavelength of second light is _________ nm.

Answer: (630)

24. The frequencies at which the current amplitude in an LCR series circuit becomes 1/√2 times its maximum value, are 212 rad s–1 and 232 rad s–1. The value of resistance in the circuit is R = 5ΩTheself inductance in the circuit is ________ mH.

Answer: (250)

25. As shown in the figure, a potentiometer wire of resistance 20Ω and length 300 cm is connected with resistance box (R.B.) and a standard cell of emf 4 V. For a resistance ‘R’ of resistance box introduced into the circuit, the null point for a cell of 20 mV is found to be 60 cm. The value of ‘R’ is __________Ω.

Answer: (780)

26. Two electric dipoles of dipole moments 2 × 10–30 cm and 2.4 × 10–30 cm are placed in two difference uniform electric fields of strengths  5 × 104 NC–1 and 15 × 104 NC–1 respectively. The ratio of maximum torque experienced by the electric dipoles will be 1/x. The value of x is _______.

Answer: (6)

27. The frequency of echo will be _________ Hz if the train blowing a whistle of frequency 320 Hz is moving with a velocity of 36 km/h towards a hill from which an echo is heard by the train driver. Velocity of sound in air is 330 m/s.

Answer: (340)

28. The diameter of an air bubble which was initially 2 mm, rises steadily through a solution of density 1750 kg m–3 at the rate of 0.35 cms–1. The coefficient of viscosity of the solution is _______ poise (in nearest integer). (the density of air is negligible).

Answer: (11)

29. A block of mass ‘m’ (as shown in figure) moving with kinetic energy E compresses a spring through a distance 25 cm when, its speed is halved. The value of spring constant of used spring will be nE Nm–1 for n = ___________.

Answer: (24)

30. Four identical discs each of mass ‘M’ and diameter ‘a’ are arranged in a small plane as shown in figure. If the moment of inertia of the system about OO’ is  Then, the value of x will be _________.

Answer: (3)

CHEMISTRY

SECTION-A

1. Identify the incorrect statement from the following.

(A) A circular path around the nucleus in which an electron moves is proposed as Bohr’s orbit.

(B) An orbital is the one electron wave function (Ψ) in an atom.

(C) The existence of Bohr’s orbits is supported by hydrogen spectrum.

(D) Atomic orbital is characterised by the quantum numbers n and l only

Answer: (D)

2. Which of the following relation is not correct ?

(A) ∆H = ∆U − P∆V

(B) ∆U = q + W

(C) ∆Ssys + ∆Ssurr≥ 0

(D) ∆G = ∆H − T∆S

Answer: (A)

3. Match List-I with List-II.

Choose the correct answer from the options given below :

(A) (A) – (I), (B) – (II), (C) – (III), (D) – (IV)

(B) (A) – (IV), (B) – (I), (C) – (II), (D) – (III)

(C) (A) – (II), (B) – (I), (C) – (IV), (D) – (III)

(D) (A) – (II), (B) – (I), (C) – (III), (D) – (IV)

Answer: (C)

4. Match List-I with List-II.

Choose the correct answer from the options given below :

(A) (A) – (II), (B) – (III), (C) – (I), (D) – (IV)

(B) (A) – (III), (B) – (II), (C) – (I), (D) – (IV)

(C) (A) – (III), (B) – (IV), (C) – (II), (D) – (I)

(D) (A) – (III), (B) – (II), (C) – (IV), (D) – (I)

Answer: (C)

5. In which of the following pairs, electron gain enthalpies of constituent elements are nearly the same or identical ?

(A) Rb and Cs      (B) Na and K

(C) Ar and Kr      (D) I and At

Choose the correct answer from the options given below :

(A) (A) and (B) only

(B) (B) and (C) only

(C) (A) and (C) only

(D) (C) and (D) only

Answer: (C)

6. Which of the reaction is suitable for concentrating ore by leaching process ?

(A) 2Cu2S + 3O2→ 2Cu2O + 2SO2

(B) Fe3O4 + CO → 3FeO + CO2

(C) Al2O3 + 2NaOH + 3H2O →2Na[Al(OH)4]

(D) Al2O3 + 6Mg → 6MgO + 4Al

Answer: (C)

7. The metal salts formed during softening of hardwater using Clark’s method are :

(A) Ca(OH)2 and Mg(OH)2

(B) CaCO3 and Mg(OH)2

(C) Ca(OH)2 and MgCO3

(D) CaCO3 and MgCO3

Answer: (B)

8. Which of the following statement is incorrect ?

(A) Low solubility of LiF in water is due to its small hydration enthalpy.

(B) KO2 is paramagnetic.

(C) Solution of sodium in liquid ammonia is conducting in nature.

(D) Sodium metal has higher density than potassium metal

Answer: (A)

9. Match List-I with List-II, match the gas evolved during each reaction.

Choose the correct answer from the options given below :

(A) (A) – (II), (B) – (III), (C) – (I), (D) – (IV)

(B) (A) – (III), (B) – (I), (C) – (IV), (D) – (II)

(C) (A) – (II), (B) – (IV), (C) – (I), (D) – (III)

(D) (A) – (III), (B) – (IV), (C) – (I), (D) – (II)

Answer: (C)

10. Which of the following has least tendency to liberate H2 from mineral acids ?

(A) Cu

(B) Mn

(C) Ni

(D) Zn

Answer: (A)

11. Given below are two statements

Statement I : In polluted water values of both dissolved oxygen and BOD are very low.

Statement II : Eutrophication results in decrease in the amount of dissolved oxygen.

In the light of the above statements, choose the most appropriate answer from the options given below :

(A) Both Statement I and Statement II are true

(B) Both Statement I and Statement II are false

(C) Statement I is true but Statement II is false

(D) Statement I is false but Statement II is true

Answer: (D)

12. Match List-I with List-II.

Choose the correct answer from the options given below :

(A) (A) – (II), (B) – (I), (C) – (IV), (D) – (III)

(B) (A) – (IV), (B) – (III), (C) – (I), (D) – (II)

(C) (A) – (III), (B) – (IV), (C) – (I), (D) – (II)

(D) (A) – (IV), (B) – (III), (C) – (II), (D) – (I)

Answer: (C)

13. Choose the correct option for the following reactions.

(A) ‘A’ and ‘B’ are both Markovnikov addition products.

(B) ‘A’ is Markovnikov product and ‘B’ is antiMarkovnikov product.

(C) ‘A’ and ‘B’ are both anti-Markovnikov products.

(D) ‘B’ is Markovnikov and ‘A’ is antiMarkovnikov product.

Answer: (B)

14. Among the following marked proton of which compound shows lowest pKavalue ?

Answer: (C)

15. Identify the major product A and B for the below given reaction sequence.

Answer: (B)

16. Identify the correct statement for the below given transformation.

Answer: (C)

17. Terylene polymer is obtained by condensation of :

(A) Ethane-1, 2-diol and Benzene-1, 3 dicarboxylicacid

(B) Propane-1, 2-diol and Benzene-1, 4 dicarboxylicacid

(C) Ethane-1, 2-diol and Benzene-1, 4 dicarboxylicacid

(D) Ethane-1, 2-diol and Benzene-1, 2 dicarboxylicacid

Answer: (C)

18. For the below given cyclic hemiacetal (X), the correct pyranose structure is :

Answer: (D)

19. Statements about Enzyme Inhibitor Drugs are given below :

(A) There are Competitive and Non-competitive inhibitor drugs.

(B) These can bind at the active sites and allosteric sites.

(C) Competitive Drugs are allosteric site blocking drugs.

(D) Non-competitive Drugs are active site blocking drugs.

Choose the correct answer from the options given below :

(A) (A), (D) only

(B) (A), (C) only

(C) (A), (B) only

(D) (A), (B), (C) only

Answer: (C)

20. For kinetic study of the reaction of iodide ion with H2O2 at room temperature :

(A) Always use freshly prepared starch solution.

(B) Always keep the concentration of sodium thiosulphate solution less than that of KI solution.

(C) Record the time immediately after the appearance of blue colour.

(D) Record the time immediately before the appearance of blue colour.

(E) Always keep the concentration of sodium thiosulphate solution more than that of KI solution.

Choose the correct answer from the options given below :

(A) (A), (B), (C) only

(B) (A), (D), (E) only

(C) (D), (E) only

(D) (A), (B), (E) only

Answer: (A)

SECTION-B

21. In the given reaction,

X + Y + 3Z ⇆ XYZ3

if one mole of each of X and Y with 0.05 mol of Z gives compound XYZ3. (Given : Atomic masses of X, Y and Z are 10, 20 and 30 amu, respectively). The yield of XYZ3 is __________ g.

(Nearest integer)

Answer: (2)

22. An element M crystallises in a body centred cubic unit cell with a cell edge of 300 pm. The density of the element is 6.0 g cm–3. The number of atoms present in 180 g of the element is ______ × 1023. (Nearest integer)

Answer: (22)

23. The number of paramagnetic species among the following is _________.

B2, Li2, C2, C2, O22, O2+ and He2+

Answer: (4)

24. 150 g of acetic acid was contaminated with 10.2 g ascorbic acid (C6H8O6) to lower down its freezing point by (x × 10–1)°C. The value of x is ________. (Nearest integer) [Given Kf = 3.9 K kg mol–1;  Molar mass of ascorbic acid = 176 g mol–1]

Answer: (15)

25. Ka for butyric acid (C3H7COOH) is 2 × 10–5. The pH of 0.2 M solution of butyric acid is ___ × 10–1. (Nearest integer) [Given log 2 = 0.30]

Answer: (27)

26. For the given first order reaction

A → B

thehalf life of the reaction is 0.3010 min. The ratio of the initial concentration of reactant to the concentration of reactant at time 2.0 min will be equal to ___________. (Nearest integer)

Answer: (100)

27. The number of interhalogens from the following having square pyramidal structure is :

ClF3, IF7, BrF5, BrF3, I2Cl6, IF5, ClF, ClF5

Answer: (3)

28. The disproportionation of MnO42− in acidic medium resulted in the formation of two manganese compounds A and B. If the oxidation state of Mn in B is smaller than that of A, then the spin-only magnetic moment (μ) value of B in BM is ___________. (Nearest integer)

Answer: (4)

29. Total number of relatively more stable isomer(s) possible for octahedral complex [Cu(en)2(SCN)2] will be ___________.

(A)

Answer: (3)

30. On complete combustion of 0.492 g of an organic compound containing C, H and O, 0.7938 g of CO2 and 0.4428 g of H2O was produced. The % composition of oxygen in the compound is _____.

Answer: (46)

MATHEMATICS

SECTION-A

1. Let the solution curve of the differential equation  intersect the line x = 1 at y = 0 and the line x = 2 at y = α. Then the value of α is

(A) 1/2

(B) 3/2

(C) −3/2

(D) 5/2

Answer: (B)

2. Considering only the principal values of the inverse trigonometric functions, the domain of the function  is

(A) (−∞, 1/4]

(B) [−1/4, ∞)

(C) (−1/3, ∞)

(D) (−∞, 1/3]

Answer: (B)

3. Let the vectors   and  t ∈ R be such that for α, β, γ ∈ R,  ⇒ α = β = γ = 0. Then, the set of all values of t is

(A) A non-empty finite set

(B) Equal to N

(C) Equal to R−{0}

(D) Equal to R

Answer: (C)

4. Considering the principal values of the inverse trigonometric functions, the sum of all the solutions of the equation cos−1(x) – 2sin−1(x) = cos−1(2x) is equal to

(A) 0

(B) 1

(C) 1/2

(D) −1/2

Answer: (A)

5. Let the operations *, ⨀ ∈ {∧, ∨}. If (p * q) ⨀ (p ⨀ ~q) is a tautology, then the ordered pair (*, ⨀) is

(A) (∨, ∧)

(B) (∨, ∨)

(C) (∧, ∧)

(D) (∧, ∨)

Answer: (B)

6. Let a vector  be such that for every (x, y) ∈ R × R – {(0, 0)}, the vector  is perpendicular to the vector  Then the value of  is equal to:

(A) 9√3

(B) 27√3

(C) 9

(D) 81

Answer: (B)

7. For t ∈ (0, 2π), if ABC is an equilateral triangle with vertices A(sin t – cos t), B(cos t, sin t) and C(a, b) such that its orthocentre lies on a circle with centre (1, 1/3), then (a2 – b2) is equal to

(A) 8/3

(B) 8

(C) 77/9

(D) 80/9

Answer: (B)

8. For α ∈ N, consider a relation R on N given by R = {(x, y) : 3x + αy is a multiple of 7}. The relation R is an equivalence relation if and only if

(A) α = 14

(B) α is a multiple of 4

(C) 4 is the remainder when α is divided by 10

(D) 4 is the remainder when α is divided by 7

Answer: (D)

9. Out of 60% female and 40% male candidates appearing in an exam, 60% of candidates qualify it. The number of females qualifying the exam is twice the number of males qualifying it. A candidate is randomly chosen from the qualified candidates. The probability that the chosen candidate is a female, is

(A) 3/4

(B) 11/16

(C) 23/32

(D) 13/16

Answer: (A*)

10. If y = y(x), x ∈ (0, π/2) be the solution curve of the differential equation  then y(π/6) is equal to :

Answer: (A)

11. If the tangents drawn at the points P and Q on the parabola y2 = 2x – 3 intersect at the point R(0, 1), then the orthocentre of the triangle PQR is :

(A) (0, 1)

(B) (2, –1)

(C) (6, 3)

(D) (2, 1)

Answer: (B)

12. Let C be the centre of the circle  and P be a point on the circle. A line passes through the point C, makes an angle of π/4 with the line CP and intersects the circle at the Q and R. Then the area of the triangle PQR (in unit2) is :

(A) 2

(B) 2√2

(C) 

(D) 

Answer: (B)

13. The remainder 72022 + 32022 is divided by 5 is:

(A) 0

(B) 2

(C) 3

(D) 4

Answer: (C)

14. Let the matrix  and matrix B0 = A49 + 2A98. If Bn = Adj(Bn–1) for all n ≥ 1, then det(B4) is equal to:

(A) 328

(B) 330

(C) 332

(D) 336

Answer: (C)

15. Let  and S2 = {z2∈C : |z2− |z2 + 1|| = |z2 + |z2 – 1||}. Then, for z1∈ S1 and z2∈ S2, the least value of |z2 – z1| is :

(A) 0

(B) 1/2

(C) 3/2

(D) 5/2

Answer: (C)

16. The foot of the perpendicular from a point on the circle x2 + y2 = 1, z = 0 to the plane 2x + 3y + z = 6 lies on which one of the following curves?

(A) (6x + 5y – 12)2 + 4(3x + 7y – 8)2 = 1, z = 6 – 2x – 3y

(B) (5x + 6y – 12)2 + 4(3x + 5y – 9)2 = 1, z = 6 – 2x – 3y

(C) (6x + 5y – 14)2 + 9(3x + 5y – 7)2 = 1, z = 6 – 2x – 3y

(D) (5x + 6y – 14)2 + 9(3x + 7y – 8)2 = 1, z = 6 – 2x – 3y

Answer: (B)

17. If the minimum value of  is 14, then the value of α is equal to

(A) 32

(B) 64

(C) 128

(D) 256

Answer: (C)

18. Let α, β and γ be three positive real numbers. Let f(x) = αx5 + βx3 + γx, x ∈ R and g : R → R be such that g(f(x)) = x for all x ∈ If a1, a2, a3, …, an be in arithmetic progression with mean zero, then the value of  is equal to

(A) 0

(B) 3

(C) 9

(D) 27

Answer: (A)

19. Consider the sequence a1, a2, a3, … such that a1 = 1, a2 = 2 and  for n = 1, 2, 3, … . If  then α is equal to:

(A) −30

(B) −31

(C) −60

(D) −61

Answer: (C)

20. The minimum value of the twice differentiable function  is :

Answer: (A)

SECTION-B

21. Let S be the set of all passwords which are six to eight characters long, where each character is either an alphabet from {A, B, C, D, E} or a number from {1, 2, 3, 4, 5} with the repetition of characters allowed. If the number of passwords in S whose at least one character is a number from {1, 2, 3, 4, 5} is α × 56, then α is equal to _______.

Answer: (7073)

22. Let P(–2, –1, 1) and  be the vertices of the rhombus PRQS. If the direction ratios of the diagonal RS are α, –1, β, where both α and β are integers of minimum absolute values, then α2 + β2 is equal to ___________.

Answer: (450)

23. Let f : [0, 1] → R be a twice differentiable function in (0, 1) such that f(0) = 3 and f(1) = 5. If the liney = 2x + 3 intersects the graph of f at only two distinct points in (0, 1) then the least number of points x ∈ (0, 1) at which f”(x) = 0, is ___________.

Answer: (2)

24. If  where α, β are integers, then α + β is equal to

Answer: (10)

25. Let  α, β∈ Let α1 be the value of α which satisfies  and α2 be the value of α which satisfies (A + B)2 = B2. Then |α1 – α2| is equal to ________.

Answer: (2)

26. For p, q, ∈ R, consider the real valued function f(x) = (x – p)2 – q, x ∈ R and q > 0, Let a1, a2, a3 and a4 be in an arithmetic progression with mean p and positive common difference. If |f(ai)| = 500 for all i = 1, 2, 3, 4, then the absolute difference between the roots of f(x) = 0 is

Answer: (50)

27. For the hyperbola H: x2 – y2 = 1 and the ellipse  let the

(1) eccentricity of E be reciprocal of the eccentricity of H, and

(2) the line  be a common tangent of E and H.

Then 4(a2 + b2) is equal to _________.

Answer: (3)

28. Let x1, x2, x3, …, x20 be in geometric progression with x1 = 3 and the common ratio 1/2. A new data is constructed replacing each xi by (xi – i)2. If  is the mean of new data, then the greatest integer less than or equal to  is _________.

Answer: (142)

29. is equal to _______.

Answer: (1)

30. The sum of all real value of x for which  is equal to ________.

Answer: (6)

JEE Main Session 1 27th July 2022 Shift 1 Question Paper and Answer Key

JEE Main Session 1 27th July 2022 Shift 1

PHYSICS

SECTION-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii)   Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. A torque meter is calibrated to reference standards of mass, length and time each with 5% accuracy. After calibration, the measured torque with this torque meter will have net accuracy of :

(A)  15%

(B)  25%

(C)  75%

(D)  5%

Answer: (B)

2. A bullet is shot vertically downwards with an initial velocity of 100 m/s from a certain height. Within 10 s, the bullet reaches the ground and instantaneously comes to rest due to the perfectly inelastic collision. The velocity-time curve for total time t = 20 s will be : (Take g = 10 m/s2)

Answer: (A)

3. Sand is being dropped from a stationary dropper at a rate of 0.5 kgs–1 on a conveyor belt moving with a velocity of 5 ms–1. The power needed to keep belt moving with the same velocity will be :

(A)  1.25 W

(B)  2.5 W

(C)  6.25 W

(D)  12.5 W

Answer: (D)

4. A bag is gently dropped on a conveyor belt moving at a speed of 2 m/s. The coefficient of friction between the conveyor belt and bag is 0.4 Initially, the bag slips on the belt before it stops due to friction. The distance travelled by the bag on the belt during slipping motion is : [Take g = 10 m/s–2]

(A)  2 m

(B)  0.5 m

(C)  3.2 m

(D)  0.8 ms

Answer: (B)

5. Two cylindrical vessels of equal cross-sectional area 16 cm2 contain water upto heights 100 cm and 150 cm respectively. The vessels are interconnected so that the water levels in them become equal. The work done by the force of gravity during the process, is [Take density of water = 103 kg/m3 and g = 10 ms–2]

(A)  0.25 J

(B)  1 J

(C)  8 J

(D)  12 J

Answer: (B)

6. Two satellites A and B having masses in the ratio 4:3 are revolving in circular orbits of radii 3r and 4 r respectively around the earth. The ratio of total mechanical energy of A to B is :

(A)  9 : 16

(B)  16 : 9

(C)  1 : 1  

(D)  4 : 3

Answer: (B)

7. If K1 and K2 are the thermal conductivities L1 and L2 are the lengths and A1 and A2 are the cross sectional areas of steel and copper rods respectively such that  Then, for the arrangement as shown in the figure. The value of temperature T of the steel – copper junction in the steady state will be :

(A)  18°C

(B)  14°C

(C)  45°C

(D)  150°C

Answer: (C)

8. Read the following statements :

(A) When small temperature difference between a liquid and its surrounding is doubled the rate of loss of heat of the liquid becomes twice. 

(B) Two bodies P and Q having equal surface areas are maintained at temperature 10ºC and 20ºC. The thermal radiation emitted in a given time by P and Q are in the ratio 1 : 1.15 

(C) A carnot Engine working between 100 K and 400 K has an efficiency of 75% 

(D) When small temperature difference between a liquid and its surrounding is quadrupled, the rate of loss of heat of the liquid becomes twice. 

Choose the correct answer from the options given below :

(A) A, B, C only

(B) A, B only 

(C) A, C only

(D) B, C, D only

Answer: (A)

9. Same gas is filled in two vessels of the same volume at the same temperature. If the ratio of the number of molecules is 1:4, then

(A) The r.m.s. velocity of gas molecules in two vessels will be the same. 

(B) The ratio of pressure in these vessels will  be 1 : 4 

(C) The ratio of pressure will be 1 : 1 

(D) The r.m.s. velocity of gas molecules in two vessels will be in the ratio of 1 : 4

(A) A and C only

(B) B and D only 

(C) A and B only

(D) C and D only

Answer: (C)

10. Two identical positive charges Q each are fixed at a distance of ‘2a’ apart from each other. Another point charge q0 with mass ‘m’ is placed at midpoint between two fixed charges. For a small displacement along the line joining the fixed charges, the charge q0 executes SHM. The time period of oscillation of charge q0will be :

Answer: (A)

11. Two sources of equal emfs are connected in series. This combination is connected to an external resistance R. The internal resistances of the two sources are r1 and r2 (r1> r2). If the potential difference across the source of internal resistance r1 is zero then the value of R will be

(A)  r – r­2

(B) 

(C) 

(D)  r2 – r1

Answer: (A)

12. Two bar magnets oscillate in a horizontal plane in earth’s magnetic field with time periods of 3 s and 4 s respectively. If their moments of inertia are in the ratio of 3 : 2 then the ratio of their magnetic moments will e :

(A)  2 : 1

(B)  8 : 3

(C)  1 : 3

(D)  27 : 16

Answer: (B)

13. A magnet hung at 45º with magnetic meridian makes an angle of 60º with the horizontal. The actual value of the angle of dip is

Answer: (A)

14. A direct current of 4 A and an alternating current of peak value 4 A flow through resistance of 3Ω and 2Ω The ratio of heat produced in the two resistances in same interval of time will be :

(A)  3 : 2

(B)  3 : 1

(C)  3 : 4

(D)  4 : 3

Answer: (B)

15. A beam of light travelling along X-axis is described by the electric field  Ey = 900 sin ω(t–x/c). The ratio of electric force to magnetic force on a charge q moving along Y-axis with a speed of 3 × 107ms–1 will be :   [Given speed of light = 3 × 108ms–1]

(A)  1 : 1

(B)  1 : 10

(C)  10 : 1

(D)  1 : 2

Answer: (C)

16. A microscope was initially placed in air (refractive index 1). It is then immersed in oil (refractive index 2). For a light whose wavelength in air is λ, calculate the change of microscope’s resolving power due to oil and choose the correct option

(A)  Resolving power will be 1/4 in the oil than it was in the air

(B)  Resolving power will be twice in the oil than it was in the air.

(C)  Resolving power will be four times in the oil than it was in the air.

(D)  Resolving power will be 1/2 in the oil than it was in the air.

Answer: (C)

17. An electron (mass m) with an initial velocity  is moving in an electric field  where E0 is constant. If at t = 0 de Broglie wavelength is  then its de Broglie wavelength after time t is given by

(A)  λ0

(B) 

(C)  λ0t

(D)  

Answer: (D)

18. What is the half-life period of a radioactive material if its activity drops to 1/16th of its initial value of 30 years ?

(A)  9.5 years

(B)  8.5years

(C)  7.5years

(D)  10.5years

Answer: (C)

19. A logic gate circuit has two inputs A and B and output Y. The voltage waveforms of A, B and Y are shown below

The logic gate circuit is

(A) AND gate

(B) OR gate 

(C) NOR gate

(D) NAND gate

Answer: (A)

20. At a particular station, the TV transmission tower has a height of 100 m. To triple its coverage range, height of the tower should be increased to

(A) 200 m

(B) 300 m 

(C) 600 m 

(D) 900 m

Answer: (D)

SECTION-B

21. In meter bridge experiment for measuring unknown resistance ‘S’, the null point is obtained at a distance 30 cm from the left side as shown at point D. If R is 5.6 kΩ, then the value of unknown resistance ‘S’ will be _______ Ω.

Answer: (2400)

22. The one division of main scale of vernier callipers reads 1 mm and 10 divisions of Vernier scale is equal to the 9 divisions on main scale. When the two jaws of the instrument touch each other the zero of the Vernier lies to the right of zero of the main scale and its fourth division coincides with a main scale division. When a spherical bob is tightly placed between the two jaws, the zero of the Vernier scale lies in between 4.1 cm and 4.2 cm and 6th Vernier division coincides with a main scale division. The diameter of the bob will be_____ 10–2

Answer: (412)

23. Two beams of light having intensities I and 4I interfere to produce a fringe pattern on a screen. The phase difference between the two beams areπ/2 and π/3 at points A and B respectively. The difference between the resultant intensities at the two points is xI. The value of x will be ______ .

Answer: (2)

24. To light, a 50 W, 100 V lamp is connected, in series with a capacitor of capacitance  with 200 V, 50Hz AC source. The value of x will be ____ .

Answer: (3)

25. A 1 m long copper wire carries a current of 1 A. If the cross section of the wire is 2.0 mm2 and the resistivity of copper is 1.7 × 10–8Ω the force experienced by moving electron in the wire is ______ × 10–23 N. (charge on electron  = 1.6 × 10–19 C)

Answer: (136)

26. A long cylindrical volume contains a uniformly distributed charge of density ρ Cm–3. The electric field inside the cylindrical volume at a distance  from its axis is ________ Vm1

Answer: (1)

27. A mass 0.9 kg, attached to a horizontal spring, executes SHM with an amplitude A1. When this mass passes through its mean position, then a smaller mass of 124 g is placed over it and both masses move together with amplitude A2. If  the then the value of αwill be ____ .

Answer: (16)

28. A square aluminium (shear modulus is 25 × 109 Nm–2) slab of side 60 cm and thickness  15 cm is subjected to a shearing force (on its narrow face) of 18.0 × 104 The lower edge is riveted to the floor. The displacement of the upper edge is ________ μm.

Answer: (48)

29. A pulley of radius 1.5 m is rotated about its axis by a force F = (12t – 3t2) N applied tangentially (while t is measured in seconds). If moment of inertia of the pulley about its axis of rotation is 4.5 kg m2, the number of rotations made by the pulley before its direction of motion is reversed, will be K/π.The value of K is _______ .

Answer: (18)

30. A ball of mass m is thrown vertically upward. Another ball of mass 2 m is thrown an angle θ with the vertical. Both the balls stay in air for the same period of time. The ratio of the heights attained by the two balls respectively is 1/x. The value of x is _______.

Answer: (1)

CHEMISTRY

SECTION-A

1. 250 g solution of D-glucose in water contains 10.8% of carbon by weight. The molality of the solution is nearest to

(Given: Atomic Weights are H, 1u ; C, 12u ; O, 16u)

(A)  1.03

(B)  2.06

(C)  3.09

(D)  5.40

Answer: (B)

2. Given below are two statements.  

Statement I : O2 , Cu2+ and Fe3+ are weakly attracted by magnetic field and are magnetized in the same direction as magnetic field. 

Statement II : NaCl and H2O are weakly magnetized in opposite direction to magnetic field. 

In the light of the above statements, choose the most appropriate answer form the options given below :

(A) Both Statement I and Statement II are correct.  

(B) Both Statement I and Statement II are incorrect. 

(C) Statement I is correct but Statement II is incorrect.   

(D) Statement I is incorrect but Statement II is correct.

Answer: (A)

3. Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : Energy of 2s orbital of hydrogen atom is greater than that of 2s orbital of lithium.

Reason R : Energies of the orbitals in the same subshell decrease with increase in the atomic number.

In the light of the above statements, choose the correct answer from the options given below.

(A) Both A and R are true and R is the correct explanation of A.  

(B) Both A and R are true but R is NOT the correct explanation of A. 

(C) A is true but R is false.  

(D) A is false but R is true.

Answer: (A)

4. Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Activated charcoal adsorbs SO2 more efficiently than CH4

Reason R: Gases with lower critical temperatures are readily adsorbed by activated charcoal.

In the light of the above statements, choose the correct answer from the options given below. 

(A) Both A and R are correct and R is the correct explanation of A.  

(B) Both A and R are correct but R is NOT the correct explanation of A. 

(C) A is correct but R is not correct.  

(D) A is not correct but R is correct.

Answer: (C)

5. Boiling point of a 2% aqueous solution of a nonvolatile solute A is equal to the boiling point of 8% aqueous solution of a non-volatile solute B. The relation between molecular weights of A and B is.

(A) MA = 4MB

(B) MB = 4MA

(C) MA = 8MB

(D) MB = 8MA

Answer: (B)

6. The incorrect statement is

(A) The first ionization enthalpy of K is less than that of Na and Li 

(B) Xe does not have the lowest first ionization enthalpy in its group 

(C) The first ionization enthalpy of element with atomic number 37 is lower than that of the element with atomic number 38. 

(D) The first ionization enthalpy of Ga is higher than that of the d-block element with atomic number 30.

Answer: (D)

7. Which of the following methods are not used to refine any metal?  

(A) Liquation

(B) Calcination 

(C) Electrolysis

(D) Leaching 

(E) Distillation  Choose the correct answer from the options given below:

(A) B and D only 

(B) A, B, D and E only 

(C) B, D and E only

(D) A, C and E only

Answer: (A)

8. Given below are two statements:

Statement I: Hydrogen peroxide can act as an oxidizing agent in both acidic and basic conditions. 

Statement II: Density of hydrogen peroxide at 298 K is lower than that of D2O. 

In the light of the above statements. Choose the correct answer from the options. 

(A) Both statement I and Statement II are true  

(B) Both statement I and Statement II are false 

(C) Statement I is true but Statement II is false 

(D) Statement I is false but Statement II is true

Answer: (C)

9. Given below are two statements:

Statement I : The chlorides of Be and Al have   Cl-bridged structure. Both are soluble in organic solvents and act as Lewis bases. 

Statement II: Hydroxides of Be and Al dissolve in excess alkali to give beryllate and aluminate ions.   In the light of the above statements.

Choose the correct answer from the options given below.

(A) Both statement I and Statement II are true  

(B) Both statement I and Statement II are false 

(C) Statement I is true but Statement II is false 

(D) Statement I is false but Statement II is true

Answer: (D)

10. Which oxoacid of phosphorous has the highest number of oxygen atoms present in its chemical formula?

(A) Pyrophosphorous acid 

(B) Hypophosphoric acid 

(C) Phosphoric acid 

(D) Pyrophosphoric acid

Answer: (D)

11. Given below are two statements:

Statement I: Iron (III) catalyst, acidified K2Cr2O7 and neutral KMnO4 have the ability to oxidise I to I2 independently. 

Statement II: Manganate ion is paramagnetic in nature and involves pπ–pπ bonding. 

In the light of the above statements, choose the correct answer from the options. 

(A) Both statement I and Statement II are true  

(B) Both statement I and Statement II are false 

(C) Statement I is true but Statement II is false 

(D) Statement I is false but Statement II is true

Answer: (B)

12. The total number of Mn = O bonds in Mn2O7 is ____

(A)  4

(B)  5

(C)  6

(D)  3

Answer: (C)

13. Match List I with List II

Choose the correct answer from the options given below: 

(A) A-IV, B –I, C-II, D-III 

(B) A-III, B –I, C-IV, D-II 

(C) A-II, B –IV, C-I, D-III 

(D) A-II, B –IV, C-III, D-I

Answer: (B)

14. Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A :    [6] Annulene. [8] Annulene and cis–[10] Annulene, are respectively aromatic,            not-aromatic and aromatic.

Reason R: Planarity is one of the requirements of aromatic systems.

In the light of the above statements, choose the most appropriate answer from the options given below. 

(A) Both A and R are correct and R is the correct explanation of A.  

(B) Both A and R are correct but R is NOT the correct explanation of A. 

(C) A is correct but R is not correct.  

(D) A is not correct but R is correct. 

Answer: (A)

15. 

In the above reaction product B is:

Answer: (A)

16. Match List I with List II 

Choose the correct answer from the options given below: 

(A) A-II, B –III, C-IV, D-I 

(B) A-II, B –III, C-I, D-IV 

(C) A-II, B –I, C-III, D-IV 

(D) A-III, B –II, C-IV, D-I

Answer: (B)

17. A sugar ‘X’ dehydrates very slowly under acidic condition to give furfural which on further reaction with resorcinol gives the coloured product after sometime. Sugar ‘X’ is

(A)  Aldopentose

(B)  Aldotetrose

(C)  Oxalic acid

(D)  Ketotetrose

Answer: (A)

18. Match List I with List II

Choose the correct answer from the options given below:  

(A) A-IV, B –III, C-II, D-I 

(B) A-III, B –I, C-II, D-IV 

(C) A-III, B –IV, C-I, D-II 

(D) A-III, B –I, C-IV, D-II

Answer: (C)

19. In Carius method of estimation of halogen. 0.45 g of an organic compound gave 0.36 g of AgBr. Find out the percentage of bromine in the compound.

(Molar masses :AgBr = 188 g mol1: Br = 80 g mol1

(A)  34.04%

(B)  40.04%

(C)  36.03%

(D)  38.04%

Answer: (A)

20. Match List I with List II

Choose the correct answer from the options given below: 

(A) A-IV, B –III, C-II, D-I 

(B) A-IV, B –II, C-I, D-III 

(C) A-III, B –IV, C-I, D-II 

(D) A-IV, B –III, C-I, D-II

Answer: (C)

SECTION-B

21. 20 mL of 0.02 M K2Cr2O7 solution is used for the titration of 10 mL of Fe2+ solution in the acidic medium. The molarity of Fe2+ solution is ______ × 102 (Nearest Integer)

Answer: (24)

22. 2NO + 2H2→ N2 + 2H2O

The above reaction has been studied at 800°C. The related data are given in the table below

The order of the reaction with respect to NO is______

Answer: (2)

23. Amongst the following the number of oxide(s) which are paramagnetic in nature is

Na2O, KO2, NO2, N2O, ClO2, NO, SO2, Cl2O

Answer: (4)

24. The molar heat capacity for an ideal gas at constant pressure is 20.785 J K1mol1. The change in internal energy is 5000 J upon heating it from 300K to 500K. The number of moles of the gas at constant volume is ___ [Nearest integer]

(Given: R = 8.314 J K1 mol1)

Answer: (2)

25. According to MO theory, number of species/ions from the following having identical bond order is_____:

CN, NO+, O2, O2+, O22+

Answer: (3)

26. At 310 K, the solubility of CaF2 in water is 34 × 103g /100 mL. The solubility product of CaF2 is __________ × 108 (mol/L)3. (Given molar mass : CaF2 = 78 g mol1)

Answer: (0)

27. The conductivity of a solution of complex with formula CoCl3(NH3)4 corresponds to 1 : 1 electrolyte, then the primary valency of central metal ion is______

Answer: (1)

28. In the titration of KMnO4 and oxalic acid in acidic medium, the change in oxidation number of carbon at the end point is_____

Answer: (1)

29. Optical activity of an enantiomeric mixture is +12.6° and the specific rotation of (+) isomer is +30°. The optical purity is______%

Answer: (42)

30. In the following reaction

The % yield for reaction I is 60% and that of reaction II is 50%. The overall yield of the complete reaction is _______% [nearest integer]

Answer: (30)

MATHEMATICS

SECTION-A

1. Let R1 and R2 be two relations defined on ℝ by a R1b ⇔ab ≥ 0 and aR2b ⇔ a ≥ b. Then,

(A) R1 is an equivalence relation but not R2

(B) R2 is an equivalence relation but not R1

(C) Both R1 and R2 are equivalence relations

(D) Neither R1 nor R2 is an equivalence relation

Answer: (D)

2. Let f , g : ℕ − {1} → ℕ be functions defined by f(a) = α, where α is the maximum of the powers of those primes p such that pα divides a, and g(a) = a + 1, for all a ∈ N – {1}. Then, the function  f + g is

(A) One-one but not onto

(B) Onto but not one-one

(C) Both one-one and onto

(D) Neither one-one nor onto

Answer: (D)

3. Let the minimum value v0 of v = |z|2 + |z – 3|2 + |z – 6i|2, z ∈ ℂ is attained at z = z0. Then  is equal to

(A)  1000

(B)  1024

(C)  1105

(D)  1196

Answer: (A)

4. Let  Let α, β ∈ ℝ be such that αA2 + βA = 2I. Then α + β is equal to-

(A)  −10

(B)  −6

(C)  6

(D)  10

Answer: (D)

5. The remainder when (2021)2022 + (2022)2021 is divided by 7 is

(A)  0

(B)  1

(C)  2

(D)  6

Answer: (A)

6. Suppose a1, a2, … an, … be an arithmetic progression of natural numbers. If the ration of the sum of first five terms to the sum of first nine terms of the progression is 5 : 17 and 110 < a15< 120, then the sum of the first ten terms of the progression is equal to

(A)  290

(B)  380

(C)  460

(D)  510

Answer: (B)

7. Let ℝ → ℝ be function defined as  where [t] is the greatest integer less than or equal to t. If  exists, then the value of  is equal to :

(A)  −1

(B)  −2

(C)  1

(D)  2

Answer: (B)

8.  Then

Answer: (C)

9. The area of the smaller region enclosed by the curves y2 = 8x + 4 and x2 + y2 + 4√3x – 4 = 0 is equal to

Answer: (C)

10. Let y = y1(x) and y = y2(x) be two distinct solution of the differential equation  with y1(0) = 0 and y2(0) = 1 respectively. Then, the number of points of intersection of y = y1(x) and y = y2(x) is

(A)  0

(B)  1

(C)  2

(D)  3

Answer: (A)

11. Let P(a, b) be a point on the parabola y2 = 8x such that the tangent at P passes through the centre of the circle x2 + y2 – 10x – 14y + 65 = 0. Let A be the product of all possible values of a and B be the product of all possible values of b. Then the value of A + B is equal to

(A)  0

(B)  25

(C)  40

(D)  65

Answer: (D)

12. Let  be two vectors, such that  Then the projection of  is equal to

(A)  2

(B)  39/5

(C)  9

(D)  46/5

Answer: (D)

13. Let  If  is equal to

(A)  4

(B)  5

(C)  √21

(D)  √17

Answer: (B)

14. Let S be the sample space of all five digit numbers. It p is the probability that a randomly selected number from S, is multiple of 7 but not divisible by 5, then 9p is equal to

(A)  1.0146

(B)  1.2085

(C)  1.0285

(D)  1.1521

Answer: (C)

15. Let a vertical tower AB of height 2h stands on a horizontal ground. Let from a point P on the ground a man can see upto height h of the tower with an angle of elevation 2α. When from P, he moves a distance d in the direction of  he can see the top B of the tower with an angle of elevation α. if d = √7 h, then tan α is equal to

(A)  √5 − 2

(B)  √3− 1

(C)  √7− 2

(D)  √7−√3

Answer: (C)

16. (p ∧ r) ⟺ (p ∧ (~q)) is equivalent to (~ p) when r is

(A)  p

(B)  ~p

(C)  q

(D)  ~q

Answer: (C)

17. If the plane P passes through the intersection of two mutually perpendicular planes 2x + ky – 5z = 1 and 3kx – ky + z = 5, k < 3 and intercepts a unit length on positive x-axis, then the intercept made by the plane P on the y-axis is

(A)  1/11

(B)  5/11

(C)  6

(D)  7

Answer: (D)

18. Let A(1, 1), B(-4, 3) and C(-2, -5) be vertices of a triangle ABC, P be a point on side BC, and Δ1 and Δ2 be the areas of triangles APB and ABC, respectively. If Δ1 : Δ2 = 4 : 7, then the area enclosed by the lines AP, AC and the x-axis is

(A)  1/4

(B)  3/4

(C)  1/2

(D)  1

Answer: (C)

19. If the circle x2 + y2 – 2gx + 6y – 19c = 0, g, c ∈ℝ passes through the point (6, 1) and its centre lies on the line x – 2cy = 8, then the length of intercept made by the circle on x-axis is

(A)  √11

(B)  4

(C)  3

(D)  2√23

Answer: (D)

20. Let a function f: ℝ → ℝ be defined as :

where b ∈ℝ. If f is continuous at x = 4 then which of the following statements is NOT true?

(A)  f is not differentiable at x = 4

(B) 

(C)  f is increasing in 

(D)  f has a local minima at x = 1/8

Answer: (C)

SECTION-B

21. For k ∈ R, let the solution of the equation cos(sin1(x cot(tan1(cos(sin1))))) = k, . Inverse trigonometric functions take only principal values. If the solutions of the equation x2 – bx – 5 = 0 are , then b/k2 is equal to ________.

Answer: (12)

22. The mean and variance of 10 observation were calculated as 15 and 15 respectively by a student who took by mistake 25 instead of 15 for one observation. Then, the correct standard deviation is ________.

Answer: (2)

23. Let the line  intersect the plane containing the lines  and 4ax – y + 5z – 7a = 0 = 2x – 5y – z – 3, a ∈ℝ at the point P(α, β, γ). Then the value of α + β + γ equals _____.

Answer: (12)

24. An ellipse  passes through the vertices of the hyperbola . Let the major and minor axes of the ellipse E coincide with the transverse and conjugate axes of the hyperbola H, respectively. Let the product of the eccentricities of E and H be 1/2. If the length of the latus rectum of the ellipse E, then the value of 113l is equal to ________.

Answer: (1552)

25. Let y = y(x) be the solution curve of the differential equation  which passes through the point  is equal to __________.

Answer: (1)

26. Let M and N be the number of points on the curve y5 – 9xy + 2x = 0, where the tangents to the curve are parallel to x-axis and y-axis, respectively. Then the value of M + N equals ________.

Answer: (2)

27. Let f(x) = 2x2 – x – 1 and S = {n ∈ℤ : |f(n) ≤ 800}. Then, the value of  is equal to _________.

Answer: (10620)

28. Let S be the set containing all 3 × 3 matrices with entries from {−1, 0, 1}. The total number of matrices A∈ S such that the sum of all the diagonal elements of AT A is 6 is ________.

Answer: (5376)

29. If the length of the latus rectum of the ellipse x2 + 4y2 + 2x + 8y – λ = 0 is 4, and l is the length of its major axis, then λ + l is equal to ________.

Answer: (75)

30. Let  Then  is equal to _________.

Answer: (0)

JEE Main Session 1 26th July 2022 Shift 1 Question Paper and Answer Key

JEE Main Session 1 26th July 2022 Shift 1

PHYSICS

SECTION-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii)   Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. Three masses M = 100 kg, m1 = 10 kg and m2 = 20 kg are arranged in a system as shown in figure. All the surfaces are frictionless and strings are inextensible and weightless. The pulleys are also weightless and frictionless. A force F is applied on the system so that the mass m2 moves upward with an acceleration of 2 ms–2. The value of F is

(Take g = 10 ms–2)

(A)  3360 N

(B)  3380 N

(C)  3120 N

(D)  3240 N

Answer: (C)

2. A radio can tune to any station in 6 MHz to 10 MHz band. The value of corresponding wavelength bandwidth will be

(A)  4 m

(B)  20 m

(C)  30 m

(D)  50 m

Answer: (B)

3. The disintegration rate of a certain radioactive sample at any instant is 4250 disintegrations per minute. 10 minutes later, the rate becomes 2250 disintegrations per minute. The approximate decay constant is

(Take log101.88 = 0.274)

(A) 0.02 min–1

(B) 2.7 min–1

(C) 0.063 min–1

(D) 6.3 min–1

Answer: (C)

4. A parallel beam of light of wavelength 900 nm and intensity 100 Wm–2 is incident on a surface perpendicular to the beam. The number of photons crossing 1 cm–2 area perpendicular to the beam in one second is

(A) 3 × 1016

(B) 4.5 × 1016

(C) 4.5 × 1017

(D) 4.5 × 1020

Answer: (B)

5. In Young’s double slit experiment, the fringe width is 12 mm. If the entire arrangement is placed in water of refractive index 4/3, then the fringe width becomes (in mm)

(A)  16

(B)  9

(C)  48

(D)  12

Answer: (B)

6. The magnetic field of a plane electromagnetic wave is given by

The amplitude of the electric field would be

(A) 6 Vm–1 along x-axis

(B) 3 Vm–1 along z-axis

(C) 6 Vm–1 along z-axis

(D) 2 × 10–8Vm–1 along z-axis

Answer: (C)

7. In a series LR circuit XL = R and power factor of the circuit is P1. When capacitor with capacitance C such that XL = XC is put in series, the power factor becomes P2. The ratio P1/P2 is

(A)  1/2

(B)  1/√2

(C)  √3/√2

(D)  2 : 1

Answer: (B)

8. A charge particle is moving in a uniform field  If it has an acceleration of  then the value of α will be

(A)  3

(B)  6

(C)  12

(D)  2

Answer: (B)

9. BX and BY are the magnetic field at the centre of two coils X and Y, respectively each carrying equal current. If coil X has 200 turns and 20 cm radius and coil Y has 400 turns and 20 cm radius, the ratio of BX and BY is

(A)  1 : 1

(B)  1 : 2

(C)  2 : 1

(D)  4 : 1

Answer: (B)

10. The current I in the given circuit will be

(A)  10 A

(B)  20 A

(C)  4 A

(D)  40 A

Answer: (A)

11. The total charge on the system of capacitors C1 = 1μF, C2 = 2μF, C3 = 4μF and C4 = 3μF connected in parallel is :

(Assume a battery of 20 V is connected to the combination)

(A) 200 μC

(B) 200 C

(C) 10 μC

(D) 10 C

Answer: (A)

12. When a particle executes Simple Harmonic Motion, the nature of graph of velocity as a function of displacement will be :

(A) Circular

(B) Elliptical

(C) Sinusoidal

(D) Straight line

Answer: (B)

13. 7 mol of a certain monoatomic ideal gas undergoes a temperature increase of 40 K at constant pressure. The increase in the internal energy of the gas in this process is :

(Given R = 8.3 JK–1mol–1)

(A)  5810 J

(B)  3486 J

(C)  11620 J

(D)  6972 J

Answer: (B)

14. A monoatomic gas at pressure P and volume V is suddenly compressed to one eighth of its original volume. The final pressure at constant entropy will be :

(A)  P

(B)  8P

(C)  32P

(D)  64P

Answer: (C)

15. A water drop of radius 1 cm is broken into 729 equal droplets. If surface tension of water is 75 dyne/cm, then the gain in surface energy upto first decimal place will be :

(Given π = 3.14)

(A) 8.5 × 10–4 J

(B) 8.2 × 10–4 J

(C) 7.5 × 10–4 J

(D) 5.3 × 10–4 J

Answer: (C)

16. The percentage decrease in the weight of a rocket, when taken to a height of 32 km above the surface of earth will, be:

(Radius of earth = 6400 km)

(A)  1%

(B)  3%

(C)  4%

(D)  0.5%

Answer: (A)

17. As per the given figure, two blocks each of mass 250 g are connected to a spring of spring constant 2 Nm–1. If both are given velocity v in opposite directions, then maximum elongation of the spring is:

(A)  v/2√2

(B)  v/2

(C)  v/4

(D)  v/√2

Answer: (B)

18. A monkey of mass 50 kg climbs on a rope which can withstand the tension (T) of 350 N. If monkey initially climbs down with an acceleration of 4 m/s2 and then climbs up with an acceleration of 5 m/s2. Choose the correct option (g = 10 m/s2).

(A) T = 700 N while climbing upward

(B) T = 350 N while going downward

(C) Rope will break while climbing upward

(D) Rope will break while going downward

Answer: (C)

19. Two projectiles thrown at 30° and 45° with the horizontal, respectively, reach the maximum height in same time. The ratio of their initial velocities is :

(A)  1 :√2

(B)  2 : 1

(C)  √2 : 1

(D)  1 : 2

Answer: (C)

20. A screw gauge of pitch 0.5 mm is used to measure the diameter of uniform wire of length 6.8 cm, the main scale reading is 1.5 mm and circular scale reading is 7. The calculated curved surface area of wire to appropriate significant figures is :

[Screw gauge has 50 divisions on its circular scale]

(A)  6.8 cm2

(B)  3.4cm2

(C)  3.9cm2

(D)  2.4cm2

Answer: (B)

SECTION-B

21. If the initial velocity in horizontal direction of a projectile is unit vector  and the equation of trajectory is y = 5x(1 – x). The y component vector of the initial velocity is ______ 

(Take g = 10 m/s2)

Answer: (5)

22. A disc of mass 1 kg and radius R is free to rotate about a horizontal axis passing through its centre and perpendicular to the plane of disc. A body of same mass as that of disc of fixed at the highest point of the disc. Now the system is released, when the body comes to the lowest position, it angular speed will be  where x = ______

(g = 10 ms2)

Answer: (5)

23. In an experiment of determine the Young’s modulus of wire of a length exactly 1 m, the extension in the length of the wire is measured as 0.4 mm with an uncertainty of ±0.02 mm when a load of 1 kg is applied. The diameter of the wire is measured as 0.4 mm with an uncertainty of ±0.02 mm when a load of 1 kg is applied. The diameter of the wire is measured as 0.4 mm with an uncertainty of ±0.01 mm. The error in the measurement of Young’s modulus (ΔY) is found to be x × 1010 Nm–2. The value of x is ______.

(Take g = 10 m/s2)

Answer: (2)

24. When a car is approaching the observer, the frequency of horn is 100 Hz. After passing the observer, it is 50 Hz. If the observer moves with the car, the frequency will be x/3 Hz where x = ________.

Answer: (200)

25. A composite parallel plate capacitor is made up of two different dielectric materials with different thickness (t1 and t2) as shown in figure. The two different dielectric materials are separated by a conducting foil F. The voltage of the conducting foil is ________V.

Answer: (60)

26. Resistances are connected in a meter bridge circuit as shown in the figure. The balancing length l1 is 40 cm. Now an unknown resistance x is connected in series with P and new balancing length is found to be 80 cm measured from the same end. Then the value of x will be ________ Ω.

Answer: (20)

27. The effective current I in the given circuit at very high frequencies will be ________ A.

Answer: (44)

28. The graph between 1/u and 1/v for a thin convex lens in order to determine its focal length is plotted as shown in the figure. The refractive index of lens is 1.5, and its both the surfaces have the same radius of curvature R. The value of R will be______ cm.

(where u = object distance, v = image distance)

Answer: (10)

29. In the hydrogen spectrum, λ be the wavelength of first transition line of Lyman series. The wavelength difference will be “aλ” between the wavelength of 3rd transition line of the Paschen series and that of 2nd transition line of Balmer series where a = _______.

Answer: (5)

30. In the circuit shown below, maximum Zener diode current will be ________ mA.

Answer: (9)

CHEMISTRY

SECTION-A

1. Match List – I with List – II.

Choose the correct answer from the options given below :

(A) (A) – (I), (B) – (II), (C) – (III), (D) – (IV)

(B) (A) – (IV), (B) – (III), (C) – (II), (D) – (I)

(C) (A) – (II), (B) – (IV), (C) – (I), (D) – (III)

(D) (A) – (III), (B) – (IV), (C) – (II), (D) – (I)

Answer: (C)

2. Match List – I with List – II.

Choose the correct answer from the options given below :

(A) (A) – (III), (B) – (I), (C) – (II), (D) – (IV)

(B) (A) – (III), (B) – (II), (C) – (I), (D) – (IV)

(C) (A) – (IV), (B) – (III), (C) – (I), (D) – (II)

(D) (A) – (IV), (B) – (II), (C) – (III), (D) – (I)

Answer: (B)

3. Given two statements below :

Statement I: In Cl2 molecule the covalent radius is double of the atomic radius of chlorine.

Statement II: Radius of anionic species is always greater than their parent atomic radius.  Choose the most appropriate answer from options given below :

(A) Both Statement I and Statement II are correct.

(B) Both Statement I and Statement II are incorrect.

(C) Statement I is correct but Statement II is incorrect.

(D) Statement I is incorrect but Statement II is                 correct.

Answer: (D)

4. Refining using liquation method is the most suitable for metals with :

(A) Low melting point

(B) High boiling point

(C) High electrical conductivity

(D) Less tendency to be soluble in melts than impurities

Answer: (A)

5. Which of the following can be used to prevent the decomposition of H2O2?

(A) Urea

(B) Formaldehyde

(C) Formic acid

(D) Ethanol

Answer: (A)

6. Reaction of BeCl2 with LiAlH4 gives :

(A) AlCl3

(B) BeH2

(C) LiH

(D) LiCl

(E) BeAlH4

Choose the correct answer from options given below :

(A) (A), (D) and (E)

(B) (A) , (B) and (D)

(C) (D) and (E)

(D) (B) , (C) and (D)

Answer: (B)

7. Borazine, also known as inorganic benzene, can be prepared by the reaction of 3-equivalents of “X” with 6-equivalents of “Y”. “X” and “Y”, respectively are :

(A) B(OH)3 and NH3

(B) B2H6 and NH3

(C) B2H6 and HN3

(D) NH3 and B2O3

Answer: (B)

8. Which of the given reactions is not an example of disproportionation reaction ?

(A) 2H2O2→ 2H2O + O2

(B) 2NO2 + H2O → HNO3 + HNO2

(C) MnO4 + 4H+ + 3e→ MnO2 + 2H2O

(D) 3MnO42– + 4H+ → 2MnO4 + MnO2 + 2H2O

Answer: (C)

9. The dark purple colour of KMnO4 disappears in the titration with oxalic acid in acidic medium.  The overall change in the oxidation number of manganese in the reaction is :

(A)  5

(B)  1

(C)  7

(D)  2

Answer: (A)

10. 

A and B in the above atmospheric reaction step are

(A)  C2H6 and Cl2

(B) 

(C) 

(D)  CH6 and HCl

Answer: (C)

11. Which technique among the following, is most appropriate in separation of a mixture of 100 mg of p-nitrophenol and picric acid ?

(A) Steam distillation

(B) 2-5 ft long column of silica gel

(C) Sublimation

(D)Preparative TLC (Thin Layer Chromatography)

Answer: (D)

12. The difference in the reaction of phenol with bromine in chloroform and bromine in water medium is due to :

(A) Hyperconjugation in substrate

(B) Polarity of solvent

(C) Free radical formation

(D) Electromeric effect of the substrate

Answer: (B)

13. Which of the following compounds is not aromatic?

Answer: (C)

14. The products formed in the following reaction, A and B are

Answer: (C)

15. Which reactant will give the following alcohol on reaction with one mole of phenyl magnesium bromide (PhMgBr) followed by acidic hydrolysis ?

Answer: (D)

16. The major product of the following reaction is

Answer: (A)

17. The correct stability order of the following diazonium salt is

(A) (A) > (B) > (C) > (D)

(B) (A) > (C) > (D) > (B)

(C) (C) > (A) > (D) > (B)

(D) (C) > (D) > (B) > (A)

Answer: (B)

18. Stearic acid and polyethylene glycol react to form which one of the following soap/s detergents ?

(A) Cationic detergent

(B) Soap

(C) Anionic detergent

(D) Non-ionic detergent

Answer: (D)

19. Which of the following is reducing sugar?

Answer: (A)

20. Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : Experimental reaction of CH3Cl with aniline and anhydrous AlCl3 does not give o and p-methylaniline.

Reason (R) : The — NH2 group of aniline becomes deactivating because of salt formation with anhydrous AlCl3 and hence yields m-methyl aniline as the product.

In the light of the above statements, choose the most appropriate answer from the options given below :

(A) Both (A) and (R) are true and (R) is the correct explanation of (A).

(B) Both (A) and (R) are true but (R) is not the correct explanation of (A).

(C) (A) is true, but (R) is false.

(D) (A) is false, but (R) is true.

Answer: (C)

SECTION-B

21. Chlorophyll extracted from the crushed green leaves was dissolved in water to make 2 L solution of Mg of concentration 48 ppm. The number of atoms of Mg in this solution is x × 1020 The value of x is________. (Nearest Integer) (Given : Atomic mass of Mg is 24 g mol–1,  NA = 6.02 × 1023 mol1)

Answer: (24)

22. A mixture of hydrogen and oxygen contains 40% hydrogen by mass when the pressure is 2.2 bar. The partial pressure of hydrogen is _______ bar. (Nearest Integer)

Answer: (2)

23. The wavelength of an electron and a neutron will become equal when the velocity of the electron is x times the velocity of neutron. The value of x is __________. (Nearest Integer)

(Mass of electron is 9.1 × 10–31 kg and mass of neutron is 1.6 × 10–27 kg)

Answer: (1758)

24. 4 g coal is burnt in a bomb calorimeter in excess of oxygen at 298 K and 1 atm pressure.

The temperature of the calorimeter rises from  298 K to 300 K. The enthalpy change during the combustion of coal is – x kJ mol–1. The value of x is___________. (Nearest Integer)

(Given : Heat capacity of bomb calorimeter 20.0 kJ K–1. Assume coal to be pure carbon)

Answer: (200)

25. When 800 mL of 0.5 M nitric acid is heated in a beaker, its volume is reduced to half and 11.5 g of nitric acid is evaporated. The molarity of the remaining nitric acid solution is x × 10–2 (Nearest Integer) (Molar mass of nitric acid is 63 g mol–1)

Answer: (54)

26. At 298 K, the equilibrium constant is 2 × 1015 for the reaction :

Cu(s) + 2Ag+(aq) ⇌ Cu2+(aq) + 2Ag(s)

The equilibrium constant for the reaction

is x × 10–8. The value of x is_______.  (Nearest Integer)

Answer: (2)

27. The amount of charge in F (Faraday) required to obtain one mole of iron from Fe3O4 is _____. (Nearest Integer)

Answer: (8)

28. For a reaction A→ 2B + C the half lives are 100 s and 50 s when the concentration of reactant A is 0.5 and 1.0 mol L–1 The order of the reaction is ________. (Nearest Integer)

Answer: (2)

29. The difference between spin only magnetic moment values of [Co(H2O)6]Cl2 and [Cr(H2O)6]Cl3

Answer: (0)

30. In the presence of sunlight, benzene reacts with Cl2 to give product, X. The number of hydrogens in X is _________.

Answer: (6)

MATHEMATICS

SECTION-A

1. Let f :R→R be a continuous function such that f(3x) – f(x) = x. If f(8) = 7, then f(14) is equal to

(A)  4

(B)  10

(C)  11

(D)  16

Answer: (B)

2. Let O be the origin and A be the point z1 = 1 + 2i. If B is the point z2, Re(z2) < 0, such that OAB is a right angled isosceles triangle with OB as hypotenuse, then which of the following is NOT true?

(A)  arg z2 = π− tan1 3

(B) 

(C)  |z2| = √10

(D)  |2z1 – z2| = 5

Answer: (D)

3. If the system of linear equations.

8x + y + 4z = –2

x + y + z = 0

λx– 3y = μ

has infinitely many solutions, then the distance of the point (λ, μ, −1/2) from the plane 8x + y + 4z + 2 = 0 is :

(A)  3√5

(B)  4

(C)  26/9

(D)  10/3

Answer: (D)

4. Let A be a 2 × 2 matrix with det (A) = –1 and det((A + I) (Adj (A) + I)) = 4. Then the sum of the diagonal elements of A can be

(A)  –1

(B)  2

(C)  1

(D)  –√2

Answer: (B)

5. The odd natural number a, such that the area of the region bounded by y = 1, y = 3, x = 0, x = ya is 364/3, is equal to

(A)  3

(B)  5

(C)  7

(D)  9

Answer: (B)

6. Consider two G.Ps. 2, 22, 23, ….and 4, 42, 43, … of 60 and n terms respectively. If the geometric mean of all the 60 + n terms is (2)225/8, then  is equal to :

(A)  560

(B)  1540

(C)  1330

(D)  2600

Answer: (C)

7. If the function is continuous at x = 0, then k is equal to

(A)  1

(B)  −1

(C)  e

(D)  0

Answer: (A)

8. If 

are continuous on R, then (gof) (2) + (fog) (–2) is equal to

(A)  −10

(B)  10

(C)  8

(D)  −8

Answer: (D)

9. Let 

Then the set of all values of b, for which f(x) has maximum value at x = 1, is :

(A)  (−6, −2)

(B)  (2, 6)

(C)  [−6, −2) ∪ (2, 6]

(D)  [−√6, −2) ∪ (2, √6]

Answer: (C)

10. If  and  then :

Answer: (C)

11. If  then the maximum value of y(x) is

(A)  1/8

(B)  3/4

(C)  1/4

(D)  3/8

Answer: (A)

12. A point P moves so that the sum of squares of its distances from the points (1, 2) and (–2, 1) is 14. Let f(x, y) = 0 be the locus of P, which intersects the x-axis at the points A, B and the y-axis at the points C, D. Then the area of the quadrilateral ACBD is equal to

(A)  9/2

(B)  3√17/2

(C)  3√17/4

(D)  9

Answer: (B)

13. Let the tangent drawn to the parabola y2 = 24x at the point (α, β) is perpendicular to the line 2x + 2y = 5. Then the normal to the hyperbola  at the point (α + 4, β + 4) does NOT pass through the point

(A) (25, 10)

(B) (20, 12)

(C) (30, 8)

(D) (15, 13)

Answer: (D)

14. The length of the perpendicular from the point (1, –2, 5) on the line passing through (1, 2, 4) and parallel to the line x + y – z = 0 = x – 2y + 3z – 5 is

Answer: (A)

15. Let  α > 0. If the projection of  on the vector  is 30, then α is equal to

(A)  15/2

(B)  8

(C)  13/2

(D)  7

Answer: (D)

16. The mean and variance of a binomial distribution are α and α/3, respectively. If P(X = 1) = 4/243 then P(X = 4 or 5) is equal to :

(A)  5/9

(B)  64/81

(C)  16/27

(D)  145/243

Answer: (C)

17. Let E1, E2, E3 be three mutually exclusive events such that  If the maximum and minimum values of p are p1 and p2, then (p1 + p2) is equal to :

(A)  2/3

(B)  5/3

(C)  5/4

(D)  1

Answer: (D)

18. Let  Then  is equal to :

(A)  0

(B)  −2

(C)  −4

(D)  12

Answer: (C)

19. is equal to:

(A)  1

(B)  2

(C)  1/4

(D)  5/4

Answer: (B)

20. The statement (~(p ⇔ ~q)) ⋀ q is :

(A)  a tautology

(B)  a contradiction

(C)  equivalent to (p ⇒ q)⋀ q

(D)  equivalent to (p ⇒ q) ⋀ p

Answer: (D)

SECTION-B

21. If for some p, q, r ∈ R, not all have same sign, one of the roots of the equation (p2 + q2)x2 – 2q(p + r)x + q2 + r2 = 0 is also a root of the equation x2 + 2x – 8 = 0, then  is equal to __________.

Answer: (272)

22. The number of 5-digit natural numbers, such that the product of their digits is 36, is _________.

Answer: (180)

23. The series of positive multiples of 3 is divided into sets: {3}, {6, 9, 12}, {15, 18, 21, 24, 27},…… Then the sum of the elements in the 11th set is equal to ________.

Answer: (6993)

24. The number of distinct real roots of the equation x5(x3 – x2 – x + 1) + x (3x3 – 4x2 – 2x + 4) – 1 = 0 is __________.

Answer: (3)

25. If the coefficients of x and x2 – in the expansion of (1 + x)p (1 – x)q, p, q≤ 15, are – 3 and – 5 respectively, then coefficient of x3 is equal to ______.

Answer: (23)

26. If   then n ∈ N is equal to ________

Answer: (24)

27. Let a curve y = y(x) pass through the point (3, 3) and the area of the region under this curve, above the x-axis and between the abscissae 3 and x (>3) be (y/x)3. If this curve also passes through the point (α, 6√10) in the first quadrant, then α is equal to _______.

Answer: (6)

28. The equations of the sides AB, BC and CA of a triangle ABC are 2x + y = 0, x + py = 15a and x – y = 3, respectively. If its orthocentre is (2, 1),  then p is equal to _______.

Answer: (3)

29. Let the function f(x) = 2x2 – logex, x> 0, be decreasing in (0, a) and increasing in (a, 4). A tangent to the parabola y2 = 4ax at a point P on it passes through the point (8a, 8a –1) but does not pass through the point (−1/a, 0). If the equation of the normal at P is  then α + β is equal to ________.

Answer: (45)

30. Let Q and R be two points on the line  at a distance √26 from the point P(4, 2, 7). Then the square of the area of the triangle PQR is ________.

Answer: (153)

JEE Main Session 1 25th July 2022 Shift 1 Question Paper and Answer Key

JEE Main Session 1 25th July 2022 Shift 1

PHYSICS

Section-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. If momentum [P], area [A] and time [T] are taken as fundamental quantities, then the dimensional formula for the coefficient of viscosity is

(A) [PA–1T0]

(B) [PAT–1]

(C) [PA–1T]

(D) [PA–1T–1]

Answer: (A)

2. Which of the following physical quantities have the same dimensions?

(A) Electric displacement  and surface charge density

(B) Displacement current and electric field

(C) Current density and surface charge density

(D) Electric potential and energy

Answer: (A)

3. A person moved from A to B on a circular path as shown in figure. If the distance travelled by him is 60 m, then the magnitude of displacement would be

(Given cos135°= –0.7)

(A) 42 m

(B) 47 m

(C) 19 m

(D) 40 m

Answer: (B)

4. A body of mass 0.5 kg travels on straight line path with velocity v = (3x2 + 4)m/s. The net workdone by the force during its displacement from x = 0 to x = 2 m is :

(A) 64 J

(B) 60 J

(C) 120 J

(D) 128 J

Answer: (B)

5. A solid cylinder and a solid sphere, having same mass M and radius R, roll down the same inclined plane from top without slipping. They start from rest. The ratio of velocity of the solid cylinder to that of the solid sphere, with which they reach the ground, will be

Answer: (D)

6. Three identical particle A, B and C of mass 100 kg each are placed in a straight line with AB = BC = 13 m. The gravitational force on a fourth particle P of the same mass is F, when placed at a distance 13 m from the particle B on the perpendicular bisector of the line AC. The value of F will be approximately :

(A) 21 G

(B) 100 G

(C) 59 G

(D) 42 G

Answer: (B)

7. A certain amount of gas of volume V at 27°C temperature and pressure 2 × 107 Nm2 expands isothermally until its volume gets doubled. Later it expands adiabatically until its volume gets redoubled. The final pressure of the gas will be

(Use γ = 1.5)

(A) 3.536 × 105 Pa

(B) 3.536 × 106 Pa

(C) 1.25 × 106 Pa

(D) 1.25 × 105 Pa

Answer: (B)

8. Following statements are given:

(1) The average kinetic energy of a gas molecule decreases when the temperature is reduced.

(2) The average kinetic energy of a gas molecule increases with increase in pressure at constant temperature.

(3) The average kinetic energy of a gas molecule decreases with increase in volume.

(4) Pressure of a gas increases with increase in temperature at constant pressure.

(5) The volume of gas decreases with increase in temperature.

Choose the correct answer from the options given below:

(A) (1) & (4) only

(B) (1), (2) & (4) only

(C) (2) & (4) only

(D) (1), (2) & (5) only

Answer: (A)

9. In figure (A), mass ‘2 m’ is fixed on mass ‘m’ which is attached to two springs of spring constant k. In figure (B), mass ‘m’ is attached to two spring of spring constant ‘k’ and ‘2k’. If mass ‘m’ in (A) and (B) are displaced by distance ‘x’ horizontally and then released, then time period T1 and T2 corresponding to (A) and (B) respectively follow the relation.

Answer: (A)

10. A condenser of 2 μF capacitance is charged steadily from 0 to 5C. Which of the following graph represents correctly the variation of potential difference (V) across it’s plates with respect to the charge (Q) on the condenser ?

Answer: (A)

11. Two charged particles, having same kinetic energy, are allowed to pass through a uniform magnetic field perpendicular to the direction of motion. If the ratio of radii of their circular paths is 6 : 5 and their respective masses ratio is 9 : 4. Then, the ratio of their charges will be :

(A) 8 : 5

(B) 5 : 4

(C) 5 : 3

(D) 8 : 7

Answer: (B)

12. To increase the resonant frequency in series LCR circuit,

(A) Source frequency should be increased.

(B) Another resistance should be added in series with the first resistance.

(C) Another capacitor should be added in series with the first capacitor.

(D) The source frequency should be decreased.

Answer: (C)

13. A small square loop of wire of side l is placed inside a large square loop of wire L(L>>l). Both loops are coplanar and their centres coincide at point O as shown in figure. The mutual inductance of the system is :

Answer: (C)

14. The rms value of conduction current in a parallel plate capacitor is 6.9 μA. The capacity of this capacitor, if it is connected to 230 V ac supply with an angular frequency of 600 rad/s, will be :

(A) 5 pF

(B) 50 pF

(C) 100 pF

(D) 200 pF

Answer: (B)

15. Which of the following statement is correct?

(A) In primary rainbow, observer sees red colour on the top and violet on the bottom

(B) In primary rainbow, observer sees violet colour on the top and red on the bottom

(C) In primary rainbow, light wave suffers total internal reflection twice before coming out of water drops

(D) Primary rainbow is less bright than secondary rainbow

Answer: (A)

16. Time taken by light to travel in two different materials A and B of refractive indices μA and μB of same thickness is t1 and t2 If t2 – t1 = 5 × 10–10 s and the ratio of μA to μB is 1 : 2. Then, the thickness of material, in meter is: (Given vA and vB are velocities of light in A and B materials, respectively.)

(A) 5 × 10–10vA m

(B) 5 × 10-10–10 m

(C) 1.5 × 10–10m

(D) 5 × 10–10vB m

Answer: (A)

17. A metal exposed to light of wavelength 800 nm and emits photoelectrons with a certain kinetic energy. The maximum kinetic energy of photo-electron doubles when light of wavelength 500 nm is used. The work function of the metal is:

(Take hc = 1230 eV-nm)

(A) 1.537 eV

(B) 2.46 eV

(C) 0.615 eV

(D) 1.23 eV

Answer: (C)

18. The momentum of an electron revolving in nth orbit is given by: (Symbols have their usual meanings)

(A) nh/2πr

(B) nh/2r

(C) nh/2π

(D) 2πr/nh

Answer: (A)

19. The magnetic moment of an electron (e) revolving in an orbit around nucleus with an orbital angular momentum is given by:

Answer: (B)

20. In the circuit, the logical value of A = 1 or B = 1 when potential at A or B is 5 V and the logical value of A = 0 or B = 0 when potential at A or B is 0 V.

The truth table of the given circuit will be:

Answer: (A)

SECTION-B

21. A car is moving with speed of 150 km/h and after applying the break it will move 27 m before it stops. If the same car is moving with a speed of one third the reported speed then it will stop after travelling ________ m distance.

Answer: (3)

22. For forces are acting at a point P in equilibrium as shown in figure. The ratio of force F1 to F2 is 1 : x where x =_________.

Answer: (3)

23. A wire of length L and radius r is clamped rigidly at one end. When the other end of the wire is pulled by a force F, its length increases by 5 cm. Another wire of the same material of length 4L and radius 4r is pulled by a force 4F under same conditions. The increase in length of this wire is __________ cm.

Answer: (5)

24. A unit scale is to be prepared whose length does not change with temperature and remains 20 cm, using a bimetallic strip made of brass and iron each of different length. The length of both components would change in such a way that difference between their lengths remains constant. If length of brass is 40 cm and length of iron will be ________ cm.

iron= 1.2 × 10−5 K−1 and αbrass = 1.8 × 10−5 K−1)

Answer: (60)

25. An observer is riding on a bicycle and moving towards a hill at 18 kmh–1. He hears a sound from a source at some distance behind him directly as well as after its reflection from the hill. If the original frequency of the sound as emitted by source is 640 Hz and velocity of the sound in air is 320 m/s, the beat frequency between the two sounds heard by observer will be _________ Hz.

Answer: (20)

26. The volume charge density of a sphere of radius 6 m is 2μC cm3. The number of lines of force per unit surface area coming out from the surface of the sphere is _________ × 1010 NC1.

(Given: Permittivity of vacuum = ∈0 = 8.85 × 1012C2N1-m2).

Answer: (45)

27. In the given figure, the value of V0 will be ______ V.

Answer: (4)

28. Eight copper wire of length l and diameter d are joined in parallel to form a single composite conductor of resistance R. If a single copper wire of length 2l have the same resistance (R) then its diameter will be ________ d.

Answer: (4)

29. The energy band gap of semiconducting material to produce violet (wavelength = 4000 Å) LED is _________ eV. (Round off to the nearest integer).

Answer: (3)

30. The required height of a TV tower which can cover the population of 6.03 lakh is h. If the average population density is 100 per square km and the radius of earth is 6400 km, then the value of h will be ________ m.

Answer: (150)

CHEMISTRY

SECTION-A

1. SO2Cl2 on reaction with excess of water results into acidic mixture

SO2Cl2 + 2H2O → H2SO4 + 2HCl

16 moles of NaOH is required for the complete neutralisation of the resultant acidic mixture. The number of moles of SO2Cl2 used is :

(A) 16

(B) 8

(C) 4

(D) 2

Answer: (C)

2. Which of the following sets of quantum numbers is not allowed ?

Answer: (C)

3. The depression in the freezing point observed for a formic acid solution of concentration 0.5 mL L–1 is 0.0405°C. Density of formic acid is 1.05 g mL–1. The Van’t Hoff factor of the formic acid solution is nearly (Given for water kf = 1.86 k kg mol–1)

(A) 0.8

(B) 1.1

(C) 1.9

(D) 2.4

Answer: (C)

4. 20 mL of 0.1 M NH4OH is mixed with 40 mL of 0.05 M HCl. The pH of the mixture is nearest to

(Given :Kb(NH4OH) = 1 × 10–5, log2 = 0.30, log3 = 0.48, log5 = 0.69, log7 = 0.84, log11 = 1.04)

(A) 3.2

(B) 4.2

(C) 5.2

(D) 6.2

Answer: (C)

5. Match List-I with List-II.

Choose the correct answer from the options given below :

(A) (A) – (II), (B) – (IV), (C) – (I), (D) – (III)

(B) (A) – (II), (B) – (I), (C) – (IV), (D) – (III)

(C) (A) – (III), (B) – (IV), (C) – (I), (D) – (II)

(D) (A) – (III), (B) – (I), (C) – (IV), (D) – (II)

Answer: (C)

6. The IUPAC nomenclature of an element with electronic configuration [Rn] 5f146d17s2 is

(A) Unnilbium

(B) Unnilunium

(C) Unnilquadium

(D) Unniltrium

Answer: (D)

7. The compound(s) that is(are) removed as slag during the extraction of copper is

(1) CaO

(2) FeO

(3) Al2O3

(4) ZnO

(5) NiO

Choose the correct answer from the options given below :

(A) (3), (4) only

(B) (1), (2), (5) only

(C) (1), (2) only

(D) (2) only

Answer: (D)

8. The reaction of H2O2 with potassium permanganate in acidic medium leads to the formation of mainly

(A) Mn2+

(B) Mn4+

(C) Mn3+

(D) Mn6+

Answer: (A)

9. Choose the correct order of density of the alkali metals.

(A) Li < K < Na <Rb< Cs

(B) Li < Na < K <Rb< Cs

(C) Cs <Rb< K < Na < Li

(D) Li < Na < K < Cs <Rb

Answer: (A)

10. The geometry around boron in the product ‘B’ formed from the following reaction is

(A) Trigonal planar

(B) Tetrahedral

(C) Pyramidal

(D) Square planar

Answer: (B)

11. The interhalogen compound formed from the reaction of bromine with excess of fluorine is a :

(A) hypohalite

(B) halate

(C) perhalate

(D) halite

Answer: (B)

12. The photochemical smog does not generally contain :

(A) NO

(B) NO2

(C) SO2

(D) HCHO

Answer: (C)

13. A compound ‘A’ on reaction with ‘X’ and ‘Y’ produces the same major product but different by product ‘a’ and ‘b’. Oxidation of ‘a’ gives a substance produced by ants.

‘X’ and ‘Y’ respectively are

(A) KMnO4/H+ and dil. KMnO4, 273 K

(B) KMnO4(dilute), 273 Kand KMnO4/H+

(C) KMnO4/H+ and O3, H2O/Zn

(D) O3, H2O/Zn and KMnO4/H+

Answer: (D)

14. Most stable product of the following reaction is :

Answer: (B)

15. Which one of the following reactions does not represent correct combination of substrate and product under the given conditions?

Answer: (D)

16. An organic compound ‘A’ on reaction with NH3 followed by heating gives compound B. Which on further strong heating gives compound C(C8H5NO2). Compound C on sequential reaction with ethanolic KOH, alkyl chloride and hydrolysis with alkali gives a primary amine. The compound A is :

Answer: (C)

17. Melamine polymer is formed by the condensation of :

Answer: (A)

18. During the denaturation of proteins, which of these structures will remain intact?

(A) Primary

(B) Secondary

(C) Tertiary

(D) Quaternary

Answer: (A)

19. Drugs used to bind to receptors, inhibiting its natural function and blocking a message are called:

(A) Agonists

(B) Antagonists

(C) Allosterists

(D) Anti histaminists

Answer: (B)

20. Given below are two statements:

Statement I: On heating with KHSO4, glycerol is dehydrated and acrolein is formed.

Statement II:Acrolein has fruity odour and can be used to test glycerol’s presence.

Choose the correct option.

(A) Both Statement I and Statement II are correct.

(B) Both Statement I and Statement II are incorrect.

(C) Statement I is correct but Statement II is incorrect.

(D) Statement I is incorrect but Statement II is correct.

Answer: (C)

SECTION-B

21. Among the following species

the number of species showing diamagnetism is ________.

Answer: (2)

22. The enthalpy of combustion of propane, graphite and dihydrogen at 298 K are –2220.0 kJ mol–1, –393.5 kJ mol–1 and –285.8 kJ mol–1, respectively. The magnitude of enthalpy of formation of propane (C3H8) is _____ kJ mol–1. (Nearest integer)

Answer: (104)

23. The pressure of a moist gas at 27°C is 4 atm. The volume of the container is doubled at the same temperature. The new pressure of the moist gas is ______ ×10–1 (Nearest integer)

(Given: The vapour pressure of water at 27°C is 0.4 atm.)

Answer: ()

24. The cell potential for Zn|Zn2+(aq)||Snx+|Sn is 0.801 V at 298 K. The reaction quotient for the above reaction is 10–2. The number of electrons involved in the given electrochemical cell reaction is ________.

(Given  and 

Answer: (4)

25. The half-life for the decomposition of gaseous compound A is 240 s when the gaseous pressure was 500 torr initially. When the pressure was 250 torr, the half-life was found to be 4.0 min. The order of the reaction is ______. (Nearest integer)

Answer: (1)

26. Consider the following metal complexes:

[Co(NH3)6]3+

[CoCl(NH3)5]2+

[Co(CN)6]3–

[Co(NH3)5(H2O)]3+

The spin-only magnetic moment value of the complex that absorbs light with shortest wavelength is _______ B.M. (Nearest integer)

Answer: (0)

27. Among Co3+, Ti2+, V2+ and Cr2+ ions, one if used as a reagent cannot liberate H2 from dilute mineral acid solution, its spin-only magnetic moment in gaseous state is________ B.M. (Nearest integer)

Answer: (5)

28. While estimating the nitrogen present in an organic compound by Kjeldahl’s method, the ammonia evolved from 0.25 g of the compound neutralized 2.5 mL of 2 M H2SO4. The percentage of nitrogen present in organic compound is ________.

Answer: (56)

29. The number of sp3 hybridised carbons in an acyclic neutral compound with molecular formula C4H5N is ________.

Answer: (1)

30. In the given reaction,

(where Et is –C2H5)

The number of chiral carbon(s) in product A is _________.

Answer: (2)

MATHEMATICS

SECTION-A

1. The total number of functions, f : {1, 2, 3, 4} ● {1, 2, 3, 4, 5, 6} such that f(1) + f(2) = f(3), is equal to

(A) 60

(B) 90

(C) 108

(D) 126

Answer: (B)

2. If α, β, γ, δ are the roots of the equation x4 + x3 + x2 + x + 1 = 0, then α2021 + β2021 + γ2021 + δ2021 is equal to

(A) −4

(B) −1

(C) 1

(D) 4

Answer: (B)

3. For n ∈ N, let  and  Then the number of elements in the set {n ∈ N : Sn∩Tn = ϕ} is :

(A) 0

(B) 2

(C) 3

(D) 4

Answer: (D)

4. The number of q∈ (0, 4π) for which the system of linear equations

3(sin 3θ) x – y + z = 2

3(cos 2θ) x + 4y + 3z = 3

6x + 7y + 7z = 9

has no solution, is

(A) 6

(B) 7

(C) 8

(D) 9

Answer: (B)

5. If  then 8(α + β) is equal to :

(A) 4

(B) −8

(C) −4

(D) 8

Answer: (C)

6. If the absolute maximum value of the function in the interval [−3, 0] is f(α), then:

(A) α = 0

(B) α = −3

(C) α∈ (−1, 0)

(D) α∈ (−3, −1)

Answer: (B)

7. The curve y(x) = ax3 + bx2 + cx + 5 touches the x-axis at the point P(–2, 0) and cuts the y-axis at the point Q, where y′ is equal to 3. Then the local maximum value of y(x) is

(A) 27/4

(B) 29/4

(C) 37/4

(D) 9/2

Answer: (A)

8. The area of the region given by A = {(x, y); x2≤ y ≤ min{x + 2, 4 – 3x}} is

(A) 31/8

(B) 17/6

(C) 19/6

(D) 27/8

Answer: (B)

9. For any real number x, let [x] denote the largest integer less than equal to x. Let f be a real valued function defined on the interval [–10, 10] by . Then the value of  is:

(A) 4

(B) 2

(C) 1

(D) 0

Answer: (A)

10. The slope of the tangent to a curve C : y = y(x) at any point (x, y) on it is  If C passes through the points  then eα is equal to:

Answer: (B)

11. The general solution of the differential equation (x – y2)dx + y(5x + y2)dy = 0 is :

(A) (y2 + x)4 = C|(y2 + 2x)3|

(B) (y2 + 2x)4 = C|(y2 + 2x)3|

(C) |(y2 + x)3| = C(2y2 + x)4

(D) |(y2 + 2x)3| = C(2y2 + x)4

Answer: (A)

12. A line, with the slope greater than one, passes through the point A(4, 3) and intersects the line

x – y – 2 = 0 at the point B. If the length of the line segment AB is√29/3, then B also lies on the line:

(A) 2x + y = 9

(B) 3x – 2y = 7

(C) x + 2y = 6

(D) 2x – 3y = 3

Answer: (C)

13. Let the locus of the centre (α, β), β > 0, of the circle which touches the circle x2 +(y – 1)2 = 1 externally and also touches the x-axis be L. Then the area bounded by L and the line y = 4 is :

(A) 32√2/3

(B) 40√2/3

(C) 64/3

(D) 32/3

Answer: (C)

14. Let P be the plane containing the straight line  and perpendicular to the plane containing the straight lines  If d is the distance P from the point (2, –5, 11), then d2 is equal to :

(A) 147/2

(B) 96

(C) 32/3

(D) 54

Answer: (D)

15. Let ABC be a triangle 

(A) Both (S1) and (S2) are true

(B) Only (S1) is true

(C) Only (S2) is true

(D) Both (S1) and (S2) are false

Answer: (D)

16. If the sum and the product of mean and variance of a binomial distribution are 24 and 128 respectively, then the probability of one or two successes is :

(A) 33/232

(B) 33/229

(C) 33/228

(D) 33/227

Answer: (C)

17. If the numbers appeared on the two throws of a fair six faced die are α and β, then the probability that x2 + αx + β > 0, for all x ∈ R, is :

(A) 17/36

(B) 4/9

(C) 1/2

(D) 19/36

Answer: (A)

18. The number of solutions of |cos x| = sinx, such that –4π ≤ x ≤ 4π is :

(A) 4

(B) 6

(C) 8

(D) 12

Answer: (C)

19. A tower PQ stands on a horizontal ground with base Q on the ground. The point R divides the tower in two parts such that QR = 15 m. If from a point A on the ground the angle of elevation of R is 60° and the part PR of the tower subtends an angle of 15° at A, then the height of the tower is :

(A) 5(2√3 + 3) m

(B) 5(√3 + 3)m

(C) 10(√3 + 1) m

(D) 10(2√3 + 1) m

Answer: (A)

20. Which of the following statements is a tautology?

(A) ((~p) ∨ q) ⇒ p

(B) p⇒ ((~p) ∨ q)

(C) ((~p) ∨ q) ⇒ q

(D) q⇒ ((~p) ∨ q)

Answer: (D)

SECTION-B

21. Let  and B = A – I. If

then the number of elements in the set {n ∈ {1, 2, …, 1000} : An + (ωB)n = A + B} is equal to _________.

Answer: (17)

22. The letters of the work ‘MANKIND’ are written in all possible orders and arranged in serial order as in an English dictionary. Then the serial number of the word ‘MANKIND’ is ______.

Answer: (1492)

23. If the maximum value of the term independent of t in the expansion of  is K, then 8K is equal to _________.

Answer: (6006)

24. Let a, b be two non-zero real numbers. If p and r are the roots of the equation x2 – 8ax + 2a = 0 and q and s are the roots of the equation x2 + 12bx + 6b = 0, such that  are in A.P., then a1 – b1 is equal to _________.

Answer: (38)

25. Let a1 = b1 = 1, an = an – 1 + 2 and bn = an + bn – 1 for every natural number n ≥ 2. Then  is equal to _________.

Answer: (27560)

26. Let  where [α] denotes the greatest integer less than or equal to α. Then the number of points in R where f is not differentiable is _________.

Answer: (3)

27. If   then the integral value of k is equal to _______.

Answer: (5)

28. Let the equation of two diameters of a circle x2 + y2 – 2x + 2fy + 1 = 0 be 2px – y = 1 and 2x + py = 4p. Then the slope m ∈ (0, ∞) of the tangent to the hyperbola 3x2 – y2 = 3 passing through the centre of the circle is equal to _______.

Answer: (2)

29. The sum of diameters of the circles that touch (i) the parabola 75x2 = 64(5y – 3) at the point (8/5, 6/5) and (ii) the y-axis is equal to _______.

Answer: (10)

30. The line of shortest distance between the lines  and  makes angle of  with the plane P :ax – y – z = 0, (a > 0). If the image of the point (1, 1, –5) in the plane P is (α, β, γ), then α + β – γ is equal to ________.

Answer: (3)

JEE Main Session 1 29th June 2022 Shift-1 Question Paper and Answer Key

JEE Main Session 1 29th June 2022 Shift 1

PHYSICS

SECTION-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii)   Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. Two balls A and B are placed at the top of 180 m tall tower. Ball A is released from the top at t = 0 s. Ball B is thrown vertically down with an initial velocity u at t = 2 s. After a certain time, both balls meet 100 m above the ground. Find the value of u in ms–1 [use g = 10 ms–2]

(A)  10

(B)  15

(C)  20

(D)  30

Answer: (D)

2. A body of mass M at rest explodes into three pieces, in the ratio of masses 1 : 1 : 2. Two smaller pieces fly off perpendicular to each other with velocities of 30 ms–1 and 40 ms–1 respectively. The velocity of the third piece will be

(A)  15 ms1

(B)  25ms1

(C)  35ms1

(D)  50ms1

Answer: (B)

3. The activity of a radioactive material is 2.56 × 10–3 If the half life of the material is 5 days, after how many days the activity will become 2 × 10–5Ci?

(A)  30 days

(B)  35days

(C)  40days

(D)  25days

Answer: (B)

4. A spherical shell of 1 kg mass and radius R is rolling with angular speed ω on horizontal plane (as shown in figure). The magnitude of angular momentum of the shell about the origin O is  The value of a will be

(A)  2

(B)  3

(C)  4

(D)  5

Answer: (C)

5. A cylinder of fixed capacity of 44.8 litres contains helium gas at standard temperature and pressure. The amount of heat needed to raise the temperature of gas in the cylinder by 20.0°C will be

(Given gas constant R = 8.3 JK–1-mol–1)

(A)  249 J

(B)  415 J

(C)  498 J

(D)  830 J

Answer: (C)

6. A wire of length L is hanging from a fixed support. The length changes to L1 and L2 when masses 1 kg and 2 kg are suspended, respectively, from its free end. Then the value of L is equal to

(A) 

(B) 

(C)  2L1 – L2

(D)  3L1 – 2L2

Answer: (C)

7. Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : The photoelectric effect does not takes place, if the energy of the incident radiation is less than the work function of a metal.

Reason R:Kinetic energy of the photoelectrons is zero, if the energy of the incident radiation is equal to the work function of a metal.

In the light of the above statements, choose the most appropriate answer from the options given below.

(A) Both A and R are correct and R is the correct explanation of A

(B) Both A and R are correct but R is not the correct explanation of A

(C) A is correct but R is not correct

(D) A is not correct but R is correct

Answer: (B)

8. A particle of mass 500 gm is moving in a straight line with velocity v = bx5/2. The work done by the net force during its displacement from x = 0 to x = 4 m is : (Take b = 0.25 m–3/2s–1).

(A)  2 J

(B)  4 J

(C)  8 J

(D)  16 J

Answer: (D)

9. A charge particle moves along circular path in a uniform magnetic field in a cyclotron. The kinetic energy of the charge particle increases to 4 times its initial value. What will be the ratio of new radius to the original radius of circular path of the charge particle

(A)  1 : 1

(B)  1 : 2

(C)  2 : 1

(D)  1 : 4

Answer: (C)

10. For a series LCR circuit, I vs ω curve is shown :

(a) To the left of ωr, the circuit is mainly capacitive.

(b) To the left of ωr, the circuit is mainly inductive.

(c) At ωr, impedance of the circuit is equal to the resistance of the circuit.

(d) At ωr, impedance of the circuit is 0.

Choose the most appropriate answer from the options given below.

(A) (a) and (d) only

(B) (b) and (d) only

(C) (a) and (c) only

(D) (b) and (c) only

Answer: (C)

11. A block of metal weighing 2 kg is resting on a frictionless plane (as shown in figure). It is struck by a jet releasing water at a rate of 1 kgs–1 and at a speed of 10 ms–1. Then, the initial acceleration of the block, in ms–2, will be:

(A)  3

(B)  6

(C)  5

(D)  4

Answer: ()

12. In van der Wall equation  P is pressure, V is volume, R is universal gas constant and T is temperature The ratio of constants a/b is dimensionally equal to:

(A)  P/V

(B)  V/P

(C)  PV

(D)  PV3

Answer: (C)

13. Two vectors  have equal magnitudes. If magnitude of   is equal to two times the magnitude of  , then the angle between  will be:

(A)  sin1(3/5)

(B)  sin1(1/3)

(C)  cos1(3/5)

(D)  cos1(1/3)

Answer: (C)

14. The escape velocity of a body on a planet ‘A’ is 12 kms–1. The escape velocity of the body on another planet ‘B’, whose density is four times and radius is half of the planet ‘A’, is:

(A)  12 kms1

(B)  24kms1

(C)  36kms1

(D)  6kms1

Answer: (A)

15. At a certain place the angle of dip is 30° and the horizontal component of earth’s magnetic field is 0.5 G. The earth’s total magnetic field (in G), at that certain place, is :

(A)  1/√3

(B)  1/2

(C)  √3

(D)  1

Answer: (A)

16. A longitudinal wave is represented by  The maximum particle velocity will be four times the wave velocity if the determined value of wavelength is equal to :

(A)  2π

(B)  5π

(C)  π

(D)  5π/2

Answer: (B)

17. A parallel plate capacitor filled with a medium of dielectric constant 10, is connected across a battery and is charged. The dielectric slab is replaced by another slab of dielectric constant 15. Then the energy of capacitor will :

(A) increased by 50%

(B) decrease by 15%

(C) increase by 25%

(D) increase by 33%

Answer: (A)

18. A positive charge particle of 100 mg is thrown in opposite direction to a uniform electric field of strength 1 × 105 NC–1. If the charge on the particle is 40 μC and the initial velocity is 200 ms–1, how much distance it will travel before coming to the rest momentarily?

(A)  1 m

(B)  5 m

(C)  10 m

(D)  0.5 m

Answer: (D)

19. Using Young’s double slit experiment, a monochromatic light of wavelength 5000 Å produces fringes of fringe width 0.5 mm. If another monochromatic light of wavelength 6000 Å is used and the separation between the slits is doubled, then the new fringe width will be :

(A)  0.5 mm

(B)  1.0mm

(C)  0.6mm

(D)  0.3mm

Answer: (D)

20. Only 2% of the optical source frequency is the available channel bandwidth for an optical communicating system operating at 1000 nm. If an audio signal requires a bandwidth of 8 kHz, how many channels can be accommodated for transmission?

(A) 375 × 107

(B) 75 × 107

(C) 375 × 108

(D) 75 × 109

Answer: (B)

SECTION-B

21. Two coils require 20 minutes and 60 minutes respectively to produce same amount of heat energy when connected separately to the same source. If they are connected in parallel arrangement to the same source; the time required to produce same amount of heat by the combination of coils, will be _______ min.

Answer: (15)

22. The intensity of the light from a bulb incident on a surface is 0.22 W/m2. The amplitude of the magnetic field in this light-wave is ______ × 10–9

(Given : Permittivity of vacuum ε0 = 8.85 × 10–12C2N–1–m–2, speed of light in vacuum c = 3 × 108 ms–1)

Answer: (43)

23. As per the given figure, two plates A and B of thermal conductivity K and 2 K are joined together to form a compound plate. The thickness of plates are 4.0 cm and 2.5 cm, respectively and the area of cross-section is 120 cm2 for each plate. The equivalent thermal conductivity of the compound plate is  then the value of α will be ________.

Answer: (21)

24. A body is performing simple harmonic with an amplitude of 10 cm. The velocity of the body was tripled by air Jet when it is at 5 cm from its mean position. The new amplitude of vibration is √x cm. The value of x is _______.

Answer: (700)

25. The variation of applied potential and current flowing through a given wire is shown in figure. The length of wire is 31.4 cm. The diameter of wire is measured as 2.4 cm. The resistivity of the given wire is measured as x × 10–3Ω cm. The value of x is ________.

[Take π = 3.14]

Answer: (144)

26. 300 cal. of heat is given to a heat engine and it rejects 225 cal. of heat. If source temperature is 227°C, then the temperature of sink will be _______°C.

Answer: (102)

27. √d1 and √d2 are the impact parameters corresponding to scattering angles 60° and 90° respectively, when an α particle is approaching a gold nucleus. For d1 = xd2, the value of x will be _________.

Answer: (3)

28. A transistor is used in an amplifier circuit in common emitter mode. If the base current changes by 100μA, it brings a change of 10mA in collector current. If the load resistance is 2kΩ and input resistance is 1kΩ, the value of power gain is x×104. The value of x is _______.

Answer: (2)

29. A parallel beam of light is allowed to fall on a transparent spherical globe of diameter 30 cm and refractive index 1.5. The distance from the centre of the globe at which the beam of light can converge is ________ mm.

Answer: (225)

30. For the network shown below, the value of VB– VA is ________V.

Answer: (10)

CHEMISTRY

SECTION-A

1. Production of iron in blast furnace follows the following equation Fe3O4(s) + 4CO(g) → 3Fe(l) + 4CO2(g) when 4.640 kg of Fe3O4 and 2.520 kg of CO are allowed to react then the amount of iron (in g) produced is :

[Given : Molar Atomic mass (g mol–1): Fe = 56 Molar Atomic mass (g mol–1) : 0 = 16  Molar Atomic mass (g mol–1): = C = 12

(A)  1400

(B)  2200

(C)  3360

(D)  4200

Answer: (C)

2. Which of the following statements are correct ?

(A) The electronic configuration of Cr is [Ar] 3d5 4s1.

(B) The magnetic quantum number may have a negative value.

(C) In the ground state of an atom, the orbitals are filled in order of their increasing energies.  (D) The total number of nodes are given by n – 2.

Choose the most appropriate answer from the options given below :

(A) (A), (C) and (D) only

(B) (A) and (B) only

(C) (A) and (C) only

(D) (A), (B) and (C) only

Answer: (D)

3. Arrange the following in the decreasing order of their covalent character :

(A) LiCl

(B) NaCl

(C) KCl

(D) CsCl

Choose the most appropriate answer from the options given below :

(A) (A) > (C) > (B) > (D)

(B) (B) > (A) > (C) > (D)

(C) (A) > (B) > (C) > (D)

(D) (A) > (B) > (D) > (C)

Answer: (C)

4. The solubility of AgCl will be maximum in which of the following?

(A) 0.01 M KCl

(B) 0.01 M HCl

(C) 0.01 M AgNO3

(D) Deionised water

Answer: (D)

5. Which of the following is a correct statement?

(A) Brownian motion destabilises sols.

(B) Any amount of dispersed phase can be added to emulsion without destabilising it.

(C) Mixing two oppositely charged sols in equal amount neutralises charges and stabilises colloids.

(D) Presence of equal and similar charges on colloidal particles provides stability to the colloidal solution.

Answer: (D)

6. The electronic configuration of Pt(atomic number 78) is:

(A) [Xe] 4f14 5d9 6s1

(B) [Kr] 4f14 5d10

(C) [Xe] 4f14 5d10

(D) [Xe] 4f14 5d8 6s2

Answer: (A)

7. In isolation of which one of the following metals from their ores, the use of cyanide salt is not commonly involved?

(A) Zinc

(B) Gold

(C) Silver

(D) Copper

Answer: (D)

8. Which one of the following reactions indicates the reducing ability of hydrogen peroxide in basic medium?

(A)  HOCl + H2O2→ H3O+ + Cl + O2

(B)  PbS + 4H2O2→ PbSO4 + 4H2O

(C)  2MnO4 + 3H2O2→ 2MnO2 + 3O2 + 2H2O + 2OH

(D)  Mn2++  H2O2→ Mn4+ + 2OH

Answer: (C)

9. Match the List-I with List- II.

Choose the most appropriate answer from the options given below:

(A) (A)-(I), (B)-(II), (C)-(III), (D)-(IV)

(B) (A)-(III), (B)-(II), (C)-(I), (D)-(IV)

(C) (A)-(III), (B)-(I), (C)-(II), (D)-(IV)

(D) (A)-(IV), (B)-(II), (C)-(I), (D)-(III)

Answer: (A)

10. Match the List-I with List- II.

Choose the most appropriate answer from the option given below:

(A) (A)-(III), (B)-(I), (C)-(IV), (D)-(II)

(B) (A)-(IV), (B)-(III), (C)-(II), (D)-(I)

(C) (A)-(II), (B)-(III), (C)-(IV), (D)-(I)

(D) (A)-(I), (B)-(IV), (C)-(II), (D)-(III)

Answer: (A)

11. The oxoacid of phosphorus that is easily obtained from a reaction of alkali and white phosphorus and has two P-H bonds, is:

(A) Phosphonic acid

(B) Phosphinic acid

(C) Pyrophosphorus acid

(D) Hypophosphoric acid

Answer: (B)

12. The acid that is believed to be mainly responsible for the damage of TajMahal is

(A) sulfuric acid

(B) hydrofluoric acid

(C) phosphoric acid

(D) hydrochloric acid

Answer: (A)

13. Two isomers ‘A’ and ‘B’ with molecular formula C4H8 give different products on oxidation with KMnO4/H+ results in effervescence of a gas and gives ketone. The compound ‘A’ is

Answer: (D)

14. 

In the given conversion the compound A is:

Answer: (B)

15. Given below are two statements :

Statement I : The esterification of carboxylic acid with an alcohol is a nucleophilic acyl substitution.

Statement II : Electron withdrawing groups in the carboxylic acid will increase the rate of esterification reaction.

Choose the most appropriate option :

(A) Both Statement I and Statement II are correct.

(B) Both Statement I and Statement II are incorrect.

(C) Statement I is correct but Statement II is incorrect.

(D) Statement I is incorrect but Statement II is correct.

Answer: (A)

16. 

Consider the above reactions, the product A and product B, respectively are

Answer: (C)

17. The polymer, which can be stretched and retains its original status on releasing the force is

(A) Bakelite

(B) Nylon 6, 6

(C) Buna-N

(D) Terylene

Answer: (C)

18. Sugar moiety in DNA and RNA molecules, respectively are

(A) β-D-2-deoxyribose, β-D-deoxyribose

(B) β-D-2-deoxyribose, β-D-ribose

(C) β-D-ribose, β-D-2-deoxyribose

(D) β-D-deoxyribose, β-D-2-deoxyribose

Answer: (B)

19. Which of the following compound does not contain sulphur atom?

(A) Cimetidine

(B) Ranitidine

(C) Histamine

(D) Saccharin

Answer: (C)

20. Given below are two statements.

Statement I : Phenols are weakly acidic.

Statement II : Therefore they are freely soluble in NaOH solution and are weaker acids than alcohols and water.

Choose the most appropriate option.

(A) Both Statement I and Statement II are correct.

(B) Both Statement I and Statement II are correct.

(C) Statement I is correct but Statement II is incorrect.

(D) Statement I is incorrect but Statement II is correct.

Answer: (C)

SECTION-B

21. Geraniol, a volatile organic compound, is a component of rose oil. The density of the vapour is 0.46 gL–1 at 257°C and 100 mm Hg. The molar mass of geraniol is ______ g mol–1. (Nearest Integer) [Given: R = 0.082 L atm K–1mol–1]

Answer: (152)

22. 17.0 g of NH3 completely vapourises at – 33.42°C and 1 bar pressure and the enthalpy change in the process is 23.4 kJ mol–1. The enthalpy change for the vapourisation of 85 g of NH3 under the same conditions is ________ kJ.

Answer: (117)

23. 1.2 mL of acetic acid is dissolved in water to make 2.0 L of solution. The depression in freezing point observed for this strength of acid is 0.0198°C. The percentage of dissociation of the acid is ____ . (Nearest integer)

[Given: Density of acetic acid is 1.02 g mL–1

Molar mass of acetic acid is 60 g mol–1

Kf(H2O) = 1.85 K kg mol–1]

Answer: (5)

24. A dilute solution of sulphuric acid is electrolysed using a current of 0.10 A for 2 hours to produce hydrogen and oxygen gas. The total volume of gases produced at STP is ______ cm3. (Nearest integer)

[Given : Faraday constant F = 96500 C mol–1 at STP, molar volume of an ideal gas is 22.7 L mol–1]

Answer: (127)

25. The activation energy of one of the reactions in a biochemical process is 532611 J mol–1. When the temperature falls from 310 K to 300 K, the change in rate constant observed is k300 = x × 10–3 k310. The value of x is _________.

[Given: ln10 = 2.3, R = 8.3 JK–1mol–1]

Answer: (1)

26. The number of terminal oxygen atoms present in the product B obtained from the following reaction is ________.

FeCr2O4 + Na2CO3 + O2 → A + Fe2O3 + CO2

A + H+ → B + H2O + Na+

Answer: (6)

27. An acidified manganate solution undergoes disproportionation reaction. The spin-only magnetic moment value of the product having manganese in higher oxidation state is _______ B.M. (Nearest integer)

Answer: (0)

28. Kjeldahl’s method was used for the estimation of nitrogen in an organic compound. The ammonia evolved from 0.55 g of the compound neutralised 12.5 mL of 1 M H2SO4 The percentage of nitrogen in the compound is ________. (Nearest integer)

Answer: (64)

29. Observe structures of the following compounds

The total number of structures/compounds which possess asymmetric carbon atoms is _______.

Answer: (3)

30. 

The number of carbon atoms present in the product B is __________.

Answer: (1)

MATHEMATICS

SECTION-A

1. The probability that a randomly chosen 2 × 2 matrix with all the entries from the set of first 10 primes, is singular, is equal to :

(A)  133/104

(B)  18/103

(C)  19/103

(D)  271/104

Answer: (C)

2. Let the solution curve of the differential equation  y(1) = 3 be y = y(x).

Then y(2) is equal to :

(A)  15

(B)  11

(C)  13

(D)  17

Answer: (A)

3. If the mirror image of the point (2, 4, 7) in the plane 3x – y + 4z = 2 is (a, b, c), then 2a + b + 2c is equal to:

(A)  54

(B)  50

(C)  –60

(D)  –42

Answer: (C)

4. Let f : R ⇒ R be a function defined by :

where [t] is the greatest integer less than or equal to t. Let m be the number of points where f is not differentiable and  Then the ordered pair (m, I) is equal to :

(A)  (3, 27/4)

(B)  (3, 23/4)

(C)  (4, 27/4)

(D)  (4, 23/4)

Answer: (C)

5. Let  and  where α, β∈ R, be three vectors. If the projection of  is 10/3 and  then the value of α + β equal to :

(A)  3

(B)  4

(C)  5

(D)  6

Answer: (A)

6. The area enclosed by y2 = 8x and y = √2x that lies outside the triangle formed by y = √2x, x = 1, y = 2√2 is equal to:

(A)  16√2/6

(B)  11√2/6

(C)  13√2/6

(D)  5√2/6

Answer: (C)

7. If the system of linear equations

2x + y – z = 7

x – 3y + 2z = 1

x + 4y + δz = k, where δ, k ∈ R

has infinitely many solutions, then δ + k is equal to:

(A)  –3

(B)  3

(C)  6

(D)  9

Answer: (B)

8. Let α and β be the roots of the equation x2 + (2i – 1) = 0. Then, the value of |α2 + β2| is equal to:

(A)  50

(B)  250

(C)  1250

(D)  1500

Answer: (A)

9. Let ∆ ∈ {⋀, ⋁, ⇒, ⇔}be such that (p ⋀ q) ∆ ((p ⋁ q) ⇒ q) is a tautology. Then ∆ is equal to :

(A)  ⋀

(B)  ⋁

(C)  ⇒

(D)  ⇔

Answer: (C)

10. Let A = [aij] be a square matrix of order 3 such that aij = 2j–i, for all i, j = 1, 2, 3. Then, the matrix A2 + A3 + … + A10 is equal to :

Answer: (A)

11. Let a set A = A1⋃ A2⋃ …⋃Ak, where Ai⋂Aj = Φ for i ≠ j, 1 ≤ i, j ≤ k. Define the relation R from A to A by R = {(x, y) : y ∈ Ai if and only if x ∈ Ai, 1 ≤ i ≤ k}. Then, R is :

(A) reflexive, symmetric but not transitive

(B) reflexive, transitive but not symmetric

(C) reflexive but not symmetric and transitive

(D) an equivalence relation

Answer: (D)

12. Let  be a sequence such that a0 = a1 = 0 and an+2 = 2an+1 – an + 1 for all n ≥ Then,  is equal to

(A)  6/343

(B)  7/216

(C)  8/343

(D)  49/216

Answer: (B)

13. The distance between the two points A and A′ which lie on y = 2 such that both the line segments AB and A′B (where B is the point (2, 3)) subtend angle π/4 at the origin, is equal to

(A)  10

(B)  48/5

(C)  52/5

(D)  3

Answer: (C)

14. A wire of length 22 m is to be cut into two pieces. One of the pieces is to be made into a square and the other into an equilateral triangle. Then, the length of the side of the equilateral triangle, so that the combined area of the square and the equilateral triangle is minimum, is

Answer: (B)

15. The domain of the function  is :

Answer: (D)

16. If the constant term in the expansion of  is 2kl, where l is an odd integer, then the value of k is equal to

(A)  6

(B)  7

(C)  8

(D)  9

Answer: (D)

17. , where [t] denotes greatest integer less than or equal to t, is equal to

(A)  –3

(B)  –2

(C)  2

(D)  0

Answer: (D)

18. Let PQ be a focal chord of the parabola y2 = 4x such that it subtends an angle of π/2 at the point (3, 0). Let the line segment PQ be also a focal chord of the ellipse  If e is the eccentricity of the ellipse E, then the value of 1/e2 is equal to

(A) 1 + √2

(B) 3 + 2√2

(C) 1 + 2√3

(D) 4 + 5√3

Answer: (B)

19. Let the tangent to the circle C1: x2 + y2 = 2 at the point M(–1, 1) intersect the circle C2: (x – 3)2 + (y – 2)2 = 5, at two distinct points A and B. If the tangents to C2 at the points A and B intersect at N, then the area of the triangle ANB is equal to

(A)  1/2

(B)  2/3

(C)  1/6

(D)  5/3

Answer: (C)

20. Let the mean and the variance of 5 observations x1, x2, x3, x4, x5 be 24/5 and 194/25, respectively. If the mean and variance of the first 4 observations are 7/2 and a, respectively, then (4a + x5) is equal to

(A)  13

(B)  15

(C)  17

(D)  18

Answer: (B)

SECTION-B

21. Let S = {z ∈C : |z – 2| ≤ 1, z(1 + i) +  Let |z – 4i| attains minimum and maximum values, respectively, at z1∈ S and z2 ∈ If 5(|z1|2 + |z2|2) = α + β√5 where α and β are integers, then the value of α + β is equal to _________.

Answer: (26)

22. Let y = y(x) be the solution of the differential equation  If  then the value of 3α2 is equal to ______.

Answer: (2)

23. Let d be the distance between the foot of perpendiculars of the point P(1, 2, –1) and Q(2, –1, 3) on the plane –x + y + z = 1. Then d2 is equal to ________.

Answer: (26)

24. The number of elements in the set S = {θ∈ [−4π, 4π] : 3 cos2 2θ + 6 cos 2θ – 10 cos2θ + 5 = 0} is _________.

Answer: (32)

25. The number of solutions of the equation 2θ– cos2θ + √2 = 0 in R is equal to ___________.

Answer: (1)

26.  is equal to _________.

Answer: (29)

27. Let c, k ∈ If f(x) = (c + 1)x2 + (1 – c2)x + 2k and f(x + y) = f(x) + f(y) – xy, for all x, y ∈ R, then the value of |2(f(1) + f(2) + f(3) + … + f(20))| is equal to _________.

Answer: (3395)

28. Let  a > 0, b > 0, be a hyperbola such that the sum of lengths of the transverse and the conjugate axes is 4(2√2 + √14). If the eccentricity H is √11/2, then the value of a2 + b2 is equal to ____________.

Answer: (88)

29. be a plane. Let P2 be another plane which passes through the points (2, –3, 2), (2, –2, –3) and (1, –4, 2). If the direction ratios of the line of intersection of P1 and P2 be 16, α, β, then the value of α + β is equal to _______.

Answer: (28)

30. Let b1b2b3b4 be a 4-element permutation with bi{1, 2, 3,…..,100} for 1 ≤ i ≤ 4 and bi ≠ bj for i ≠ j, such that either b1, b2, b3 are consecutive integers or b2, b3, b4 are consecutive integers. Then the number of such permutations b1b2b3b4 is equal to _______.

Answer: (18915)

JEE Main Session 1 28th June 2022 Shift-1 Question Paper and Answer Key

JEE Main Session 1 28th June 2022 Shift 1

PHYSICS

Section-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii)   Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : Product of Pressure (P) and time (t) has the same dimension as that of coefficient of viscosity.

Reason R : Coefficient of viscosity 

Choose the correct answer from the options given below.

(A) Both A and R true, and R is correct explanation of A.

(B) Both A and R are true but R is NOT the correct explanation of A.

(C) A is true but R is false.

(D) A is false but R is true.

Answer: (C)

2. A particle of mass m is moving in a circular path of constant radius r such that its centripetal acceleration (a) is varying with time t as a = k2rt2, where k is a constant. The power delivered to the particle by the force acting on it is given as

(A) Zero

(B) mk2r2t2

(C) mk2r2t

(D) mk2rt

Answer: (C)

3. Motion of a particle in x-y plane is described by a set of following equations  and y = 4sin(ωt) m. The path of the particle will be

(A) Circular

(B) Helical

(C) Parabolic

(D) Elliptical

Answer: (A)

4. Match List-I with List-II

Choose the correct answer from the options given below.

(A) A-II, B-I, C-IV, D-III

(B) A-I, B-II, C-IV, D-III

(C) A-II, B-I, C-III, D-IV

(D) A-I, B-II, C-III, D-IV

Answer: (A)

5. Two planets A and B of equal mass are having their period of revolutions TA and TB such that TA= 2TB. These planets are revolving in the circular orbits of radii rA and rB Which out of the following would be the correct relationship of their orbits?

Answer: (C)

6. A water drop of diameter 2 cm is broken into 64 equal droplets. The surface tension of water is 0.075 N/m. In this process the gain in surface energy will be

(A) 2.8 × 10–4 J

(B) 1.5 × 10–3 J

(C) 1.9 × 10–4 J

(D) 9.4 × 10–5 J

Answer: (A)

7. Given below are two statements

Statement-I: When μ amount of an ideal gas undergoes adiabatic change from state (P1, V1, T1) to state (P2, V2, T2), then work done is  and R = universal gas constant.

Statement-II: In the above case, when work is done on the gas, the temperature of the gas would rise.

Choose the correct answer from the options given below.

(A) Both statement-I and statement-II are true

(B) Both statement-I and statement-II are false

(C) Statement-I is true but statement-II is false

(D) Statement-I is false but statement-II is true

Answer: (A)

8. Given below are two statements

Statement-I: A point charge is brought in an electric field. The value of electric field at a point near to the charge may increase if the charge is positive.

Statement-II: An electric dipole is placed in a non-uniform electric field. The net electric force on the dipole will not be zero.

Choose the correct answer from the options given below.

(A) Both statement-I and statement-II are true

(B) Both statement-I and statement-II are false

(C) Statement-I is true but statement-II is false

(D) Statement-I is false but statement-II is true

Answer: (A)

9. The three charges q/2, q and q/2 are placed at the corners A, B and C of a square of side ‘a’ as shown in figure. The magnitude of electric field (E) at the corner D of the square is

Answer: (A)

10. An infinitely long hollow conducting cylinder with radius R carries a uniform current along its surface.

Choose the correct representation of magnetic field (B) as a function of radial distance (r) from the axis of cylinder.

Answer: (B)

11. A radar sends an electromagnetic signal of electric field (E0) = 2.25 V/m and magnetic field (B0) = 1.5 × 10–8 T which strikes a target on line of sight at a distance of 3 km in a medium. After that, a part of signal (echo) reflects back towards the radar with same velocity and by same path. If the signal was transmitted at time t = 0 from radar, then after how much time echo will reach to the radar?

(A) 2.0 × 10–5 s

(B) 4.0 × 10–5 s

(C) 1.0 × 10–5 s

(D) 8.0 × 10–5 s

Answer: (B)

12. The refracting angle of a prism is A and refractive index of the material of the prism is cot (A/2). Then the angle of minimum deviation will be :

(A) 180 – 2A

(B) 90 – A

(C) 180 + 2A

(D) 180 – 3A

Answer: (A)

13. The aperture of the objective is 24.4 cm. The resolving power of this telescope, if a light of wavelength 2440 Å is used to see the object will be:

(A) 8.1 × 106

(B) 10.0 × 107

(C) 8.2 × 105

(D) 1.0 × 10–8

Answer: (C)

14. The de Broglie wavelengths for an electron and a photon are λe and λp, respectively. For the same kinetic energy of electron and photon, which of the following presents the correct relation between the de Broglie wavelengths of two?

Answer: (A)

15. The Q-value of a nuclear reaction and kinetic energy of the projectile particle, Kp are related as :

(A) Q = Kp

(B) (Kp + Q) < 0

(C) Q <Kp

(D) (Kp + Q) > 0

Answer: (D)

16. In the following circuit, the correct relation between output (Y) and inputs A and B will be:

(A)  Y = AB

(B)  Y = A + B

(C) 

(D) 

Answer: (C)

17. For using a multimeter to identify diode from electrical components, choose the correct statement out of the following about the diode:

(A) It is two terminal device which conducts current in both directions.

(B) It is two terminal device which conducts current in one direction only

(C) It does not conduct current gives an initial deflection which decays to zero.

(D) It is three terminal device which conducts current in one direction only between central terminal and either of the remaining two terminals.

Answer: (B)

18. Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A :n-p-n transistor permits more current than a p-n-p transistor.

Reason R: Electrons have greater mobility as a charge carrier.

Choose the correct answer from the options given below:

(A) Both A and Rare true, and R is correct explanation of A.

(B) Both A and R are true but R is NOT the correct explanation of A.

(C) A is true but R is false.

(D) A is false but R is true.

Answer: (A)

19. Match List-I with List-II.

Choose the correct answer from the options given below :

(A) A-I, B-II, C-III, D-IV

(B) A-IV, B-III, C-I, D-II

(C) A-IV, B-III, C-II, D-I

(D) A-I, B-II, C-IV, D-III

Answer: (C)

20. The velocity of sound in a gas, in which two wavelengths, 4.08 m and 4.16 m produce 40 beats in 12 s, will be:

(A) 282.8 ms–1

(B) 175.5 ms–1

(C) 353.6 ms–1

(D) 707.2 ms–1

Answer: (D)

SECTION-B

21. A pendulum is suspended by a string of length 250 cm. The mass of the bob of the pendulum is 200 g. The bob is pulled aside until the string is at 60° with vertical, as shown in the figure. After releasing the bob, the maximum velocity attained by the bob will be ___ ms–1. (if g = 10 m/s2)

Answer: (5)

22. A meter bridge setup is shown in the figure. It is used to determine an unknown resistance R using a given resistor of 15 Ω. The galvanometer (G) shows null deflection when tapping key is at 43 cm mark from end A. If the end correction for end A is 2 cm, then the determined value of R will be ___ Ω.

Answer: (19)

23. Current measured by the ammeter  in the reported circuit when no current flows through 10 Ω resistance, will be ___ A.

Answer: (10)

24. An AC source is connected to an inductance of 100 mH, a capacitance of 100 μF and a resistance of 120 Ω as shown in the figure. The time in which the resistance having a thermal capacity 2 J/°C will get heated by 16°C is _______ s.

Answer: (15)

25. The position vector of 1 kg object is  and its velocity  The magnitude of its angular momentum is √x Nm where x is _________.

Answer: (91)

26. A man of 60 kg is running on the road and suddenly jumps into a stationary trolly car of mass 120 kg. Then.thetrolly car starts moving with velocity 2 ms–1. The velocity of the running man was ___________ms–1. when he jumps into the car.

Answer: (6)

27. A hanging mass M is connected to a four times bigger mass by using a string-pulley arrangement. as shown in the figure. The bigger mass is placed on a horizontal ice-slab and being pulled by 2 Mg force. In this situation.tension in the string is x/5 Mg for x = _________. Neglect mass of the string and friction of the block (bigger mass) with ice slab. (Given g = acceleration due to gravity)

Answer: (6)

28. The total internal energy of two mole monoatomic ideal gas at temperature T = 300 K will be J. (Given R = 8.31 J/mol.K)

Answer: (7479)

29. A sing1y ionized magnesium atom (A24) ion is accelerated to kinetic energy 5 keV and is projected perpendicularly into a magnetic field B of the magnitude 0.5 T. The radius of path formed will be _________ cm.

Answer: (10)

30. A telegraph line of length loo km has a capacity of 0.01 µF/km and it carries an alternating current at 0.5 kilo cycle per second. If minimum impedance is required, then the value of the inductance that needs to be introduced in series is ________ mH. (if π = √10)

Answer: (100)

CHEMISTRY

SECTION-A

1. The incorrect statement about the imperfections in solids is :

(A) Schottky defect decreases the density of the substance.

(B) Interstitial defect increases the density of the substance.

(C) Frenkel defect does not alter the density of the substance.

(D) Vacancy defect increases the density of the substance.

Answer: (D)

2. The Zeta potential is related to which property of colloids?

(A) Colour

(B) Tyndall effect

(C) Charge on the surface of colloidal particles

(D) Brownian movement

Answer: (C)

3. Element “E” belongs to the period 4 and group 16 of the periodic table. The valence shell electron configuration of the element, which is just above “E” in the group is

(A) 3s2, 3p4

(B) 3d10, 4s2, 4p4

(C) 4d10, 5s2, 5p4

(D) 2s2, 2p4

Answer: (A)

4. Given are two statements one is labelled as Assertion A and other is labelled as Reason R.

Assertion A : Magnesium can reduce Al2O3 at a temperature below 1350°C, while above 1350°C aluminium can reduce MgO.

Reason R : The melting and boiling points of magnesium are lower than those of aluminium.

In light of the above statements, choose the most appropriate answer from the options given below :

(A) Both A and R are correct, and R is correct explanation of A.

(B) Both A and R are correct, but R is NOT the correct explanation of A.

(C) A is correct R is not correct.

(D) A is not correct, R is correct.

Answer: (B)

5. Dihydrogen reacts with CuO to give

(A) CuH2

(B) Cu

(C) Cu2O

(D) Cu(OH)2

Answer: (B)

6. Nitrogen gas is obtained by thermal decomposition of

(A) Ba(NO3)2

(B) Ba(N3)2

(C) NaNO2

(D) NaNO3

Answer: (B)

7. Given below are two statements :

Statement I: The pentavalent oxide of group-15 element, E2O5, is less acidic than trivalent oxide, E2O3, of the same element.

Statement II: The acidic character of trivalent oxide of group 15 elements, E2O3, decreases down the group.

In light of the above statements, choose most appropriate answer from the options given below:

(A) Both Statement I and Statement II are true

(B) Both Statement I and Statement II are false

(C) Statement I true, but Statement II is false

(D) Statement I false, but Statement II is true

Answer: (D)

8. Which one of the lanthanoids given below is the most stable in divalent form?

(A) Ce (Atomic Number 58)

(B) Sm (Atomic Number 62 )

(C) Eu (Atomic Number 63)

(D) Yb (Atomic Number 70)

Answer: (C)

9. Given below are two statements:

Statement I: [Ni(CN)4]2– is square planar and diamagnetic complex, with dsp2 hybridization for Ni but [Ni(CO)4] is tetrahedral, paramagnetic and with sp3-hybridization for Ni.

Statement II: [NiCl4]2– and [Ni(CO)4] both have same d-electron configuration, have same geometry and are paramagnetic.

In light of the above statements, choose the correct answer from the options given below :

(A) Both Statement I and Statement II are true

(B) Both Statement I and Statement II are false

(C) Statement I is correct but Statement II is false

(D) Statement I is incorrect but Statement II is true

Answer: (B)

10. Which amongst the following is not a pesticide?

(A) DDT

(B) Organophosphates

(C) Dieldrin

(D) Sodium arsenite

Answer: (D)

11. Which one of the following techniques is not used to spot components of a mixture separated on thin layer chromatographic plate?

(A) I2 (Solid)

(B) U.V. Light

(C) Visualisation agent as a component of mobile phase

(D) Spraying of an appropriate reagent

Answer: (C)

12. Which of the following structures are aromatic in nature?

(A) A, B, C and D

(B) Only A and B

(C) Only A and C

(D) Only B, C and D

Answer: (B)

13. The major product (P) in the reaction

Answer: (C)

14. The correct structure of product ‘A’ formed in the following reaction.

Answer: (A)

15. Which one of the following compounds is inactive towards SN1 reaction?

Answer: (C)

16. Identify the major product formed in the following sequence of reactions:

Answer: (C)

17. A primary aliphatic amine on reaction with nitrous acid in cold (273 K) and there after raising temperature of reaction mixture to room temperature (298 K), gives

(A) nitrile

(B) alcohol

(C) diazonium salt

(D) secondary amine

Answer: (B)

18. Which one of the following is NOT a copolymer?

(A) Buna-S

(B) Neoprene

(C) PHBV

(D) Butadiene-styrene

Answer: (B)

19. Stability of α-Helix structure of proteins depends upon

(A) dipolar interaction

(B) H-bonding interaction

(C) van der Walls forces

(D) π-stacking interaction

Answer: (B)

20. The formula of the purple colour formed in Laissaigne’s test for sulphur using sodium nitroprusside is

(A) NaFe[Fe(CN)6]

(B) Na[Cr(NH3)2(NCS)4]

(C) Na2[Fe(CN)5(NO)]

(D) Na4[Fe(CN)5(NOS)]

Answer: (D)

SECTION-B

21. A 2.0 g sample containing MnO2 is treated with HCl liberating Cl2. The Cl2 gas is passed into a solution of KI and 60.0 mL of 0.1 M Na2S2O3 is required to titrate the liberated iodine. The percentage of MnO2 in the sample is ______. (Nearest integer)

[Atomic masses (in u) Mn = 55; Cl = 35.5; O = 16, I = 127, Na = 23, K = 39, S = 32]

Answer: (13)

22. lf the work function of a metal is 6.63 × 10–19 J, the maximum wavelength of the photon required to remove a photoelectron from the metal is ______ nm. (Nearest integer)

[Given : h = 6.63 × 10–34 J s, and c = 3 × 108 m s–1]

Answer: (300)

23. The hybridization of P exhibited in PF5 is spxdy. The value of y is _______

Answer: (1)

24. 4.0 L of an ideal gas is allowed to expand isothermally into vacuum until the total volume is 20 L. The amount of heat absorbed in this expansion is _______ L atm.

Answer: (0)

25. The vapour pressures of two volatile liquids A and B at 25°C are 50 Torr and 100 Torr, respectively. If the liquid mixture, contains 0.3 mole fraction of A, then the mole fraction of liquid B in the vapour phase is x/17. The value of x is __________.

Answer: (14)

26. The solubility product of a sparingly soluble salt A2X3 is 1.1 × 10–23. If the specific conductance of the solution is 3 × 10–5 S m–1, the limiting molar conductivity of the solution is x × 10–3 S m2mol–1. The value of x is _______.

Answer: (3)

27. The quantity of electricity of Faraday needed to reduce 1 mol of Cr2O72 to Cr3+ is _________.

Answer: (6)

28. For a first order reaction A → B, the rate constant, k = 5.5 × 10–14 s–1. The time required for 67% completion of reaction is x × 10–1 times the half life of reaction. The value of x is _____ (Nearest integer)

(Given : log 3 = 0.4771)

Answer: (16)

29. Number of complexes which will exhibit synergic bonding amongst, [Cr(CO)6], [Mn(CO)5] and [Mn2(CO)10] is ________.

Answer: (3)

30. In the estimation of bromine, 0.5 g of an organic compound gave 0.40 g of silver bromide. The percentage of bromine in the given compound is _________% (nearest integer)

(Relative atomic masses of Ag and Br are 108u and 80u, respectively).

Answer: (34)

MATHEMATICS

SECTION-A

1. If  where α ∈ R, then the value of 16α is equal to

(A)  1411

(B)  1320

(C)  1615

(D)  1855

Answer: (A)

2. Let a function f : ℕ →ℕ be defined by

then, f is

(A) One-one but not onto

(B) Onto but not one-one

(C) Neither one-one nor onto

(D) One-one and onto

Answer: (D)

3. If the system of linear equations

2x + 3y – z = –2

x + y + z = 4

x – y + |λ|z = 4λ – 4

where λ∈ R, has no solution, then

(A) λ = 7

(B) λ = –7

(C) λ = 8

(D) λ2 = 1

Answer: (B)

4. Let A be a matrix of order 3 × 3 and det (A) = 2. Then det (det (A) adj (5 adj (A3))) is equal to ______.

(A) 512 × 106

(B) 256 × 106

(C) 1024 × 106

(D) 256 × 1011

Answer: (A)

5. The total number of 5-digit numbers, formed by using the digits 1, 2, 3, 5, 6, 7 without repetition, which are multiple of 6, is

(A)  36

(B)  48

(C)  60

(D)  72

Answer: (D)

6. Let A1, A2, A3, … be an increasing geometric progression of positive real numbers. If A1A3A5A7 = 1/1296 and A2 + A4 = 7/36 then, the value of A6 + A8 + A10 is equal to

(A)  33

(B)  37

(C)  43

(D)  47

Answer: (C)

7. Let [t] denote the greatest integer less than or equal to t. Then, the value of the integral  is equal to

Answer: (C)

8. Let f : ℝ→ℝ be defined as

Where a, b, c ∈ ℝ and [t] denotes greatest integer less than or equal to t. Then, which of the following statements is true?

(A) There exists a, b, c ∈  such that  f iscontinuous on ∈ .

(B) If f is discontinuous at exactly one point, then a + b + c = 1

(C) If f is discontinuous at exactly one point, then a + b + c ≠ 1

(D) f is discontinuous at atleast two points, for any values of a, b and c

Answer: (C)

9. The area of the region S = {(x, y) : y2≤ 8x, y ≥ √2x, x ≥ 1} is

(A)  13√2/6

(B)  11√2/6

(C)  5√2/6

(D)  19√2/6

Answer: (B)

10. Let the solution curve y = y(x) of the differential equation  pass through the points (1, 0) and (2α, α), α > 0. Then α is equal to

Answer: (A)

11. Let y = y(x) be the solution of the differential equation  x > 1, with y(2) = − Then y (3) is equal to

(A)  −18

(B)  −12

(C)  −6

(D)  −3

Answer: (A)

12. The number of real solutions of x7 + 5x3 + 3x + 1 = 0 is equal to ______.

(A)  0

(B)  1

(C)  3

(D)  5

Answer: (B)

13. Let the eccentricity of the hyperbola  and length of its latus rectum be 6√2, If y = 2x + c is a tangent to the hyperbola H. then the value of c2 is equal to

(A)  18

(B)  20

(C)  24

(D)  32

Answer: (B)

14. If the tangents drawn at the points O(0, 0) and P(1 + √5, 2) on the circle x2 + y2 – 2x – 4y = 0 intersect at the point Q, then the area of the triangle OPQ is equal to

Answer: (C)

15. If two distinct points Q, R lie on the line of intersection of the planes –x + 2y – z = 0 and 3x – 5y + 2z = 0 and PQ = PR = √18 where the point P is (1, –2, 3), then the area of the triangle PQR is equal to

Answer: (B)

16. The acute angle between the planes P1 and P2, when P1 and P2 are the planes passing through the intersection of the planes 5x + 8y + 13z – 29 = 0 and 8x – 7y + z – 20 = 0 and the points (2, 1, 3) and (0, 1, 2), respectively, is

(A)  π/3

(B)  π/4

(C)  π/6

(D)  π/12

Answer: (A)

17. Let the plane  contain the line of intersection of two planes  and  If the plane P passes through the point (2, 3, 1/2), then the value of  is equal to

(A)  90

(B)  93

(C)  95

(D)  97

Answer: (B)

18. The probability, that in a randomly selected 3-digit number at least two digits are odd, is

(A)  19/36

(B)  15/36

(C)  13/36

(D)  23/36

Answer: (A)

19. Let AB and PQ be two vertical poles, 160 m apart from each other. Let C be the middle point of B and Q, which are feet of these two poles. Let π/8 and θ be the angles of elevation from C to P and A, respectively. If the height of pole PQ is twice the height of pole AB, then tan2θ is equal to

Answer: (C)

20. Let p, q, r be three logical statements. Consider the compound statements

S1 : ((~p) ∨q) ∨ ((~p) ∨r) and

S2 :p→ (q∨r)

Then, which of the following is NOT true?

(A) If S2 is True, then S1 is True

(B) If S2is False, then S1 is False

(C) If S2 is False, then S1 is True

(D) If S1 is False, then S2 is False

Answer: (C)

SECTION-B

21. Let R1 and R2 be relations on the set {1, 2, ….., 50} such that R1 ={(p, pn) :p is a prime and n ≥ 0 is an integer} and R2 = {(p, pn) : p is a prime and n = 0 or 1}. Then, the number of elements in R1 – R2 is ______.

Answer: (8)

22. The number of real solutions of the equation e4x + 4e3x – 58e2x + 4ex + 1 = 0 is _____.

Answer: (2)

23. The mean and standard deviation of 15 observations are found to be 8 and 3, respectively. On rechecking, it was found that, in the observations, 20 was misread as 5. Then, the correct variance is equal to _______.

Answer: (7)

24. If  and  are coplanar vectors and  then 122 (c1 + c2 + c3) is equal to _________.

Answer: (150)

25. A ray of light passing through the point P(2, 3) reflects on the x-axis at point A and the reflected ray passes through the point Q(5, 4). Let R be the point that divides the line segment AQ internally into the ratio 2 : 1. Let the co-ordinates of the foot of the perpendicular M from R on the bisector of the angle PAQ be (α, β). Then, the value of 7α + 3β is equal to ___________.

Answer: (31)

26. Let l be a line which is normal to the curve y = 2x2 + x + 2 at a point P on the curve. If the point Q(6, 4) lies on the line l and O is origin, then the area of the triangle OPQ is equal to ___________.

Answer: (13)

27. Let A = {1, a1, a2…a18, 77} be a set of integers with 1 <a1< a2<….< a18< 77. Let the set A + A = {x + y :x, y ∈ A} contain exactly 39 elements. Then, the value of a1 + a2 +…+ a18 is equal to _____.

Answer: (702)

28. The number of positive integers k such that the constant term in the binomial expansion of  is 28. ℓ, where ℓ is an odd integer, is ____________.

Answer: (2)

29. The number of elements in the set {z = a + ib∈ ℂ: a, b ∈ ℤ and 1 < |z – 3 + 2i| < 4} is _________.

Answer: (40)

30. Let the lines y + 2x = √11 + 7√7 and 2y + x = 2√11 + 6√7 be normal to a circle C: (x – h)2 + (y – k)2 = r2. If the line  is tangent to the circle C, then the value of (5h – 8k)2 + 5r2 is equal to ________.

Answer: (816)

JEE Main Session 1 27th June 2022 Shift-1 Question Paper and Answer Key

JEE Main Session 1 27th June 2022 Shift 1

PHYSICS

Section-A

IMPORTANT INSTRUCTIONS:

(1)   The test is of 3 hours duration:

(2)   The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i)    Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

1. A projectile is launched at an angle ‘α’ with the horizontal with a velocity 20 ms–1. After10 s, its inclination with horizontal is ‘β’. The value of tanβ will be (g = 10 ms–2).

(A) tanα + 5secα

(B) tanα– 5secα

(C) 2tanα– 5secα

(D) 2tanα + 5secα

Answer: (B)

2. A girl standing on road holds her umbrella at 45° with the vertical to keep the rain away. Ifshe starts running without umbrella with a speed of 15√2 kmh–1, the rain drops hit herhead vertically. The speed of rain drops with respect to the moving girl is

(A)  30 kmh1

(B) 

(C) 

(D)  25 kmh1

Answer: (C)

3. A silver wire has a mass (0.6 ± 0.006) g, radius (0.5 ± 0.005) mm and length (4 ± 0.04) cm.The maximum percentage error in the measurement of its density will be

(A) 4%

(B) 3%

(C) 6%

(D) 7%

Answer: (A)

4. A system of two blocks of masses m = 2 kg and M = 8 kg is placed on a smooth table as shown in the figure. The coefficient of static friction between two blocks is 0.5. The maximum horizontal force F that can be applied to the block of mass M so that the blocks move together will be

(A) 9.8 N

(B) 39.2 N

(C) 49 N

(D) 78.4 N

Answer: (C)

5. Two blocks of masses 10 kg and 30 kg are placed on the same straight line with coordinates(0, 0) cm and (x, 0) cm respectively. The block of 10 kg is moved on the same line through a distance of 6 cm towards the other block. The distance through which the block of 30 kg must be moved to keep the position of centre of mass of the system unchanged is

(A) 4 cm towards the 10 kg block

(B) 2 cm away from the 10 kg block

(C) 2 cm towards the 10 kg block

(D) 4 cm away from the 10 kg block

Answer: (C)

6. A 72 Ω galvanometer is shunted by a resistance of 8 Ω. The percentage of the total current which passes through the galvanometer is

(A) 0.1%

(B) 10%

(C) 25%

(D) 0.25%

Answer: (B)

7. Given below are two statements.

Statement-I: The law of gravitation holds good for any pair of bodies in the universe.

Statement-II: The weight of any person becomes zero when the person is at the centre of the earth.

In the light of the above statements, choose the correct answer from the options given below

(A) Both Statement I and Statement II are true

(B) Both Statement I and Statement II are false

(C) Statement I is true but Statement II is false

(D) Statement I is false but Statement II is true

Answer: (A)

8. What percentage of kinetic energy of a moving particle is transferred to a stationary particle when it strikes the stationary particle of 5 times its mass? (Assume the collision to be head-on elastic collision)

(A)  50.0%

(B)  66.6%

(C)  55.6%

(D)  33.3%

Answer: (C)

9. The velocity of a small ball of mass ‘m’ and density d1, when dropped in a container filled with glycerine, becomes constant after some time. If the density of glycerine is d2, then the viscous force acting on the ball, will be

Answer: (B)

10. The susceptibility of a paramagnetic material is 99. The permeability of the material in Wb/A-m, is

[Permeability of free space μ0 = 4π × 10–7Wb/A-m]

(A) 4π × 10–7

(B) 4π × 10–4

(C) 4π × 10–5

(D) 4π × 10–6

Answer: (C)

11. The current flowing through an ac circuit is given by I = 5 sin(120πt)A. How long will the current take to reach the peak value starting from zero?

(A)  1/60 s

(B)  60 s

(C)  1/120 s

(D)  1/240 s

Answer: (D)

12. Mach List-I with List – II :

Choose the correct answer from the options given below :

(A) (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)

(B) (a)-(iii), (b)-(i), (c)-(ii), (d)-(iv)

(C) (a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)

(D) (a)-(iii), (b)-(iv), (c)-(i), (d)-(ii)

Answer: (A)

13. An α particle and a carbon 12 atom has same kinetic energy K. The ratio of their de-Broglie wavelengths (λα : λC12) is :

(A) 1: √3

(B) √3 : 1

(C) 3 : 1

(D) 2 : √3

Answer: (B)

14. A force of 10 N acts on a charged particle placed between two plates of a charged capacitor. If one plate of capacitor is removed, then the force acting on that particle will be

(A) 5 N

(B) 10 N

(C) 20 N

(D) Zero

Answer: (A)

15. The displacement of simple harmonic oscillator after 3 seconds starting from its mean position is equal to half of its amplitude. The time period of harmonic motion is :

(A) 6 s

(B) 8 s

(C) 12 s

(D) 36 s

Answer: (D)

16. An observer moves towards a stationary source of sound with a velocity equal to one-fifth of the velocity of sound. The percentage change in the frequency will be:

(A) 20%

(B) 10%

(C) 5%

(D) 0%

Answer: (A)

17. Consider a light ray travelling in air is incident into a medium of refractive index √2n. The incident angle is twice that of refracting angle. Then, the angle of incidence will be:

Answer: (D)

18. A hydrogen atom in its ground state absorbs 10.2 eV of energy. The angular momentum of electron of the hydrogen atom will increase by the value of:

(Given, Planck’s constant = 6.6 × 10–34Js).

(A) 2.10 × 10–34Js

(B) 1.05 × 10–34Js

(C) 3.15 × 10–34Js

(D) 4.2 × 10–34Js

Answer: (B)

19. Identify the correct Logic Gate for the following output (Y) of two inputs A and B.

Answer: (B)

20. A mixture of hydrogen and oxygen has volume 2000 cm3, temperature 300 K, pressure 100 kPa and mass 0.76 g. The ratio of number of moles of hydrogen to number of moles of oxygen in the mixture will be:

[Take gas constant R = 8.3 JK–1mol–1]

(A)  1/3

(B)  3/1

(C)  1/16

(D)  16/1

Answer: (B)

SECTION-B

21. In a carnot engine, the temperature of reservoir is 527°C and that of sink is 200 K. If the work done by the engine when it transfers heat from reservoir to sink is 12000 kJ, the quantity of heat absorbed by the engine from reservoir is ___ × 106

Answer: (16)

22. A 220 V, 50 Hz AC source is connected to a 25 V, 5 W lamp and an additional resistance R in series (as shown in figure) to run the lamp at its peak brightness, then the value of R (in ohm) will be ________.

Answer: (975)

23. In Young’s double slit experiment the two slits are 0.6 mm distance apart. Interference pattern is observed on a screen at a distance 80 cm from the slits. The first dark fringe is observed on the screen directly opposite to one of the slits. The wavelength of light will be _____ nm.

Answer: (450)

24. A beam of monochromatic light is used to excite the electron in Li++ from the first orbit to the third orbit. The wavelength of monochromatic light is found to be x × 1010 The value of x is ______. [Given hc = 1242 eV nm]

Answer: (114)

25. A cell, shunted by a 8 Ω resistance, is balanced across a potentiometer wire of length 3 m. The balancing length is 2 m when the cell is shunted by 4 Ω resistance. The value of internal resistance of the cell will be _______ Ω.

Answer: (8)

26. The current density in a cylindrical wire of radius 4 mm is 4 × 106 Am–2. The current through the outer portion of the wire between radial distances R/2 and R is _________π A.

Answer: (48)

27. A capacitor of capacitance 50pF is charged by 100 V source. It is then connected to another uncharged identical capacitor. Electrostatic energy loss in the process is ________nJ.

Answer: (125)

28. The height of a transmitting antenna at the top of a tower is 25 m and that of receiving antenna is, 49 m. The maximum distance between them, for satisfactory communication in LOS (Line-Of-Sight) is K√5 × 102 The value of K is ________. [Assume radius of Earth is 64 × 10+5 m] (Calculate upto nearest integer value)

Answer: (192)

29. The area of cross-section of a large tank is 0.5 m2. It has a narrow opening near the bottom having area of cross-section 1 cm2. A load of 25 kg is applied on the water at the top in the tank. Neglecting the speed of water in the tank, the velocity of the water, coming out of the opening at the time when the height of water level in the tank is 40 cm above the bottom, will be _______ cms–1. [Take g = 10 ms–2]

Answer: (300)

30. A pendulum of length 2 m consists of a wooden bob of mass 50 g. A bullet of mass 75 g is fired towards the stationary bob with a speed v. The bullet emerges out of the bob with a speed v/3 and the bob just completes the vertical circle. The value of v is ________ ms–1. (if g = 10 m/s2)

Answer: (10)

CHEMISTRY

SECTION-A

1. Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : At 10°C, the density of a 5 M solution of KCl [atomic masses of K &Cl are 39 & 35.5 g mol–1 respectively], is ‘x’ g ml–1. The solution is cooled to –21°C. The molality of the solution will remain unchanged.

Reason (R) : The molality of a solution does not change with temperature as mass remains unaffected with temperature.

In the light of the above statements, choose the correct answer from the options given below.

(A) Both (A) and (R) are true and (R) is the correct explanation of (A).

(B) Both (A) and (R) are true but (R) is not the correct explanation of (A).

(C) (A) is true but (R) is false.

(D) (A) is false but (R) is true.

Answer: (A)

2. Based upon VSEPR theory, match the shape (geometry) of the molecules in List-I with the molecules in List-II and select the most appropriate option.

List-I                                List-II

(Shape)                            (Molecules)

(A) T-shaped                    (I) XeF4

(B) Trigonal planar           (II) SF4

(C) Square planar             (III) CIF3

(D) See-saw                     (IV) BF3

(A) (A)-(I), (B)-(II), (C)-(III), (D)-(IV)

(B) (A)-(III), (B)-(IV), (C)-(I), (D)-(II)

(C) (A)-(III), (B)-(IV), (C)-(II), (D)-(I)

(D) (A)-(IV), (B)-(III), (C)-(I), (D)-(II)

Answer: (B)

3. Match List-I with List-II

List-I

(A) Spontaneous process

(B) Process with ΔP = 0, ΔT = 0

(C) ΔHreaction

(D) Exothermic Process

List-II

(I) ΔH < 0

(II) ΔGT,P< 0

(III) Isothermal and isobaric process

(IV) [Bond energies of molecules in reactants] – [Bond energies of product molecules]

Choose the correct answer from the options given below :

(A) (A)-(III), (B)-(II), (C)-(IV), (D)-(I)

(B) (A)-(II), (B)-(III), (C)-(IV), (D)-(I)

(C) (A)-(II), (B)-(III), (C)-(I), (D)-(IV)

(D) (A)-(II), (B)-(I), (C)-(III), (D)-(IV)

Answer: (B)

4. Match List-I with List-II

List-I                                            List-II

(A) Lyophilic colloid       (I) Liquid-liquid colloid

(B) Emulsion                    (II) Protective colloid

(C) Positively charged     (III)FeCl3+NaOHcolloid

(D) Negatively charged   (IV)FeCl3+hotwatercolloid

Choose the correct answer from the options given below :

(A) (A)-(II), (B)-(I), (C)-(IV), (D)-(III)

(B) (A)-(III), (B)-(I), (C)-(IV), (D)-(II)

(C) (A)-(II), (B)-(I), (C)-(III), (D)-(IV)

(D) (A)-(III), (B)-(II), (C)-(I), (D)-(IV)

Answer: (A)

5. Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : The ionic radii of O2– and Mg2+ are same.

Reason (R) : Both O2– and Mg2+ are isoelectronic species.

In the light of the above statements, choose the correct answer from the options given below.

(A) Both (A) and (R) are true and (R) is the correct explanation of (A).

(B) Both (A) and (R) are true but (R) is not the correct explanation of (A).

(C) (A) is true but (R) is false.

(D) (A) is false but (R) is true.

Answer: (D)

6. Match List-I with List-II.

List-I                                List-II

(A) Concentration of       (I) AnilineGold ore

(B) Leaching of alumina (II) NaOH

(C) Froth stabiliser           (III) SO2

(D) Blister copper            (IV) NaCN

Choose the correct answer from the options given below.

(A) (A)-(IV), (B)-(III), (C)-(II), (D)-(I)

(B) (A)-(IV), (B)-(II), (C)-(I), (D)-(III)

(C) (A)-(III), (B)-(II), (C)-(I), (D)-(IV)

(D) (A)-(II), (B)-(IV), (C)-(III), (D)-(I)

Answer: (B)

7. Addition of H2SO4 to BaO2 produces:

(A) BaO, SO2 and H2O

(B) BaHSO4 and O2

(C) BaSO4, H2 and O2

(D) BaSO4 and H2O2

Answer: (D)

8. BeCI2 reacts with LiAIH4 to give:

(A) Be + Li[AICI4] + H2

(B) Be + AIH3 + LiCI + HCI

(C) BeH2 + LiCI + AICI3

(D) BeH2 + Li[AICI4]

Answer: (C)

9. Match List-I with List-II

Choose the correct answer from the options given below:

(A) (A)-(III), (B)-(II), (C)-(I), (D)-(IV)

(B) (A)-(IV), (B)-(I), (C)-(II), (D)-(III)

(C) (A)-(II), (B)-(I), (C)-(IV), (D)-(III)

(D) (A)-(III), (B)-(IV), (C)-(I), (D)-(II)

Answer: (D)

10. Heating white phosphorus with conc. NaOH solution gives mainly:

(A) Na3P and H2O

(B) H3PO and NaH

(C) P(OH)3 and NaH2PO4

(D) PH3 and NaH2PO2

Answer: (D)

11. Which of the following will have maximum stabilization due to crystal field?

(A) [Ti(H2O)6]3+

(B) [Co(H2O)6]2+

(C) [Co(CN)6]–3

(D) [Cu(NH3)4]2+

Answer: (C)

12. Given below are two Statements:

Statement I: Classical smog occurs in cool humid climate. It is a reducing mixture of smoke, fog and sulphur dioxide.

Statement II: Photochemical smog has components, ozone, nitric oxide, acrolein, formaldehyde, PAN etc.

In the light of the above statements, choose the most appropriate answer from the options given below.

(A) Both Statement I and Statement II are correct.

(B) Both Statement I and Statement II are incorrect.

(C) Statement I is correct but Statement II is incorrect.

(D) Statement I is incorrect but Statement II is correct

Answer: (A)

13. Which of the following is structure of a separating funnel?

Answer: (A)

14. ‘A’ and ‘B’ respectively are:

(A) 1-methylcyclohex-1, 3-diene &cyclopentene

(B) Cyclohex-1, 3-diene &cyclopentene

(C) 1-methylcyclohex-1, 4-diene & 1-methylcyclo-pent-ene

(D) Cyclohex-1, 3-diene & 1-methylcyclopent-1-ene

Answer: (D)

15. The major product of the following reaction is:

Answer: (A)

16. Which of the following reactions will yield benzaldehyde as a product?

(A) (B) and (C)

(B) (C) and (D)

(C) (A) and (D)

(D) (A) and (C)

Answer: (C)

17. Given below are two statements:

Statement-I : In Hofmann degradation reaction, the migration of only an alkyl group takes place from carbonyl carbon of the amide to the nitrogen atom.

Statement-II : The group is migrated in Hofmann degradation reaction to electron deficient atom.

In the light of the above statements, choose the most appropriate answer from the options given below:

(A) Both Statement I and Statement II are correct

(B) Both Statement I and Statement II are incorrect

(C) Statement I is correct but Statement II is incorrect

(D) Statement I is incorrect but Statement II is correct

Answer: (D)

18. Match List-I with List-II

Choose the correct answer from the options given below:

(A) (A) –(II) (B) – (III), (C) – (IV), (D) – (I)

(B) (A) –(I) (B) – (II), (C) – (III), (D) – (IV)

(C) (A) –(IV) (B) – (III), (C) – (II), (D) – (I)

(D) (A) –(II) (B) – (III), (C) – (I), (D) – (IV)

Answer: (A)

19. L-isomer of a compound ‘A’ (C4H8O4) gives a positive test with [Ag(NH3)2]+. Treatment of ‘A’ with acetic anhydride yields triacetate derivative. Compound ‘A’ produces an optically active compound (B) and an optically inactive compound (C) on treatment with bromine water and HNO3 Compound (A) is:

Answer: (A)

20. Match List-I with List-II

List-II

(I) Dishwashing power

(II) Toothpaste

(III) Laundry soap

(IV) Hair conditional

Choose the correct answer from the options given below:

(A) (A) –(III) (B) – (II), (C) – (IV), (D) – (I)

(B) (A) –(IV) (B) – (II), (C) – (III), (D) – (I)

(C) (A) –(IV) (B) – (III), (C) – (II), (D) – (I)

(D) (A) –(III) (B) – (IV), (C) – (I), (D) – (II)

Answer: (B)

SECTION-B

21. Metal deficiency defect is shown by Fe93O. In the crystal, some Fe2+cations are missing and loss of positive charge is compensated by the presence of Fe3+ ions. The percentage of Fe2+ ions in the Fe0.93O crystals is ______. (Nearest integer)

Answer: (85)

22. If the uncertainty in velocity and position of a minute particle in space are, 2.4 × 10–26 (m s–1) and 10–7 (m), respectively. The mass of the particle in g is ________. (Nearest integer)

(Given : h = 6.626 × 10–34Js)

Answer: (22)

23. 2 g of a non-volatile non-electrolyte solute is dissolved in 200 g of two different solvents A and B whose ebullioscopic constants are in the ratio of 1 : 8. The elevation in boiling points of A and B are in the ratio  The value of y is ______. (Nearest Integer)

Answer: (8)

24. 2NOCl(g) ⇌ 2NO(g) + Cl2(g)

In an experiment, 2.0 moles of NOCl was placed in a one-litre flask and the concentration of NO after equilibrium established, was found to be 0.4 mol/ L. The equilibrium constant at 30°C is ________ × 10–4.

Answer: (125)

25. The limiting molar conductivities of NaI, NaNO3 and AgNO3 are 12.7, 12.0 and 13.3 mS m2mol–1, respectively (all at 25°C). The limiting molar conductivity of Agl at this temperature is ________ mS m2mol–1.

Answer: (14)

26. The rate constant for a first order reaction is given by the following equation :

The activation energy for the reaction is given by ______ kJ mol–1. (In nearest integer)

(Given : R = 8.3 J K–1mol–1)

Answer: (166)

27. The number of statement(s) correct from the following for Copper (at. no. 29) is/are ______.

(A) Cu(II) complexes are always paramagnetic

(B) Cu(I) complexes are generally colourless

(C) Cu(I) is easily oxidized

(D) In Fehling solution, the active reagent has Cu(I)

Answer: (3)

28. Acidified potassium permanganate solution oxidises oxalic acid. The spin-only magnetic moment of the manganese product formed from the above reaction is ______ B.M. (Nearest Integer)

Answer: (6)

29. Two elements A and B which form 0.15 moles of A2B and AB3 type compounds. If both A2B and AB3 weigh equally, then the atomic weight of A is _____ times of atomic weight of B.

Answer: (2)

30. Total number of possible stereoisomers of dimethyl cyclopentane is _______.

Answer: (6)

MATHEMATICS

SECTION-A

1. The area of the polygon, whose vertices are the non-real roots of the equation  is :

(A)  3√3/4

(B)  3√3/2

(C)  3/2

(D)  3/4

Answer: (A)

2. Let the system of linear equations x + 2y + z = 2, αx + 3y – z = α, –αx + y + 2z = –α be inconsistent. Then α is equal to :

(A)  5/2

(B)  −5/2

(C)  7/2

(D)  −7/2

Answer: (D)

3. If  where a, b, c are in A.P. and |a| < 1, |b| < 1, |c| < 1, abc ≠ 0,

(A) x, y, zare in A.P.

(B) x, y, zare in G.P.

(C)  1/x, 1/y, 1/z are in A.P.

(D) 

Answer: (C)

4. Let  where a, b, c are constants, represent a circle passing through the point (2, 5). Then the shortest distance of the point (11, 6) from this circle is

(A)  10

(B)  8

(C)  7

(D)  5

Answer: (B)

5. Let a be an integer such that  exists, where [t] is greatest integer ≤ t. Then a is equal to :

(A)  −6

(B)  −2

(C)  2

(D)  6

Answer: (A)

6. The number of distinct real roots of x4 – 4x + 1 = 0 is :

(A)  4

(B)  2

(C)  1

(D)  0

Answer: (B)

7. The lengths of the sides of a triangle are 10 + x2, 10 + x2 and 20 – 2x2. If for x = k, the area of the triangle is maximum, then 3k2 is equal to :

(A)  5

(B)  8

(C)  10

(D)  12

Answer: (C)

8. If  then:

(A) x2y′′ + xy′ – 25y = 0

(B) x2y′′ – xy′ – 25y = 0

(C) x2y′′ – xy′+ 25y = 0

(D) x2y′′ + xy′+ 25y = 0

Answer: (D)

9. where C is a constant, then at x = 1 is equal to :

(A)  −3/4

(B)  3/4

(C)  −3/2

(D)  3/2

Answer: (B)

10. The value of the integral is equal to:

(A)  5e2

(B)  3e2

(C)  4

(D)  6

Answer: (D)

11. If x, y > 0, y(1) = 1, then y(2) is equal to :

(A) 2 + log2 3

(B) 2 + log3 2

(C) 2 – log3 2

(D) 2 – log2 3

Answer: (D)

12. In an isosceles triangle ABC, the vertex A is (6, 1) and the equation of the base BC is 2x + y = 4. Let the point B lie on the line x + 3y = 7. If (α, β) is the centroid of ΔABC, then 15(α + β) is equal to :

(A)  39

(B)  41

(C)  51

(D)  63

Answer: (C)

13. Let the eccentricity of an ellipse  a > b, be 1/4. If this ellipse passes through the point  then a2 + b2 is equal to :

(A)  29

(B)  31

(C)  32

(D)  34

Answer: (B)

14. If two straight lines whose direction cosines are given by the relations l + m – n = 0, 3l2 + m2 + cnl = 0 are parallel, then the positive value of c is :

(A)  6

(B)  4

(C)  3

(D)  2

Answer: (A)

15. Let  Then the number of vectors  and  is:

(A)  0

(B)  1

(C)  2

(D)  3

Answer: (A)

16. Five numbers, x1, x2, x3, x4, x5 are randomly selected from the numbers 1, 2, 3,….., 18 and are arranged in the increasing order (x1 < x2< x3< x4< x5). The probability that x2 = 7 and x4 = 11 is:

(A)  1/136

(B)  1/72

(C)  1/68

(D)  1/34

Answer: (C)

17. Let X be a random variable having binomial distribution B(7, p). If P(X = 3) = 5P(X = 4), then the sum of the mean and the variance of X is:

(A)  105/16

(B)  7/16

(C)  77/36

(D)  49/16

Answer: (C)

18. The value of  is equal to:

(A)  −1

(B)  −1/2

(C)  −1/3

(D)  −1/4

Answer: (B)

19.  is equal to:

(A)  11π/12

(B)  17π/12

(C)  31π/12

(D)  −3π/4

Answer: (A)

20. The boolean expression (~(p ∧q)) ∨q is equivalent to:

(A) q (p ∧q)

(B) pq

(C) p (pq)

(D) p (p∨q)

Answer: (D)

SECTION-B

21. Let f : R R be a function defined by Then  is equal to _______.

Answer: (99)

22. If the sum of all the roots of the equation  is logep, then p is equal to ________.

Answer: (45)

23. The positive value of the determinant of the matrix A, whose  is _______.

Answer: (14)

24. The number of ways, 16 identical cubes, of which 11 are blue and rest are red, can be placed in a row so that between any two red cubes there should be at least 2 blue cubes, is _________.

Answer: (56)

25. If the coefficient of x10 in the binomial expansion of  where l, k∈N and l is co-prime to 5, then k is equal to ___________.

Answer: (5)

26. Let

A1 = {(x, y) : |x| ≤ y2, |x| + 2y ≤ 8} and

A2 = {(x, y) : |x| + |y| ≤ k}. If 27 (Area A1) = 5 (Area A2), then k is equal to :

Answer: (6)

27. If the sum of the first ten terms of the series  where m and n are co-prime numbers, then m + n is equal to __________.

Answer: (276)

28. A rectangle R with end points of one of its sides as (1, 2) and (3, 6) is inscribed in a circle. If the equation of a diameter of the circle is

2x – y + 4 = 0, then the area of R is ________.

Answer: (16)

29. A circle of radius 2 unit passes through the vertex and the focus of the parabola y2 = 2x and touches the parabola  where α > 0. Then (4α – 8)2 is equal to ___________.

Answer: (63)

30. Let the mirror image of the point (a, b, c) with respect to the plane 3x – 4y + 12z + 19 = 0 be (a – 6, β, γ). If a + b + c = 5, then 7β – 9γ is equal to __________.

Answer: (137)

JEE Main Session 1 26th June 2022 Shift-1 Question Paper and Answer Key

JEE Main Session 1 26th June 2022 Shift 1

IMPORTANT INSTRUCTIONS:

(1) The test is of 3 hours duration:

(2) The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i) Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and −1 mark for wrong answer.

(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

PHYSICS

Section-A

1. An expression for a dimensionless quantity P is given by  where α and β are constants, x is distance; k is Boltzmann constant and t is the temperature. Then the dimensions of α will be

(A) [M0L–1T0]

(B) [ML0T–2]

(C) [MLT–2]

(D) [ML2T–2]

Answer: (C)

2. A person is standing in an elevator. In which situation, he experiences weight loss?

(A) When the elevator moves upward with constant acceleration

(B) When the elevator moves downward with constant acceleration

(C) When the elevator moves upward with uniform velocity

(D) When the elevator moves downward with uniform velocity

Answer: (B)

3. An object is thrown vertically upwards. At its maximum height, which of the following quantity becomes zero?

(A) Momentum

(B) Potential Energy

(C) Acceleration

(D) Force

Answer: (A)

4. A ball is released from rest from point P of a smooth semi-spherical vessel as shown in figure. The ratio of the centripetal force and normal reaction on the ball at point Q is A while angular position of point Q is α with respect to point P. Which of the following graphs represent the correct relation between A and α when ball goes from Q to R?

Answer: (C)

5. A thin circular ring of mass M and radius R is rotating with a constant angular velocity 2 rad s–1 in a horizontal plane about an axis vertical to its plane and passing through the center of the ring. If two objects each of mass m be attached gently to the opposite ends of a diameter of ring, the ring will then rotate with an angular velocity (in rad s–1).

Answer: (C)

6. The variation of acceleration due to gravity (g) with distance (r) from the center of the earth is correctly represented by

(Given R = radius of earth)

Answer: (A)

7. The efficiency of a Carnot’s engine, working between steam point and ice point, will be

(A)  26.81%

(B)  37.81%

(C)  47.81%

(D)  57.81%

Answer: (A)

8. Time period of a simple pendulum in a stationary lift is ‘T’. If the lift accelerates with g/6 vertically upwards then the time period will be

(Where g = acceleration due to gravity)

Answer: (C)

9. A thermally insulated vessel contains an ideal gas of molecular mass M and ratio of specific heats 1.4. Vessel is moving with speed ν and is suddenly brought to rest. Assuming no heat is lost to the surrounding and vessel temperature of the gas increases by

(R = universal gas constant)

Answer: (B)

10. Two capacitors having capacitance C1 and C2 respectively are connected as shown in figure. Initially, capacitor C1 is charged to a potential difference V volt by a battery. The battery is then removed and the charged capacitor C1 is now connected to uncharged capacitor C2 by closing the switch S. The amount of charge on the capacitor C2, after equilibrium, is

Answer: (A)

11. Given below two statements: One is labelled as Assertion (A) and other is labelled as Reason (R).

Assertion (A) : Non-polar materials do not have any permanent dipole moment.

Reason (R) : When a non-polar material is placed in an electric field, the centre of the positive charge distribution of it’s individual atom or molecule coincides with the centre of the negative charge distribution.

In the light of above statements, choose the most appropriate answer from the options given below.

(A) Both (A) and (R) are correct and (R) is the correct explanation of (A).

(B) Both (A) and (R) are correct and (R) is not the correct explanation of (A).

(C) (A) is correct but (R) is not correct.

(D) (A) is not correct but (R) is correct.

Answer: (C)

12. The magnetic flux through a coil perpendicular to its plane is varying according to the relation φ = (5t3 + 4t2 + 2t – 5) Weber. If the resistance of the coil is 5 ohm, then the induced current through the coil at t = 2 s will be,

(A) 15.6 A

(B) 16.6 A

(C) 17.6 A

(D) 18.6 A

Answer: (A)

13. An aluminium wire is stretched to make its length, 0.4% larger. The percentage change in resistance is :

(A)  0.4%

(B)  0.2%

(C)  0.8%

(D)  0.6%

Answer: (C)

14. A proton and an alpha particle of the same velocity enter in a uniform magnetic field which is acting perpendicular to their direction of motion. The ratio of the radii of the circular paths described by the alpha particle and proton is :

(A)  1:4

(B)  4:1

(C)  2:1

(D)  1:2

Answer: (C)

15. If electric field intensity of a uniform plane electro-magnetic wave is given as  Then, magnetic intensity ‘H’ of this wave in Am–1 will be :

[Given : Speed of light in vacuum c = 3 × 108ms–1, Permeability of vacuum μ0 = 4π × 10–7 NA–2]

Answer: (C)

16. In free space, an electromagnetic wave of 3 GHz frequency strikes over the edge of an object of size λ/100, where λ is the wavelength of the wave in free space. The phenomenon, which happens there will be:

(A) Reflection

(B) Refraction

(C) Diffraction

(D) Scattering

Answer: (D)

17. An electron with speed υ and a photon with speed c have the same de-Broglie wavelength. If the kinetic energy and momentum of electron are Ee and pe and that of photon are Eph and pph respectively. Which of the following is correct?

Answer: (B)

18. How many alpha and beta particles are emitted when Uranium 92U238 decays to lead 82Pb206?

(A) 3 alpha particles and 5 beta particles

(B) 6 alpha particles and 4 beta particles

(C) 4 alpha particles and 5 beta particles

(D) 8 alpha particles and 6 beta particles

Answer: (D)

19. The I-V characteristics of a p-n junction diode in forward bias is shown in the figure. The ratio of dynamic resistance, corresponding to forward bias voltage of 2 V and 4 V respectively, is :

(A)  1 : 2

(B)  5 : 1

(C)  1 : 40

(D)  20 : 1

Answer: (B)

20. Choose the correct statement for amplitude modulation :

(A) Amplitude of modulating signal is varied in accordance with the information signal.

(B) Amplitude of modulated signal is varied in accordance with the information signal.

(C) Amplitude of carrier signal is varied in accordance with the information signal.

(D) Amplitude of modulated signal is varied in accordance with the modulating signal.

Answer: (C)

SECTION-B

21. A fighter jet is flying horizontally at a certain altitude with a speed of 200 ms–1. When it passes directly overhead an anti-aircraft gun, a bullet is fired from the gun, at an angle θ with the horizontal, to hit the jet. If the bullet speed is 400 m/s, the value of θ will be _______°.

Answer: (60)

22. A ball of mass 0.5 kg is dropped from the height of 10 m. The height, at which the magnitude of velocity becomes equal to the magnitude of acceleration due to gravity, is ___ m.

[Use g = 10 m/s2]

Answer: (5)

23. The elastic behaviour of material for linear stress and linear strain, is shown in the figure. The energy density for a linear strain of 5 × 10–4 is ____ kJ/m3. Assume that material is elastic upto the linear strain of 5 × 10–4.

Answer: (25)

24. The elongation of a wire on the surface of the earth is 10–4 The same wire of same dimensions is elongated by 6 × 10–5 m on another planet. The acceleration due to gravity on the planet will be _________ ms–2. (Take acceleration due to gravity on the surface of earth = 10 ms–2)

Answer: (6)

25. A 10 Ω, 20 mH coil carrying constant current is connected to a battery of 20 V through a switch. Now after switch is opened current becomes zero in 100 μs. The average e.m.f. induced in the coil is __________V.

Answer: (400)

26. A light ray is incident, at an incident angle θ1, on the system of two plane mirrors M1 and M2 having an inclination angle 75° between them (as shown in figure). After reflecting from mirror M1 it gets reflected back by the mirror M2 with an angle of reflection 30°. The total deviation of the ray will be ________ degree.

Answer: (210)

27. In a vernier callipers, each cm on the main scale is divided into 20 equal parts. If tenth vernier scale division coincides with nineth main scale division. Then the value of vernier constant will be __________ ×10–2

Answer: (5)

28. As per the given circuit, the value of current through the battery will be ______ A.

Answer: (1)

29. A 110 V,50 Hz, AC source is connected in the circuit (as shown in figure). The current through the resistance 55Ω, at resonance in the circuit, will be _______ A.

Answer: (0)

30. An ideal fluid of density 800 kgm–3, flows smoothly through a bent pipe (as shown in figure) that tapers in cross-sectional area from a to a/2. The pressure difference between the wide and narrow sections of pipe is 4100 Pa. At wider section, the velocity of fluid is  for x = ___________ (Given g = 10 m−2)

Answer: (363)

CHEMISTRY

SECTION-A

1. A commercially sold conc. HCl is 35% HCl by mass. If the density of this commercial acid is 1.46 g/mL, the molarity of this solution is :

(Atomic mass : Cl = 35.5 amu, H = 1 amu)

(A) 10.2 M

(B) 12.5 M

(C) 14.0 M

(D) 18.2 M

Answer: (C)

2. An evacuated glass vessel weighs 40.0 g when empty, 135.0 g when filled with a liquid of density 0.95 g mL–1 and 40.5 g when filled with an ideal gas at 0.82 atm at 250 K. The molar mass of the gas in g mol–1 is:

(Given : R = 0.082 L atm K–1 mol–1)

(A)  35

(B)  50

(C)  75

(D)  125

Answer: (D)

3. If the radius of the 3rd Bohr’s orbit of hydrogen atom is r3 and the radius of 4th Bohr’s orbit is r4. Then :

Answer: (B)

4. Consider the ions/molecules

For  increasing bond order the correction  option is:

Answer: (A)

5. The (∂E/∂T)P of different types of half cells are as follows:

(Where E is the electromotive force)

Which of the above half cells would be preferred to be used as reference electrode?

(A)  A

(B)  B

(C)  C

(D)  D

Answer: (C)

6. Choose the correct stability order of group 13 elements in their +1 oxidation state.

(A) Al < Ga < In < Tl

(B) Tl < In < Ga < Al

(C) Al < Ga < Tl < In

(D) Al < Tl < Ga < In

Answer: (A)

7. Given below are two statements:

Statement I: According to the Ellingham diagram, any metal oxide with higher ΔG° is more stable than the one with lower ΔG°.

Statement II: The metal involved in the formation of oxide placed lower in the Ellingham diagram can reduce the oxide of a metal placed higher in the diagram.

In the light of the above statements, choose the most appropriate answer from the options given below:

(A) Both Statement I and Statement II are correct.

(B) Both Statement I and Statement II are incorrect.

(C) Statement I is correct but Statement II is incorrect.

(D) Statement I is incorrect but Statement II is correct.

Answer: (D)

8. Consider the following reaction:

The dihedral angle in product A in its solid phase at 110 K is :

(A) 104°

(B) 111.5°

(C) 90.2°

(D) 111.0°

Answer: (C)

9. The correct order of melting point is :

(A) Be > Mg > Ca > Sr

(B) Sr > Ca > Mg > Be

(C) Be > Ca > Mg > Sr

(D) Be > Ca > Sr > Mg

Answer: (D)

10. The correct order of melting points of hydrides of group 16 elements is:

(A) H2S < H2Se < H2Te < H2O

(B) H2O < H2S < H2Se < H2Te

(C) H2S < H2Te < H2Se < H2O

(D) H2Se < H2S < H2Te < H2O

Answer: (A)

11. Consider the following reaction:

A + alkali → B (Major Product)

If B is an oxoacid of phosphorus with no P-H bond, then A is:

(A) White P4

(B) Red P4

(C) P2O3

(D) H3PO3

Answer: (B)

12. Polar stratospheric clouds facilitate the formation of:

(A) ClONO2

(B) HOCl

(C) ClO

(D) CH4

Answer: (B)

13. Given below are two statements:

Statement I: In ‘Lassaigne’s Test’, when both nitrogen and sulphur are present in an organic compound, sodium thiocyanate is formed.

Statement II: If both nitrogen and sulphur are present in an organic compound, then the excess of sodium used in sodium fusion will decompose the sodium thiocyanate formed to give NaCN and Na2S.

In the light of the above statements, choose the most appropriate answer from the options given below:

(A) Both Statement I and Statement II are correct.

(B) Both Statement I and Statement II are incorrect.

(C) Statement I is correct but Statement II is incorrect.

(D) Statement I is incorrect but Statement II is correct.

Answer: (A)

14. 

Consider the above reaction and identify the intermediate ‘X’

Answer: (D)

15. 

Consider the above reaction sequence and identify the product B.

Answer: (A)

16. Which will have the highest enol content?

Answer: (C)

17. Among the following structures, which will show the most stable enamine formation?

(Where Me is –CH3)

Answer: (C)

18. Which of the following sets are correct regarding polymer?

(A) Copolymer : Buna-S

(B) Condensation polymer : Nylon-6,6

(C) Fibres : Nylon-6,6

(D) Thermosetting polymer : Terylene

(E) Homopolymer : Buna-N

Choose the correct answer from given options below:

(A) (A), (B) and (C) are correct

(B) (B), (C) and (D) are correct

(C) (A), (C) and (E) are correct

(D) (A), (B) and (D) are correct

Answer: (A)

19. A chemical which stimulates the secretion of pepsin is:

(A) Anti-histamine

(B) Cimetidine

(C) Histamine

(D) Zantac

Answer: (C)

20. Which statement is not true with respect to nitrate ion test?

(A) A dark brown ring is formed at the junction of two solutions.

(B) Ring is formed due to nitroferrous sulphate complex.

(C) The brown complex is [Fe(H2O)5 (NO)]SO4.

(D) Heating the nitrate salt with conc. H2SO4, light brown fumes are evolved.

Answer: (B)

SECTION-B

21. For complete combustion of methanol

the amount of heat produced as measured by bomb calorimeter is 726 kJ mol–1 at 27°C. The enthalpy of combustion for the reaction is –x kJ mol–1, where x is _________. (Nearest integer)

(Given : R= 8.3 JK–1 mol–1)

Answer: (727)

22. A 0.5 per cent solution of potassium chloride was found to freeze at –0.24°C. The percentage dissociation of potassium chloride is ______. (Nearest integer)

(Molal depression constant for water is 1.80 K kg mol–1 and molar mass of KCl is74.6 g mol–1)

Answer: (98)

23. 50 mL of 0.1 M CH3COOH is being titrated against 0.1 M NaOH. When 25 mL of NaOH has been added, the pH of the solution will be ____ × 10–2. (Nearest integer)

(Given : pKa (CH3COOH) = 4.76)

log 2 = 0.30

log 3 = 0.48

log 5 = 0.69

log 7 = 0.84

log 11 = 1.04

Answer: (476)

24. A flask is filled with equal moles of A and B. The half lives of A and B are 100 s and 50 s respectively and are independent of the initial concentration. The time required for the concentration of A to be four times that of B is ________s.

(Given : In 2 = 0.693)

Answer: (200)

25. 2.0 g of H2 gas is adsorbed on 2.5 g of platinum powder at 300 K and 1 bar pressure. The volume of the gas adsorbed per gram of the adsorbent is _____ mL.

Answer: (9960)

26. The spin-only magnetic moment value of the most basic oxide of vanadium among V2O3, V2O4 and V2O5 is ______ B.M. (Nearest integer)

Answer: (3)

27. The spin-only magnetic moment value of an octahedral complex among CoCl3⋅4NH3, NiCl2⋅6H2O and PtCl4⋅2HCl, which upon reaction with excess of AgNO3 gives 2 moles of AgCl is _______ B.M. (Nearest Integer)

Answer: (3)

28. On complete combustion 0.30 g of an organic compound gave 0.20 g of carbon dioxide and 0.10 g of water. The percentage of carbon in the given organic compound is ______. (Nearest Integer)

Answer: (18)

29. Compound ‘P’ on nitration with dil. HNO3 yields two isomers (A) and (B) show the intramolecular and intermolecular hydrogen bonding respectively. Compound (P) on reaction with conc. HNO3 yields a yellow compound ‘C’, a strong acid. The number of oxygen atoms is present in compound ‘C’ _______

Answer: (7)

30. The number of oxygens present in a nucleotide formed from a base, that is present only in RNA is ________.

Answer: (9)

MATHEMATICS

SECTION-A

1. Let  x ∈ R – {0, −1, 1). If fn+1(x) = f(fn(x)) for all n ∈ N, then f6(6) + f7(7) is equal to:

(A)  7/6

(B)  −3/2

(C)  7/12

(D)  −11/12

Answer: (B)

2. Let 

and

Then A ∩ B is :

(A)  A portion of a circle centred at (0, −1/√3 that lies in the second and third quadrants only

(B)  a portion of a circle centred at (0, −1/√3) that lies in the second quadrant only

(C)  an empty set

(D)  a portion of a circle of radius 2/√3 that lies in the third quadrant only

Answer: (B)

3. Let A be a 3 × 3 invertible matrix. If |adj (24A)| = |adj (3 adj (2A))|, then |A|2 is equal to :

(A)  66

(B)  212

(C)  26

(D)  1

Answer: (C)

4. The ordered pair (a, b), for which the system of linear equations

3x – 2y + z = b 

5x – 8y + 9z = 3 

2x + y + az = –1 

has no solution, is :

(A)  (3, 1/3)

(B)  (−3, 1/3)

(C)  (−3, −1/3)

(D)  (3, −1/3)

Answer: (C)

5. The remainder when (2021)2023 is divided by 7 is :

(A)  1

(B)  2

(C)  5

(D)  6

Answer: (C)

6. is equal to:

(A)  √2

(B)  −√2

(C)  1/√2

(D)  −1/√2

Answer: (D)

7. g : R → R be two real valued functions defined as  where k1 and k2 are real constants. If (goƒ) is differentiable at x = 0, then (goƒ) (–4) + (goƒ) (4) is equal to :

(A)  4(e4 + 1)

(B)  2(2e4 + 1)

(C)  4e4

(D)  2(2e4 – 1)

Answer: (D)

8. The sum of the absolute minimum and the absolute maximum values of the function ƒ(x) = |3x – x2 + 2| – x in the interval [–1, 2] is :

Answer: (A)

9. Let S be the set of all the natural numbers, for which the line  is a tangent to the curve  at the point (a, b), ab ≠ 0. Then :

(A) S = ɸ

(B) n(S) = 1

(C) S = {2k : k ∈ N }

(D) S = N

Answer: (D)

10. The area bounded by the curve y = |x2 – 9| and the line y = 3 is

(A)  4(2√3 + √6 – 4)

(B)  4(4√3 + √6 – 4)

(C)  8(4√3 + 3√6 – 9)

(D)  8(4√3 + √6 – 9)

Answer: (*)

11. Let R be the point (3, 7) and let P and Q be two points on the line x + y = 5 such that PQR is an equilateral triangle, Then the area of ΔPQR is :

(A)  25/4√3

(B)  25√3/2

(C)  25/√3

(D)  25/2√3

Answer: (D)

12. Let C be a circle passing through the points A(2, –1) and B (3, 4). The line segment AB is not a diameter of C. If r is the radius of C and its centre lies on the circle (x – 5)2 + (y – 1)2 = 13/2, then r2 is equal to :

(A)  32

(B)  65/2

(C)  61/2

(D)  30

Answer: (B)

13. Let the normal at the point P on the parabola y2 = 6x pass through the point (5, –8). If the tangent at P to the parabola intersects its directrix at the point Q, then the ordinate of the point Q is :

(A)  −3

(B)  −9/4

(C)  −5/2

(D)  −2

Answer: (B)

14. If the two lines  z = 2 and  perpendicular, then an angle between the lines l­2 and  is :

(A)  cos1(29/4)

(B)  sec1(29/4)

(C)  cos1(2/29)

(D)  cos1(2/√29)

Answer: (B)

15. Let the plane 2x + 3y + z + 20 = 0 be rotated through a right angle about its line of intersection with the plane x – 3y + 5z = 8. If the mirror image of the point (2, −1/2, 2) in the rotated plane is B( a, b, c), then :

Answer: (A)

16. If  then the value of  is :

Answer: (A)

17. Let a biased coin be tossed 5 times. If the probability of getting 4 heads is equal to the probability of getting 5 heads, then the probability of getting atmost two heads is:

(A)  275/65

(B)  36/54

(C)  181/55

(D)  46/64

Answer: (D)

18. The mean of the numbers a, b, 8, 5, 10 is 6 and their variance is 6.8. If M is the mean deviation of the numbers about the mean, then 25 M is equal to:

(A)  60

(B)  55

(C)  50

(D)  45

Answer: (A)

19. Let f(x) = 2cos−1 x + 4 cot−1 x – 3x2 – 2x + 10, x ∈ [−1, 1]. If [a, b] is the range of the function then 4a – b is equal to :

(A)  11

(B)  11 – π

(C)  11 + π

(D)  15 – π

Answer: (B)

20. Let, ∆, ∇ ∈ {⋀, ⋁} be such that p ∇ q ⇒ ((p ∆ q) ∇ r) is a tautology. Then (p ∇ q) ∆ r) is logically equivalent to :

(A)  (p ∆ q) ⋁ q

(B)  (p ∆ r) ⋀ q

(C)  (p ⋀ r) ∆ q

(D)  (p ∇ r) ⋀ q)

Answer: (A)

SECTION-B

21. The sum of the cubes of all the roots of the equation x4 – 3x3 –2x2 + 3x +1 = 0 is _______.

Answer: (36)

22. There are ten boys B1, B2, …, B10 and five girls G1, G2,…, G5 in a class. Then the number of ways of forming a group consisting of three boys and three girls, if both B1 and B2 together should not be the members of a group, is ________.

Answer: (1120)

23. Let the common tangents to the curves 4(x2 + y2) = 9 and y2 = 4x intersect at the point Q. Let an ellipse, centered at the origin O, has lengths of semi-minor and semi-major axes equal to OQ and 6, respectively. If e and I respectively denote the eccentricity and the length of the latus rectum of this ellipse, then l/e2 is equal to ________.

Answer: (4)

24. Let f(x) = max{|x + 1|, |x + 2|, …, |x + 5|}. Then  is equal to __________.

Answer: (21)

25. Let the solution curve y = y(x) of the differential equation (4 + x2)dy – 2x(x2 + 3y + 4)dx = 0 pass through the origin. Then y(2) is equal to________.

Answer: (12)

26. If sin2(10°)sin(20°)sin(40°)sin(50°)sin(70°) =  then 16 + α1 is equal to _______.

Answer: (80)

27. Let A = {n ∈ N : H.C.F. (n, 45) = 1} and Let B = {2k : k ∈ {1, 2, …, 100}}. Then the sum of all the elements of A ∩ B is __________.

 

Answer: (5264)

28. The value of the integral  is equal to ________.

Answer: (6)

29. Let  and  Then A + B is equal to ________.

Answer: (1100)

30. Let Let y = y(x), x ∈ S, be the solution curve of the differential equation  If the sum of abscissas of all the points of intersection of the curve y = y(x) with the curve  then k is equal to ___________.

Answer: (42)

JEE Main Session 1 25th June 2022 Shift-1 Question Paper and Answer Key

JEE Main 2022 Session 1 25th June 2022 Shift-1

IMPORTANT INSTRUCTIONS:

(1) The test is of 3 hours duration:

(2) The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i) Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and 1 mark for wrong answer.

(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and −1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

PHYSICS

Section-A

1. If  then the relative error in Z will be :

Answer: (C)

2.  is a vector quantity such that  Which of the following expressions is true for

Answer: (C)

3. Which of the following relations is true for two unit vector  making an angle θ to each other?

Answer: (B)

4. If force  acts on a particle having position vector  then, the torque about the origin will be :-

Answer: (B)

5. The height of any point P above the surface of earth is equal to diameter of earth. The value of acceleration due to gravity at point P will be (Given g = acceleration due to gravity at the surface of earth).

(A)  g/2

(B)  g/4

(C)  g/3

(D)  g/9

Answer: (D)

6. The terminal velocity (vt) of the spherical rain drop depends on the radius (r) of the spherical rain drop as

(A)  r1/2

(B)  r

(C)  r2

(D)  r3

Answer: (C)

7. The relation between root mean square speed (vrms) and most probable speed (vp) for the molar mass M of oxygen gas molecule at the temperature of 300 K will be

Answer: (B)

8. In the figure, a very large plane sheet of positive charge is shown. P1 and P2 are two points at distance l and 2l from the charge distribution. If σ is the surface charge density, then the magnitude of electric fields E1 and E2 and P1 and P2 respectively are

(A)  E1 = σ/ε0, E2 = σ/2ε0

(B)  E1 = 2σ/ε0, E2 = σ/ε0

(C)  E1 = E2 = σ/2ε0

(D)  E1 = E2 = σ/ε0

Answer: (C)

9. Match List-I with List-II

Choose the correct answer from the options given below:-

(A) (A) – (II), (B) – (I), (C) – (IV), (D) – (III)

(B) (A) – (II), (B) – (I), (C) – (III), (D) – (IV)

(C) (A) – (III), (B) – (IV), (C) – (II), (D) – (I)

(D) (A) – (III), (B) – (I), (C) – (II), (D) – (IV)

Answer: (A)

10. A long straight wire with a circular cross-section having radius R, is carrying a steady current I. The current I is uniformly distributed across this cross-section. Then the variation of magnetic field due to current I with distance r (r < R) from its centre will be

(A)  B ∝ r2

(B)  B ∝ r

(C)  B ∝ 1/r2

(D)  B ∝ 1/r

Answer: (B)

11. If wattless current flows in the AC circuit, then the circuit is :

(A) Purely Resistive circuit

(B) Purely Inductive circuit

(C) LCR series circuit

(D) RC series circuit only

Answer: (B)

12. The electric field in an electromagnetic wave is given by E = 56.5 sinω(t – x/c) NC–1. Find the intensity of the wave if it is propagating along x-axis in the free space.

(Given ∈0 = 8.85 × 10–12C2N–1m–2)

(A)  5.65 Wm–2

(B)  4.24 Wm–2

(C)  1.9 × 10–7 Wm–2

(D)  56.5 Wm–2

Answer: (B)

13. The two light beams having intensities I and 9I interfere to produce a fringe pattern on a screen. The phase difference between the beams is π/2 at point P and π at point Q. Then the difference between the resultant intensities at P and Q will be:

(A)  2 I

(B)  6 I

(C)  5 I

(D)  7 I

Answer: (B)

14. A light wave travelling linearly in a medium of dielectric constant 4, incidents on the horizontal interface separating medium with air. The angle of incidence for which the total intensity of incident wave will be reflected back into the same medium will be :

(Given : relative permeability of medium μr= 1)

(A)  10°

(B)  20°

(C)  30°

(D)  60°

Answer: (D)

15. Given below are two statements :

Statement I: Davisson-Germer experiment establishes the wave nature of electrons.

Statement II: If electrons have wave nature, they can interfere and show diffraction.

In the light of the above statements choose the correct answer from the option given below :

(A) Both statement I and statement II are true.

(B) Both statement I and statement II are false.

(C) Statement I is true but statement II is false.

(D) Statement I is false but statement II is true.

Answer: (A)

16. The ratio for the speed of the electron in the 3rd orbit of He+ to the speed of the electron in the 3rd orbit of hydrogen atom will be :

(A)  1 : 1

(B)  1 : 2  

(C)  4 : 1

(D)  2 : 1

Answer: (D)

17. The photodiode is used to detect the optical signals. These diodes are preferably operated in reverse biased mode because :

(A) fractional change in majority carriers produce higher forward bias current

(B) fractional change in majority carriers produce higher reverse bias current

(C) fractional change in minority carriers produce higher forward bias current

(D) fractional change in minority carriers produce higher reverse bias current

Answer: (D)

18. A signal of 100 THz frequency can be transmitted with maximum efficiency by :

(A) Coaxial cable

(B) Optical fibre

(C) Twisted pair of copper wires

(D) Water

Answer: (B)

19. The difference of speed of light in the two media A and B(vA – vB) is 2.6 × 107 m/s. If the refractive index of medium B is 1.47, then the ratio of refractive index of medium B to medium A is: (Given: speed of light in vacuum C = 3 × 108ms–1)

(A)  1.303

(B)  1.318

(C)  1.13

(D)  0.12

Answer: (C)

20. A teacher in his physics laboratory allotted an experiment to determine the resistance (G) of a galvanometer. Students took the observations for 1/3 deflection in the galvanometer. Which of the below is true for measuring value of G?

(A)  1/3 deflection method cannot be used for determining the resistance of the galvanometer.

(B)  1/3 deflection method can be used and in this case the G equals to twice the value of shunt resistance(s)

(C)  1/3 deflection method can be used and in this case, the G equals to three times the value of shunt resistance(s)

(D)  1/3 deflection method can be used and in this case the G value equals to the shunt resistance(s)

Answer: (B)

SECTION-B

21. A uniform chain of 6 m length is placed on a table such that a part of its length is hanging over the edge of the table. The system is at rest. The co-efficient of static friction between the chain and the surface of the table is 0.5, the maximum length of the chain hanging from the table is __________m.

Answer: (2)

22. A 0.5 kg block moving at a speed of 12 ms–1 compresses a spring through a distance 30 cm when its speed is halved. The spring constant of the spring will be ___ Nm–1.

Answer: (600)

23. The velocity of upper layer of water in a river is 36 kmh–1. Shearing stress between horizontal layers of water is 10–3 Nm–2. Depth of the river is _____________ m. (Co-efficient of viscosity of water is 10–2s)

Answer: (100)

24. A steam engine intakes 50 g of steam at 100°C per minute and cools it down to 20°C. If latent heat of vaporization of steam is 540 cal g–1, then the heat rejected by the steam engine per minute is ___________ × 103

(Given : specific heat capacity of water : 1 cal g–1 °C–1)

Answer: (31)

25. The first overtone frequency of an open organ pipe is equal to the fundamental frequency of a closed organ pipe. If the length of the closed organ pipe is 20 cm. The length of the open organ pipe is __________ cm.

Answer: (80)

26. The equivalent capacitance between points A and B in below shown figure will be _______μF.

Answer: (6)

27. A resistor develops 300 J of thermal energy in 15 s, when a current of 2 A is passed through it. If the current increases to 3 A, the energy developed in 10 s is _______ J.

Answer: (450)

28. The total current supplied to the circuit as shown in figure by the 5 V battery is _________A.

Answer: (2)

29. The current in a coil of self-inductance 2.0 H is increasing according to I = 2sin(t2)A. The amount of energy spent during the period when current changes from 0 to 2A is _______ J.

Answer: (4)

30. A force on an object of mass 100 g is  The position of that object at t = 2s is  after starting from rest. The value of a/b will be _________

Answer: (2)

CHEMISTRY

SECTION-A

1. Bonding in which of the following diatomic molecule(s) become(s) stronger, on the basis of MO Theory, by removal of an electron?

(A) NO

(B) N2

(C) O2

(D) C2

(E) B2

Choose the most appropriate answer from the options given below :

(A) (A), (B), (C) only

(B) (B), (C), (E) only

(C) (A), (C) only

(D) (D) only

Answer: (C)

2. Incorrect statement for Tyndall effect is :

(A) The refractive indices of the dispersed phase and the dispersion medium differ greatly in magnitude.

(B) The diameter of the dispersed particles is much smaller than the wavelength of the light used.

(C) During projection of movies in the cinemas hall, Tyndall effect is noticed.

(D) It is used to distinguish a true solution from a colloidal solution.

Answer: (B)

3. The pair, in which ions are isoelectronic with Al3+ is:

(A) Br and Be2+

(B) Cl and Li+

(C) S2– and K+

(D) O2– and Mg2+

Answer: (D)

4. Leaching of gold with dilute aqueous solution of NaCN in presence of oxygen gives complex [A], which on reaction with zinc forms the elemental gold and another complex [B]. [A] and [B], respectively are :

(A) [Au(CN)4] and [Zn(CN)2 (OH)2]2−

(B) [Au(CN)2] and [Zn (OH)4]2−

(C) [Au(CN)2] and [Zn (CN)4]2−

(D) [Au(CN)4]2− and [Zn (CN)6]4−

Answer: (C)

5. Number of electron deficient molecules among the following PH3, B2H6, CCl4, NH3, LiH and BCl3 is

(A)  0

(B)  1

(C)  2

(D)  3

Answer: (C)

6. Which one of the following alkaline earth metal ions has the highest ionic mobility in its aqueous solution?

(A)  Be2+

(B)  Mg2+

(C)  Ca2+

(D)  Sr2+

Answer: (D)

7. White precipitate of AgCI dissolves in aqueous ammonia solution due to formation of:

(A)  [Ag(NH3)4]CI2

(B)  [Ag(CI)2(NH3)2]

(C)  [Ag(NH3)2]CI

(D)  [Ag(NH3)CI]CI

Answer: (C)

8. Cerium (IV) has a noble gas configuration. Which of the following is correct statement about it?

(A) It will not prefer to undergo redox reactions.

(B) It will prefer to gain electron and act as an oxidizing agent

(C) It will prefer to give away an electron and behave as reducing agent

(D) It acts as both, oxidizing and reducing agent.

Answer: (B)

9. Among the following which is the strongest oxidizing agent?

(A)  Mn3+

(B)  Fe3+

(C)  Ti3+

(D)  Cr3+

Answer: (A)

10. The eutrophication of water body results in:

(A) loss of Biodiversity.

(B) breakdown of organic matter.

(C) increase in biodiversity.

(D) decrease in BOD.

Answer: (A)

11. Phenol on reaction with dilute nitric acid, gives two products. Which method will be most efficient for large scale separation?

(A) Chromatographic separation

(B) Fractional crystallisation

(C) Steam distillation

(D) Sublimation

Answer: (C)

12. In the following structures, which one is having staggered conformation with maximum dihedral angle?

Answer: (C)

13. The products formed in the following reaction.

Answer: (B)

14. The IUPAC name of ethylidene chloride is:

(A) 1-Chloroethene

(B) 1-Chloroethyne

(C) 1, 2-Dichloroethane

(D) 1, 1-Dichloroethane

Answer: (D)

15. The major product in the reaction

(A) t-Butyl ethyl ether

(B) 2, 2-Dimethyl butane

(C) 2-Methyl pent-1-ene

(D) 2-Methyl prop-1-ene

Answer: (D)

16. The intermediate X, in the reaction :

Answer: (C)

17. In the following reaction:

The compound A and B respectively are:

Answer: (C)

18. The reaction of with bromine and KOH gives RNH2 as the end product. Which one of the following is the intermediate product formed in this reaction?

Answer: (C)

19. Using very little soap while washing clothes, does not serve the purpose of cleaning of clothes, because:

(A) soap particles remain floating in water as ions.

(B) the hydrophobic part of soap is not able to take away grease.

(C) the micelles are not formed due to concentration of soap, below its CMC value.

(D) colloidal structure of soap in water is completely distributed.

Answer: (C)

20. Which one of the following is an example of artificial sweetner?

(A)  Bithional

(B)  Alitame

(C)  Salvarsan

(D)  Lactose

Answer: (B)

SECTION-B

21. The number of N atoms in 681 g of C7H5N3O6 is x × 1021. The value of x is ______. (NA = 6.02 × 1023 mol–1) (Nearest Integer)

Answer: (5418)

22. The distance between Na+ and Cl ions in solid NaCl of density 43.1 g cm–3 is ____ × 10–10 (Nearest Integer)

(Given : NA = 6.02 × 1023 mol–1)

Answer: (1)

23. The longest wavelength of light that can be used for the ionisation of lithium atom (Li) in its ground state is x × 10–8 The value of x is ______. (Nearest Integer)

(Given : Energy of the electron in the first shell of the hydrogen atom is –2.2 x 10–18 J;

h = 6.63 × 10–34 Js and c = 3 × 108 ms–1)

Answer: (4)

24. The standard entropy change for the reaction 4Fe(s) + 3O2(g) 2Fe2O3(s) is –550 J K–1 at 298 K.

[Given: The standard enthalpy change for the reaction is –165 kJ mol–1]. The temperature in K at which the reaction attains equilibrium is ________. (Nearest Integer)

Answer: (300)

25. 1 L aqueous solution of H2SO4 contains 0.02 m mol H2SO4. 50% of this solution is diluted with deionized water to give 1 L solution (A). In solution (A), 0.01 m mol of H2SO4 are added. Total m mols of H2SO4 in the final solution is ______ × 103 m mols.

Answer: (0)

26. The standard free energy change (ΔG°) for 50% dissociation of N2O4 into NO2 at 27°C and 1 atm pressure is –x J mol–1. The value of x is _____. (Nearest Integer)

[Given : R = 8.31 J K–1 mol–1, log 1.33 = 0.1239 ln 10 = 2.3]

Answer: (710)

27. In a cell, the following reactions take place

The standard electrode potential for the spontaneous reaction in the cell is x × 10–2 V at 208 K. The value of x is _______. (Nearest Integer)

Answer: (23)

28. For a given chemical reaction

γ1A + γ2B → γ3C + γ4D

Concentration of C changes from 10 mmol dm–3 to 20 mmol dm–3 in 10 seconds. Rate of appearance of D is 1.5 times the rate of disappearance of B which is twice the rate of disappearance A. The rate of appearance of D has been experimentally determined to be 9 mmol dm–3 s–1. Therefore, the rate of reaction is _____ mmol dm–3 s–1.

Answer: (1)

29. If [Cu(H2O)4]2+ absorbs a light of wavelength 600 nm for d-d transition, then the value of octahedral crystal field splitting energy for [Cu(H2O)6]2+ will be _______ ×10–21 [Nearest integer]

(Given : h = 6.63 × 10–34 Js and c = 3.08 × 108 ms–1)

Answer: (765)

30. Number of grams of bromine that will completely react with 5.0 g of pent-1-ene is ______ × 10–2 (Atomic mass of Br = 80 g/mol) [Nearest integer]

Answer: (1143)

MATHEMATICS

SECTION-A

1. Let a circle C touch the lines L1 : 4x – 3y +K1 = 0 and L2 : 4x – 3y + K2 = 0, K1, K2 ∈ If a line passing through the centre of the circle C intersects L1 at (–1, 2) and L2 at (3, –6), then the equation of the circle C is :

(A) (x – 1)2 + (y – 2)2 = 4

(B) (x + 1)2 + (y – 2)2 = 4

(C) (x – 1)2 + (y + 2)2 = 16

(D) (x – 1)2 + (y – 2)2 = 16

Answer: (C)

2. The value of  is equal to

(A)  π2/4

(B)  π2/2

(C)  π/4

(D)  π/2

Answer: (C)

3. Let a, b and c be the length of sides of a triangle ABC such that  If r and R are the radius of incircle and radius of circumcircle of the triangle ABC, respectively, then the value of R/r is equal to

(A)  5/2

(B)  2

(C)  3/2

(D)  1

Answer: (A)

4. Let f : N→R be a function such that f(x + y) = 2f(x) f(y) for natural numbers x and y. If f(1) = 2, then the value of α for which  holds, is

(A)  2

(B)  3

(C)  4

(D)  6

Answer: (C)

5. Let A be a 3 × 3 real matrix such that  and  If X = (x1, x2, x3)T and I is an identity matrix of order 3, then the system  has

(A) No solution

(B) Infinitely many solutions

(C) Unique solution

(D) Exactly two solutions

Answer: (B)

6. Let f : R→R be defined as f(x) = x3 + x – 5 If g(x) is a function such that f(g(x)) = x, ∀ x ∈ R, then g′ (63) is equal to _______.

(A)  1/49

(B)  3/49

(C)  43/49

(D)  91/49

Answer: (A)

7. Consider the following two propositions :

P1 : ~ (p → ~ q)

P2: (p ∧ ~q) ∧ ((-~p) ∨ q)

If the proposition p → ((~p) ∨ q) is evaluated as FALSE, then :

(A) P1 is TRUE and P2 is FALSE

(B) P1 is FALSE and P2 is TRUE

(C) Both P1 and P2 are FALSE

(D) Both P1 and P2 are TRUE

Answer: (C)

8. If  then the remainder when K is divided by 6 is

(A)  1

(B)  2

(C)  3

(D)  5

Answer: (D)

9. Let f(x) be a polynomial function such that f(x) + f′(x) + f′′(x) = x5 + 64. Then, the value of 

(A)  −15

(B)  −60

(C)  60

(D)  15

Answer: (A)

10. Let E1 and E2 be two events such that the conditional probabilities P(E1|E2) = 1/2, P(E2|E1) = 3/4 and P(E1∩E2) = 1/8. Then:

(A)  P(E1 ∩ E2) = P(E1) ∙ P(E2)

(B)  P(E’1 ∩ E’2) = P(E’1) ∙ P(E2)

(C)  P(E1 ∩ E’2) = P(E1) ∙ P(E2)

(D)  P(E’1 ∩ E2) = P(E1) ∙ P(E2)

Answer: (C)

11. Let  If M and N are two matrices given by  then MN2 is

(A) a non-identity symmetric matrix

(B) a skew-symmetric matrix

(C) neither symmetric nor skew-symmetric matrix

(D) an identity matrix

Answer: (A)

12. Let g : (0, ∞) → R be a differentiable function such that  for all x > 0, where c is an arbitrary constant. Then.

(A)  g is decreasing in (0, π/4)

(B)  g’ is increasing in (0, π/4)

(C)  g + g’ is increasing in (0, π/2)

(D)  g – g’ is increasing in (0, π/2)

Answer: (D)

13. Let f :R→R and g : R → R be two functions defined by f(x) = loge(x2 + 1) – e–x + 1 and  Then, for which of the following range of α, the inequality  holds?

(A) (2, 3)

(B) (–2, –1)

(C) (1, 2)

(D) (–1, 1)

Answer: (A)

14. Let  ai > 0, i = 1, 2, 3 be a vector which makes equal angles with the coordinate axes OX, OY and OZ. Also, let the projection of  on the vector  be 7. Let  be a vector obtained by rotating with 90°. If  and x-axis are coplanar, then projection of a vector  is equal to

(A)  √7

(B)  √2

(C)  2

(D)  7

Answer: (B)

15. Let y = y(x) be the solution of the differential equation (x + 1)y′ – y = e3x(x + 1)2, with y(0) = 1/3. Then, the point x = −4/3 for the curve y = y(x) is:

(A) not a critical point

(B) a point of local minima

(C) a point of local maxima

(D) a point of inflection

Answer: (B)

16. If y = m1x + c1 and y = m2x + c2, m1 ≠ m2 are two common tangents of circle x2 + y2 = 2 and parabola y2 = x, then the value of 8|m1m2| is equal to :

(A)  3 + 4√2

(B)  −5 + 6√2

(C)  −4 + 3√2

(D)  7 + 6√2

Answer: (C)

17. Let Q be the mirror image of the point P(1, 0, 1) with respect to the plane S: x + y + z = 5. If a line L passing through (1, –1, –1), parallel to the line PQ meets the plane S at R, then QR2 is equal to :

(A)  2

(B)  5

(C)  7

(D)  11

Answer: (B)

18. If the solution curve y = y(x) of the differential equation y2dx + (x2 – xy + y2)dy = 0, which passes through the point (1,1) and intersects the line y = √3 x at the point (α, √3α), then value of loge(√3α) is equal to

(A)  π/3

(B)  π/2

(C)  π/12

(D)  π/6

Answer: (C)

19. Let x = 2t, y = t2/3 be a conic. Let S be a conic. Let S be the focus and B be the point on the axis of the conic such that SA⊥BA, where A is any point on the conic. If k is the ordinate of the centroid of the ΔSAB, then  equal to

(A)  17/18

(B)  19/18

(C)  11/18

(D)  13/18

Answer: (D)

20. Let a circle C in complex plane pass through the points z1 = 3 + 4i, z2 = 4 + 3i and z3 = 5i. If z(≠ z1) is a point on C such that the line through z and z1 is perpendicular to the line through z2 and z3, then arg(z) is equal to:

Answer: (B)

SECTION-B

21. Let Cr denote the binomial coefficient of xr in the expansion of (1 + x)10. If for α, β ∈ R, C1 + 3⋅2 C2 + 5⋅3 C3 + … upto 10 terms  then the value of α + β is equal to _____

Answer: (286*)

22. The number of 3-digit odd numbers, whose sum of digits is a multiple of 7, is ________.

Answer: (63)

23. Let θ be the angle between the vectors  where  Then  is equal to _________

Answer: (576)

24. Let the abscissae of the two points P and Q be the roots of 2x2 – rx + p = 0 and the ordinates of P and Q be the roots of x2 – sx – q = 0. If the equation of the circle described on PQ as diameter is 2(x2 + y2) – 11x – 14y – 22 = 0, then 2r + s – 2q + p is equal to _________.

Answer: (7)

25. The number of values of x in the interval  for which 14cosec2x – 2 sin2x = 21 – 4 cos2x holds, is ___________.

Answer: (4)

26. For a natural number n, let an = 19n – 12n. Then, the value of  is

Answer: (4)

27. Let f : R → R be a function defined by  If the function g(x) = f (f (f (x))) + f (f (x)), then the greatest integer less than or equal to g(1) is ___________.

Answer: (2)

28. Let the lines

intersect at the point S. If a plane ax + by – z + d = 0 passes through S and is parallel to both the lines L1 and L2, then the value of a + b + d is equal to _______.

Answer: (5)

29. Let A be a 3 × 3 matrix having entries from the set {–1, 0, 1}. The number of all such matrices A having sum of all the entries equal to 5, is ____________.

Answer: (414)

30. The greatest integer less than or equal to the sum of first 100 terms of the sequence 1/3, 5/9, 19/27, 65/81, … is equal to ________.

Answer: (98)

JEE Main Session 1 24th June 2022 Shift 1 Question Paper and Answer Key

JEE Main 2022 Session 1 June 24 Shift 1

IMPORTANT INSTRUCTIONS:

(1) The test is of 3 hours duration:

(2) The Test Booklet consists of 90 questions. The maximum marks are 300.

(3) There are three parts in the question paper consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each part (subject) has two sections.

(i) Section-A: This section contains 20 multiple choice questions which have only one correct answer. each question carries 4 marks for correct answer and 1 mark for wrong answer.

(ii) Section-B: This section contains 10 questions. In Section-B, attempt any five questions out of 10. The answer to each of the questions is a numerical value. Each question carries 4 marks for correct answer and 1 mark for wrong answer. For Section-B, the answer should be rounded off to the nearest integer.

PHYSICS

SECTION-A

1. The bulk modulus of a liquid is 3 × 1010 Nm2. The pressure required to reduce the volume of liquid by 2% is :

(A)  3 × 108 Nm2

(B)  9 × 108 Nm2

(C)  6 × 108 Nm2

(D)  12 × 108 Nm2

Answer: (C)

2. Given below are two statements : One is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : In an uniform magnetic field, speed and energy remains the same for a moving charged particle.

Reason (R) : Moving charged particle experiences magnetic force perpendicular to its direction of motion.

(A)  Both (A) and (R) are true and (R) is the correct explanation of (A)

(B)  Both (A) and (R) are true but (R) is NOT the correct explanation of (A)

(C)  (A) is true but (R) is false

(D)  (A) is false but (R) is true.

Answer: (A)

3. Two identical cells each of emf 1.5 V are connected in parallel across a parallel combination of two resistors each of resistance 20Ω. A voltmeter connected in the circuit measures 1.2 V. The internal resistance of each cell is

(A)  2.5Ω

(B)  4Ω

(C)  5Ω

(D)  10Ω

Answer: (C)

4. Identify the pair of physical quantities which have different dimensions :

(A)  Wave number and Rydberg’s constant

(B)  Stress and Coefficient of elasticity

(C)  Coercivity and Magnetisation

(D)  Specific heat capacity and Latent heat 

Answer: (D)

5. A projectile is projected with velocity of 25 m/s at an angle θ with the horizontal. After t seconds its inclination with horizontal becomes zero. If R represents horizontal range of the projectile, the value of θ will be : [use g = 10 m/s2]

Answer: (D)

6. A block of mass 10 kg starts sliding on a surface with an initial velocity of 9.8 ms1. The coefficient of friction between the surface and bock is 0.5. The distance covered by the block before coming to rest is : [use g = 9.8 ms2]

(A)  4.9 m

(B)  9.8 m

(C)  12.5 m

(D)  19.6 m

Answer: (B)

7. A boy ties a stone of mass 100 g to the end of a 2 m long string and whirls it around in a horizontal plane. The string can withstand the maximum tension of 80 N. If the maximum speed with which the stone can revolve is  A boy ties a stone of mass 100 g to the end of a 2 m long string and whirls it around in a horizontal plane. The string can withstand the maximum tension of 80 N. If the maximum speed with which the stone can revolve is

(A)  400

(B)  300

(C)  600

(D)  800

Answer: (C)

8. A vertical electric field of magnitude 4.9 × 105 N/C just prevents a water droplet of a mass 0.1 g from falling. The value of charge on the droplet will be : (Given g = 9.8 m/s2)

(A)  1.6 × 109 C

(B)  2.0 × 109 C

(C)  3.2 × 109 C

(D)  0.5 × 109 C

Answer: (B)

9. A particle experiences a variable force  in a horizontal x-y plane. Assume distance in meters and force is newton. If the particle moves from point (1, 2) to point (2, 3) in the x-y plane, the Kinetic Energy changes by

(A)  50.0 J

(B)  12.5 J

(C)  25.0 J

(D)  0 J

Answer: (C)

10. The approximate height from the surface of earth at which the weight of the body becomes 1/3 of its weight on the surface of earth is : [Radius of earth R = 6400 km and √3 = 1.732]

(A)  3840 km

(B)  4685 km

(C)  2133 km

(D)  4267 km

Answer: (B)

11. A resistance of 40 Ω is connected to a source of alternating current rated 220 V, 50 Hz. Find the time taken by the current to change from its maximum value to rms value :

(A)  2.5 ms

(B)  1.25 ms

(C)  2.5 s

(D)  0.25 s

Answer: (A)

12. The equations of two waves are given by :

y1 = 5 sin2π(x – vt) cm

y2 = 3sin2π(x – vt + 1.5)cm

These waves are simultaneously passing through a string. The amplitude of the resulting wave is

(A)  2 cm

(B)  4 cm

(C)  5.8 cm

(D)  8 cm

Answer: (A)

13. A plane electromagnetic wave travels in a medium of relative permeability 1.61 and relative permittivity 6.44. If magnitude of magnetic intensity is 4.5 × 10−2 Am−1 at a point, what will be the approximate magnitude of electric field intensity at that point ?

(Given : permeability of free space μ0 = 4π × 10−7 NA−2, speed of light in vacuum c = 3 × 108 ms−1)

(A)  16.96 Vm−1

(B)  2.25 × 10−2 Vm−1

(C)  8.48 Vm−1

(D)  6.75 × 106 Vm−1

Answer: (C)

14. Choose the correct option from the following options given below :

(A)  In the ground state of Rutherford’s model electrons are in stable equilibrium. While in Thomson’s model electrons always experience a net-force.

(B)  In the ground state of Rutherford’s model electrons are in stable equilibrium. While in Thomson’s model electrons always experience a net-force.

(C)  A classical atom based on Rutherford’s model is doomed to collapse.

(D)  The positively charged part of the atom possesses most of the mass in Rutherford’s model but not in Thomson’s model.

Answer: (C)

15. Nucleus A is having mass number 220 and its binding energy per nucleon is 5.6 MeV. It splits in two fragments ‘B’ and ‘C’ of mass numbers 105 and 115. The binding energy of nucleons in ‘B’ and ‘C’ is 6.4 MeV per nucleon. The energy Q released per fission will be :

(A)  0.8 MeV

(B)  275 MeV

(C)  220 MeV

(D)  176 MeV

Answer: (D)

16. A baseband signal of 3.5 MHz frequency is modulated with a carrier signal of 3.5 GHz frequency using amplitude modulation method. What should be the minimum size of antenna required to transmit the modulated signal ?

(A)  42.8 m

(B)  42.8 mm

(C)  21.4 mm

(D)  21.4 m

Answer: (C)

17. A Carnot engine whose heat sinks at 27°C, has an efficiency of 25%. By how many degrees should the temperature of the source be changed to increase the efficiency by 100% of the original efficiency ?

(A)  Increases by 18°C

(B)  Increase by 200°C

(C)  Increase by 120°C

(D)  Increase by 73°

Answer: (B)

18. A parallel plate capacitor is formed by two plates each of area 30π cm2 separated by 1 mm. A material of dielectric strength 3.6 × 107 Vm−1 is filled between the plates. If the maximum charge that can be stored on the capacitor without causing any dielectric breakdown is 7 × 10−6 C, the value of dielectric constant of the material is :

(A)  1.66

(B)  1.75

(C)  2.25

(D)  2.33

Answer: (D)

19. The magnetic field at the centre of a circular coil of radius r, due to current I flowing through it, is B. The magnetic field at a point along the axis at a distance r/2 from the centre is :

(A)  B/2

(B)  2B

(C) 

(D) 

Answer: (C)

20. Two metallic blocks M1 and M2 of same area of cross-section are connected to each other (as shown in figure). If the thermal conductivity of M2 is K then the thermal conductivity of M1 will be : [Assume steady state heat conduction]

(A)  10 K

(B)  8 K

(C)  12.5 K

(D)  2 K

Answer: (B)

SECTION-B

21. 056 kg of Nitrogen is enclosed in a vessel at a temperature of 127°C. The amount of heat required to double the speed of its molecules is _____ k cal. (Take R = 2 cal mole−1K−1)

Answer: (12)

22. Two identical thin biconvex lenses of focal length 15 cm and refractive index 1.5 are in contact with each other. The space between the lenses is filled with a liquid of refractive index 1.25. The focal length of the combination is ______ cm.

Answer: (10)

23. A transistor is used in common-emitter mode in an amplifier circuit. When a signal of 10 mV is added to the base-emitter voltage, the base current changes by 10 μA and the collector current changes by 1.5 mA. The load resistance is 5 kΩ. The voltage gain of the transistor will be _____ .

Answer: (750)

24. As shown in the figure an inductor of inductance 200 mH is connected to an AC source of emf 220 V and frequency 50 Hz. The instantaneous voltage of the source is 0 V when the peak value of current is  The value of a is ______.

Answer: (242)

25. Sodium light of wavelengths 650 nm and 655 nm is used to study diffraction at a single slit of aperture 0.5 mm. The distance between the slit and the screen is 2.0 m. The separation between the positions of the first maxima of diffraction pattern obtained in the two cases is ______ × 10−5

Answer: (3)

26. When light of frequency twice the threshold frequency is incident on the metal plate, the maximum velocity of emitted election is v1. When the frequency of incident radiation is increased to five times the threshold value, the maximum velocity of emitted electron becomes v2. If v2 = x v1, the value of x will be ______.

Answer: (2)

27. From the top of a tower, a ball is thrown vertically upward which reaches the ground in 6 s. A second ball thrown vertically downward from the same position with the same speed reaches the ground in 1.5 s. A third ball released, from the rest from the same location, will reach the ground in ________ s.

Answer: (3)

28. A ball of mass 100 g is dropped from a height h = 10 cm on a platform fixed at the top of vertical spring (as shown in figure). The ball stays on the platform and the platform is depressed by a distance h/2. The spring constant is _______ Nm1. (Use g = 10 ms2)

Answer: (120)

29. In a potentiometer arrangement, a cell gives a balancing point at 75 cm length of wire. This cell is now replaced by another cell of unknown emf. If the ratio of the emf’s of two cells respectively is 3 : 2, the difference in the balancing length of the potentiometer wire in above two cases will be ______ cm.

Answer: (25)

30. A metre scale is balanced on a knife edge at its centre. When two coins, each of mass 10 g are put one on the top of the other at the 10.0 cm mark the scale is found to be balanced at 40.0 cm mark. The mass of the metre scale is found to be x × 102 The value of x is _________.

Answer: (6)

CHEMISTRY

SECTION-A

1. A metre scale is balanced on a knife edge at its centre. When two coins, each of mass 10 g are put one on the top of the other at the 10.0 cm mark the scale is found to be balanced at 40.0 cm mark. The mass of the metre scale is found to be x × 102 The value of x is

(A)  1188 g and 1296 g

(B)  2376 g and 2592 g

(C)  2592 g and 2376 g

(D)  3429 g and 3142 g

Answer: (C)

2. Consider the following pairs of electrons

The pairs of electron present in degenerate orbitals is/are:

(A) Only A

(B) Only B

(C) Only C

(D) (B) and (C)

Answer: (B)

3. Match List-I with List-II

(A)  (A)→(II), (B) → (IV), (C) → (I), (D) → (III)

(B)  (A) → (III), (B) → (IV), (C) → (I), (D) → (II)

(C)  (A) → (III), (B) → (I), (C) → (IV), (D) → (II)

(D)  (A) → (II), (B) → (I), (C) → (IV), (D) → (III)

Answer: (B)

4. For a reaction at equilibrium

the relation between dissociation constant (K), degree of dissociation (α) and equilibrium pressure (p) is given by :

Answer: (B)

5. Given below are two statements :

Statement I : Emulsions of oil in water are unstable       and sometimes they separate into two layers on    standing. 

Statement II :For stabilisation of an emulsion,    excess of electrolyte is added.  In the light of the above statements, choose the    most appropriate answer from the options   given below :

(A)  Both Statement I and Statement II are correct.

(B)  Both Statement I and Statement II are incorrect.

(C)  Statement I is correct but Statement II is incorrect.

(D)  Statement I is incorrect but Statement II is correct.

Answer: (C)

6. Given below are the oxides:

Na2O, AsO3, N2O, NO and Cl­2O7

Number of amphoteric oxides is:

(A)  0

(B)  1

(C)  2

(D)  3

Answer: (B)

7. Match List – I with List – II

Choose the most appropriate answer from the options given below:

(A)  (A) – (IV), (B) – (III), (C) – (II), (D) – (I)

(B)  (A) – (IV), (B) – (I), (C) – (II), (D) – (III)

(C)  (A) –  (II), (B) – (III), (C) – (I), (D) – (IV)

(D)  (A) – (III), (B) – (IV), (C) – (II), (D) – (I)

Answer: (A)

8. The highest industrial consumption of molecular hydrogen is to produce compounds of element:

(A)  Carbon

(B)  Nitrogen

(C)  Oxygen

(D)  Chlorine

Answer: (B)

9. Which of the following statements are correct ?

(A)  Both LiCl and MgCl2 are soluble in ethanol.

(B)  The oxides Li2O and MgO combine with excess of oxygen to give superoxide.

(C)  LiF is less soluble in water than other alkali metal fluorides.

(D)  Li2O is more soluble in water than other alkali metal oxides.

Choose the most appropriate answer from the options given below:

(A) (A) and (C) only

(B)  (A), C) and (D) only

(C) (B) and (C) only

(D) (A) and (C) only

Answer: (A)

10. Identify the correct statement for B2H6 from those given below.

(A) In B2H6, all B-H bonds are equivalent. 

(B) In B2H6 there are four 3-centre-2-electron         bonds. 

(C) B2H6 is a Lewis acid. 

(D) B2H6 can be synthesized form both BF3 and  NaBH4

(E) B2H6 is a planar molecule. 

Choose the most appropriate answer from the options given below :

(A)  (A) and (E) only

(B)  (B), (C) and (E) only

(C)  (C) and (D) only

(D)  (C) and (E) only

Answer: (C)

11. The most stable trihalide of nitrogen is:

(A)  NF3

(B)  NCl3

(C)  NBr3

(D)  NI3

Answer: (A)

12. Which one of the following elemental forms is not present in the enamel of the teeth?

(A)  Ca2+

(B)  P3+

(C)  F

(D)  P5+

Answer: (B)

13. In the given reactions sequence, the major product ‘C’ is :

Answer: (B)

14. Two statements are given below :

Statement I:   The melting point of monocarboxylic acid with even number of carbon atoms  is higher than that of with odd number of carbon atoms acid immediately below and above it in the series.

Statement II :  The solubility of monocarboxylic acids in water decreases with increase in molar mass. 

Choose the most appropriate option:

(A)  Both Statement I and Statement II are correct.

(B)  Both Statement I and Statement II are incorrect.

(C)  Statement I is correct but Statement II is incorrect.

(D)  Statement I is incorrect but Statement II is correct.

Answer: (A)

15. Which of the following is an example of conjugated diketone?

Answer: (C)

16. 

The major product of the above reaction is

Answer: (D)

17. Which of the following is an example of polyester?

(A)  Butadiene-styrene copolymer

(B)  Melamine polymer

(C)  Neoprene

(D)  Poly-β-hydroxybutyrate-co-β-hydroxy valerate

Answer: (D)

18. A polysaccharide ‘X’ on boiling with dil H2SO4 at 393 K under 2-3 atm pressure yields ‘Y’.

‘Y’ on treatment with bromine water gives gluconic acid. ‘X’ contains β-glycosidic linkages only. Compound ‘X’ is :

(A)  starch

(B)  cellulose

(C)  amylose

(D)  amylopectin

Answer: (B)

19. Which of the following is not a broad spectrum antibiotic?

(A)  Vancomycin

(B)  Ampicillin

(C)  Ofloxacin

(D)  Penicillin G

Answer: (D)

20. During the qualitative analysis of salt with cation y2+ , addition of a reagent (X) to alkaline solution of the salt gives a bright red precipitate. The reagent (X) and the cation (y2+) present respectively are:

(A)  Dimethylglyoxime and Ni2+

(B)  Dimethylglyoxime and Co2+

(C)  Nessler‟s reagent and Hg2+

(D)  Nessler‟s reagent and Ni2+

Answer: (A)

SECTION-B

21. Atoms of element X form hcp lattice and those of element Y occupy 2/3 Atoms of element X form hcp lattice and those of element Y occupy ________ (Nearest Integer)

Answer: (43)

22. 2O3(g) ⇌ 3O2(g)

At 300 K, ozone is fifty percent dissociated. The standard free energy change at this  temperature and 1 atm pressure is (–) _______J mol –1 (Nearest integer)  [Given: ln 1.35 = 0.3 and R = 8.3 J K–1 mol–1]

Answer: (747)

23. The osmotic pressure of blood is 7.47 bar at 300 K. To inject glucose to a patient intravenously, it has to be isotonic with blood. The concentration of glucose solution in gL–1 is _______ (Molar mass of glucose = 180 g mol–1 R = 0.083 L bar K–1 mol–1) (Nearest integer)

Answer: (54)

24. The cell potential for the following cell

Pt|H2(g)|H+(aq)||Cu2+(0.01M)|Cu(s)

is 0.576 V at 298 K. The pH of the solution is ___. (Nearest integer)

Answer: (5)

25. The rate constants for decomposition of acetaldehyde have been measured over the temperature range 700 –1000 K. The data has been analysed by plotting In k vs 103/T graph. The value of activation energy for the reaction is___ kJ mol–1. (Nearest integer) (Given : R = 8.31 J K–1 mol–1)

Answer: (154)

26. The difference in oxidation state of chromium in chromate and dichromate salts is _______

Answer: (0)

27. In the cobalt-carbonyl complex: [Co2(CO)8], number of Co-Co bonds is “X” and terminal CO ligands is “Y”. X + Y =______

Answer: (7)

28. A 0.166 g sample of an organic compound was digested with cone. H2SO4 and then distilled with NaOH. The ammonia gas evolved was passed through 50.0 mL of 0.5 N H2SO4. The  used acid required 30.0 mL of 0.25 N NaOH for complete neutralization. The mass percentage  of nitrogen in the organic compound is____.

Answer: (63)

29. Number of electrophilic centre in the given compound is _______

Answer: (3)

30. The major product ‘A’ of the following given reaction has _____ sp2 hybridized carbon atoms. 2,7 – Dimethyl1 – 2, 6 – octadiene 

Answer: (2)

MATHEMATICS

SECTION-A

1. Let A = {z ∈ C : 1 ≤ |z – (1 + i) |≤2 and

B = {z ∈ A : | z – (1 – i) | = 1}. Then, B:

(A)  is an empty set

(B)  contains exactly two elements

(C)  contains exactly three elements

(D)  is an infinite set

Answer: (D)

2. The remainder when 32022 is divided by 5 is

(A)  1

(B)  2

(C)  3

(D)  4

Answer: (D)

3. The surface area of a balloon of spherical shape being inflated, increases at a constant rate. If initially, the radius of balloon is 3 units and after 5 seconds,, it becomes 7 units, then its radius after 9 seconds is :

(A)  9

(B)  10

(C)  11

(D)  12

Answer: (A)

4. Bag A contains 2 white, 1 black and 3 red balls and bag B contains 3 black, 2 red and n white balls. One bag is chosen at random and 2 balls drawn from it at random, are found to be 1 red and 1 black. If the probability that both balls come from Bag A is 6/11, then n is equal to _____ .

(A)  13

(B)  6

(C)  4

(D)  3

Answer: (C)

5. Let x2 + y2 + Ax + By + C = 0 be a circle passing through (0, 6) and touching the parabola y = x2 at (2, 4). Then A + C is equal to______.

(A)  16

(B)  88/5

(C)  72

(D)  −8

Answer: (A)

6. The number of values of α for which the system of equations :

x + y + z = α

x + 2 αy + 3z = −1 

x + 3 αy + 5z = 4 

is inconsistent, is

(A)  0

(B)  1

(C)  2

(D)  3

Answer: (B)

7. If the sum of the squares of the reciprocals of the roots α and β of the equation 3x2 + λx – 1 = 0 is 15, then 6(α3 + β3) is equal to :

(A)  18

(B)  24

(C)  36

(D)  96

Answer: (B)

8. The set of all values of k for which (tan1 x)3 + (cot1 x)3 = kπ3, x ∈ R, is the interval:

Answer: (A)

9. Let S = {√n : 1 ≤ 1 ≤ n ≤ 50 and n is odd}

Let a ∈ S and  

If  then λ is equal to

(A)  218

(B)  221

(C)  663

(D)  1717

Answer: (B)

10. f(x) = 4 loge(x – 1) –2x2 + 4x +5, x > 1, which one of the following is NOT correct ?

(A)  f is increasing in (1, 2) and decreasing in (2, ∞)

(B)  f(x)= –1 has exactly two solutions

(C)  f’(e) –f” (2) < 0

(D)  f(x) = 0 has a root in the interval (e, e +1)

Answer: (C)

11. The tangent at the point (x1, y1) on the curve y = x3 +3x2 + 5 passes through the origin, then  (x1, y1) does NOT lie on the curve :

Answer: (D)

12. The sum of absolute maximum and absolute minimum values of the function f(x) = |2x2 + 3x – 2| + sin x cos x in the interval [0, 1] is:

Answer: (B)

13. If  where n is an even integer , is an arithmetic progression with common difference 1, and  then n is equal to: 

(A)  48

(B)  96

(C)  92

(D)  104

Answer: (B)

14. If x = x(y) is the solution of the differential equation  x (1) = 0; then x(e) is equal to :

(A)  e3(ee – 1)

(B)  ee(e3 – 1)

(C)  e2(ee – 1)

(D)  ee(e2 – 1)

Answer: (A)

15. Let λx – 2y = μ be a tangent to the hyperbola a2x2 – y2 = b2. Then  is equal to :

(A)  −2

(B)  −4

(C)  2

(D)  4

Answer: (D)

16. Let  be unit vectors. If  be a vector such that the angle between  is π/12, and  is equal to

(A)  6(3 – √3)

(B)  3 + √3

(C)  6(3 + √3)

(D)  6(√3 + 1)

Answer: (C)

17. If a random variable X follows the Binomial distribution B (33, p) such that 3P(X = 0) = P(X = 1), then the value of  is equal to

(A)  1320

(B)  1088

(C)  120/1331

(D)  1088/1089

Answer: (A)

18. The domain of the function

Answer: (*)

19. Let  If  then T + n(S) is equal

(A)  7 + √3

(B)  9

(C)  8 + √3

(D)  10

Answer: (B)

20. The number of choices of ∆ ∈ {⋀, ⋁, ⇒, ⟺}, such that (p∆q) ⇒ ((p∆~q) ⋁ ((~p)∆q)) is a tautology, is

(A)  1

(B)  2

(C)  3

(D)  4

Answer: (B)

SECTION-B

21. The number of one-one function f : {a, b, c, d} → {0, 1, 2, … .,10} such that 2f(a) – f(b) + 3f(c) + f(d) = 0 is _____.

Answer: (31)

22. In an examination, there are 5 multiple choice questions with 3 choices, out of which exactly one is correct There are 3 marks for each correct answer, −2 marks for each wrong answer and 0 mark if the question is not attempted. Then, the number of ways a student appearing in the examination gets 5 marks is________.

Answer: (*)

23. Let  be a fixed point in the xy-plane. The image of A in y-axis be B and the image of B in x-axis be C. If D(3 cos θ, a sin θ) is a point in the fourth quadrant such that the maximum area of ∆ACD is 12 square units, then a is equal to _______.

Answer: (8)

24. Let a line having direction ratios 1, −4, 2 intersect the lines  and  at the point A and B. Then (AB)2 is equal to __________.

Answer: (84)

25. The number of points where the function

[t] denotes the greatest integer ≤ t, is discontinuous is _________.

Answer: (7)

26. Let  Then the value of is __________.

Answer: (1)

27. Let  If  then α1 + α2 is equal to __________

Answer: (34)

28. If two tangents drawn from a point (α, β) lying on the ellipse 25x2 + 4y2 = l to the parabola y2 = 4x are such that the slope of one tangent is four times the other, then the value of (10α + 5)2 + (16β2 + 50)2 equals __________

Answer: (2929)

29. Let S be the region bounded by the curves y = x3 and y2 = x. The curve y = 2|x| divides S into two regions of areas R1 and R2.

If max {R1, R2} = R2, then R2/R1 is equal to __________.

Answer: (19)

30.If the shortest distance between the line  and  then the integral value of a is equal to

Answer: (2)

JEE Main Online Computer Based Test (CBT) Examination Held on 16-04-2018 Morning Question Paper With Answer Key

JEE Main Online Computer Based Test (CBT) Examination Morning Held on 16-04-2018

Timing : 9 : 30 AM – 12 : 30 PM

PHYSICS 

1. The percentage errors in quantities P, Q, R and S are 0.5%, 1%, 3% and 1.5% respectively in the measurement of a physical quantity The maximum percentage error in the value of A will be :

(1)   6.0%

(2)   7.5%

(3)   8.5%

(4)   6.5%

Answer: (4)

2. Let  The magnitude of a coplanar vector  such that  is given by :

(1) 

(2) 

(3) 

(4) 

Answer: (2)

3. A body of mass m starts moving from rest along x-axis so that its velocity varies as  where a is a constant and s is the distance covered by the body. The total work done by all the forces acting on the body in the first t seconds after the start of the motion is :

(1) 

(2)   8 m a4t2

(3)   4 m a4t2

(4) 

Answer: (1)

4. Two particles of the same mass m are moving in circular orbits because of force, given by

The first particle is at a distance r=1, and the second, at r=4. The best estimate for the ratio of kinetic energies of the first and the second particle is closest to :

(1)   6 × 102

(2)   3 × 103

(3)   10−1

(4)   6 × 102

Answer: (1)

5. An oscillator of mass M is at rest in its equilibrium position in a potential  A particle of mass m comes from right with speed u and collides completely inelastically with M and sticks to it. This process repeats every time the oscillator crosses its equilibrium position. The amplitude of oscillations after 13 collisions is : (M = 10, m = 5, u = 1, k = 1)

(1) 

(2)   1/2

(3)   2/3

(4) 

Answer: (1)

6. Suppose that the angular velocity of rotation of earth is increased. Then, as a consequence :

(1)   Weight of the object, everywhere on the earth, will increase.

(2)   Weight of the object, everywhere on the earth, will decrease.

(3)   There will be no change in weight anywhere on the earth.

(4)   Except at poles, weight of the object on the earth will decrease.

Answer: (4)

7. A thin circular disk is in the xy plane as shown in the figure. The ratio of its moment of inertia about z and zʹ axes will be :

(1)   1 : 3

(2)   1 : 4

(3)   1 : 5

(4)   1 : 2

Answer: (1)

8. The relative uncertainty in the period of a satellite orbiting around the earth is 10−2. If the relative uncertainty in the radius of the orbit is negligible, the relative uncertainty in the mass of the earth is :

(1)   10−2

(2)   2 × 10−2

(3)   3 × 10−2

(4)   6 × 10−2

Answer: (2)

9. A small soap bubble of radius 4 cm is trapped inside another bubble of radius 6 cm without any contact. Let P2 be the pressure inside the inner bubble and P0, the pressure outside the outer bubble. Radius of another bubble with pressure difference P2 − P0 between its inside and outside would be :

(1)   12 cm

(2)   2.4 cm

(3)   6 cm

(4)   4.8 cm

Answer: (2)

10. One mole of an ideal monoatomic gas is taken along the path ABCA as shown in the PV diagram. The maximum temperature attained by the gas along the path BC is given by :

(1)  

(2) 

(3) 

(4)    

Answer: (2)

11. Two moles of helium are mixed with n moles of hydrogen. If  for the mixture, then the value of n is :

(1)   1

(2)   3

(3)   2

(4)   3/2

Answer: (3)

12. A particle executes simple harmonic motion and is located at x=a, b and c at times to, 2to and 3to The frequency of the oscillation is :

(1)    

(2) 

(3)    

(4)     

Answer: (1)

13. Two sitar strings, A and B, playing the note ‘Dha’ are slightly out of tune and produce beats of frequency 5 Hz. The tension of the string B is slightly increased and the beat frequency is found to decrease by 3 Hz. If the frequency of A is 425 Hz, the original frequency of B is :

(1)   430 Hz

(2)   420 Hz

(3)   428 Hz

(4)   422 Hz

Answer: (2)

14. Two identical conducting spheres A and B, carry equal charge. They are separated by a distance much larger than their diameters, and the force between them is F. A third identical conducting sphere, C, is uncharged. Sphere C is first touched to A, then to B, and then removed. As a result, the force between A and B would be equal to :

(1)   F

(2)   3F/4

(3)   3F/8

(4)   F/2

Answer: (3)

15. A heating element has a resistance of 100 Ω at room temperature. When it is connected to a supply of 220 V, a steady current of 2 A passes in it and temperature is 500°C more than room temperature. What is the temperature coefficient of resistance of the heating element ?

(1)   0.5 × 104 °C1

(2)   5 × 104 °C1

(3)   1 × 104 °C1

(4)   2 × 104 °C1

Answer: (4)

16. A galvanometer with its coil resistance 25 Ω requires a current of 1 mA for its full deflection. In order to construct an ammeter to read up to a current of 2 A, the approximate value of the shunt resistance should be :

(1)   2.5 × 103 Ω

(2)   1.25 × 102 Ω

(3)   1.25 × 103 Ω

(4)   2.5 × 102 Ω

Answer: (2)

17. In the following circuit, the switch S is closed at t=0. The charge on the capacitor C1 as a function of time will be given by 

(1)   C1E [1 − exp(−tR/C1)]

(2)   C2E [1 − exp(−t/RC2)]

(3)   CeqE [1 − exp(−t/RCeq)]

(4)   CeqE exp (−t/RCeq)

Answer: (3)

18. A coil of cross-sectional area A having n turns is placed in a uniform magnetic field B. When it is rotated with an angular velocity ω, the maximum e.m.f. induced in the coil will be :

(1)   3 nBAω

(2)  

(3)   nBAω

(4)    

Answer: (3)

19. A charge q is spread uniformly over an insulated loop of radius r. If it is rotated with an angular velocity ω with respect to normal axis then the magnetic moment of the loop is :

(1)   q ωr2

(2)    

(3)    

(4)    

Answer: (4)

20. A power transmission line feeds input power at 2300 V to a step down transformer with its primary windings having 4000 turns, giving the output power at 230 V. If the current in the primary of the transformer is 5 A, and its efficiency is 90%, the output current would be :

(1)   50 A

(2)   45 A

(3)   25 A

(4)   20 A

Answer: (2)

21. A plane electromagnetic wave of wavelength λ has an intensity I. It is propagating along the positive Y-direction. The allowed expressions for the electric and magnetic fields are given by :

(1)  

(2)  

(3)    

(4)  

Answer: (1)

22. A ray of light is incident at an angle of 60° on one face of a prism of angle 30°. The emergent ray of light makes an angle of 30° with incident ray. The angle made by the emergent ray with second face of prism will be :

(1)   0°

(2)   90°

(3)   45°

(4)   30°

Answer: (2)

23. Unpolarized light of intensity I is incident on a system of two polarizers, A followed by B. The intensity of emergent light is I/2. If a third polarizer C is placed between A and B, the intensity of emergent light is reduced to I/3. The angle between the polarizers A and C is θ. Then :

(1)    

(2)  

(3)    

(4)    

Answer: (2)

24. The de-Broglie wavelength (λB) associated with the electron orbiting in the second excited state of hydrogen atom is related to that in the ground state (λG) by :

(1)   λB = 2λG

(2)   λB = 3λG

(3)   λB = λG/2

(4)   λB = λG/3

Answer: (2)

25. Both the nucleus and the atom of some element are in their respective first excited states. They get de-excited by emitting photons of wavelengths λN, λA The ratio  is closest to :

(1)   106

(2)   10

(3)   1010

(4)   101

Answer: (1)

26. At some instant, a radioactive sample S1 having an activity 5 μCi has twice the number of nuclei as another sample S2 which has an activity of 10 μCi. The half lives of S1 and S2 are :

(1)   20 years and 5 years, respectively

(2)   20 years and 10 years, respectively

(3)   5 years and 20 years, respectively

(4)   10 years and 20 years, respectively

Answer: (1)

27. In the given circuit, the current through zener diode is :

(1)   5.5 mA

(2)   6.7 mA

(3)   2.5 mA

(4)   3.3 mA

Answer: (4)

28. A carrier wave of peak voltage 14 V is used for transmitting a message signal. The peak voltage of modulating signal given to achieve a modulation index of 80% will be :

(1)   7 V

(2)   28 V

(3)   11.2 V

(4)   22.4 V

Answer: (3)

29. In a circuit for finding the resistance of a galvanometer by half deflection method, a 6 V battery and a high resistance of 11 kΩ are used. The figure of merit of the galvanometer is 60 μA/division. In the absence of shunt resistance, the galvanometer produces a deflection of θ = 9 divisions when current flows in the circuit. The value of the shunt resistance that can cause the deflection of θ/2, is closest to :

(1)   550 Ω

(2)   220Ω

(3)   55Ω

(4)   110Ω

Answer: (4)

30. The end correction of a resonance column is 1 cm. If the shortest length resonating with the tuning fork is 10 cm, the next resonating length should be :

(1)   28 cm

(2)   32 cm

(3)   36 cm

(4)   40 cm

Answer: (2)

CHEMISTRY

31. An unknown chlorohydrocarbon has 3.55% of chlorine. If each molecule of the hydrocarbon has one chlorine atom only; chlorine atoms present in 1 g of chlorohydrocarbon are :

(Atomic wt. of Cl=35.5 u; Avogadro constant=6.023 × 1023 mol−1)

(1)   6.023 × 1020

(2)   6.023 × 109

(3)   6.023 × 1021

(4)   6.023 × 1023

Answer: (1)

32. The gas phase reaction 2NO2(g) → N2O4(g) is an exothermic reaction. The decomposition of N2O4, in equilibrium mixture of NO2(g) and N2O4(g), can be increased by :

(1)   lowering the temperature.

(2)   increasing the pressure.

(3)   addition of an inert gas at constant volume.

(4)   addition of an inert gas at constant pressure.

Answer: (4)

33. Assuming ideal gas behaviour, the ratio of density of ammonia to that of hydrogen chloride at same temperature and pressure is : (Atomic wt. of Cl=35.5 u)

(1)   1.46

(2)   0.46

(3)   1.64

(4)   0.64

Answer: (2)

34. When 9.65 ampere current was passed for 1.0 hour into nitrobenzene in acidic medium, the amount of p-aminophenol produced is :

(1)   9.81 g

(2)   10.9 g

(3)   98.1 g

(4)   109.0 g

Answer: (1)

35. For which of the following processes, ΔS is negative ?

(1)   H2(g) → 2H(g)

(2)   N2(g, 1 atm) → N2(g, 5 atm)

(3)   C(diamond) → C(graphite)

(4)   N2(g, 273 K) → N2(g, 300 K)

Answer: (2)

36. Which one of the following is not a property of physical adsorption ?

(1)   Higher the pressure, more the adsorption

(2)   Lower the temperature, more the adsorption

(3)   Greater the surface area, more the adsorption

(4)   Unilayer adsorption occurs

Answer: (4)

37. If 50% of a reaction occurs in 100 second and 75% of the reaction occurs in 200 second, the order of this reaction is :

(1)   Zero

(2)   1

(3)   2

(4)   3

Answer: (2)

38. Which of the following statements is false ?

(1)   Photon has momentum as well as wavelength.

(2)   Splitting of spectral lines in electrical field is called Stark effect.

(3)   Rydberg constant has unit of energy.

(4)   Frequency of emitted radiation from a black body goes from a lower wavelength to higher wavelength as the temperature increases.

Answer: (4)

39. At 320 K, a gas A2 is 20% dissociated to A(g). The standard free energy change at 320 K and 1 atm in J mol−1 is approximately : (R=8.314 JK−1 mol−1; ln 2=0.693; ln 3=1.098)

(1)   4763

(2)   2068

(3)   1844

(4)   4281

Answer: (1)

40. The mass of a non-volatile, non-electrolyte solute (molar mass=50 g mol−1) needed to be dissolved in 114 g octane to reduce its vapour pressure to 75%, is :

(1)   37.5 g

(2)   75 g

(3)   150 g

(4)   50 g

Answer: (3)

41. The incorrect statement is :

(1)   Cu2+ salts give red coloured borax bead test in reducing flame.

(2)   Cu2+ and Ni2+ ions give black precipitate with H2S in presence of HCl solution.

(3)   Ferricion gives blood red colour with potassium thiocyanate.

(4)   Cu2+ ion gives chocolage coloured precipitate with potassium ferrocyanide solution.

Answer: (2)

42. The incorrect geometry is represented by :

(1)   BF3 – trigonal planar

(2)   H2O – bent

(3)   NF3 – trigonal planar

(4)   AsF5 – trigonal bipyramidal

Answer: (3)

43. In Wilkinson’s catalyst, the hybridization of central metal ion and its shape are respectively :

(1)   sp3d, trigonal bipyramidal

(2)   sp3, tetrahedral

(3)   dsp2, square planar

(4)   d2sp3, octahedral

Answer: (3)

44. Among the oxides of nitrogen : N2O3, N2O4 and N2O5 ; the molecule(s) having nitrogen-nitrogen bond is/are :

(1)   Only N2O5

(2)   N­2O3 and N2O5

(3)   N2O4 and N2O5

(4)   N2O3­ and N2O4

Answer: (4)

45. Which of the following complexes will show geometrical isomerism ?

(1)   aquachlorobis(ethylenediamine) cobalt(II) chloride

(2)   pentaaquachlorochromium(III) chloride

(3)   potassium amminetrichloroplatinate (II)

(4)   potassium tris(oxalato)chromate(III)

Answer: (1)

46. In a complexometric titration of metal ion with ligand M(Metal ion)+L(Ligand) → C(Complex) end point is estimated spectrophotometrically (through light absorption). If ‘M’ and ‘C’ do not absorb light and only ‘L’ absorbs, then the titration plot between absorbed light (A) versus volume of ligand ‘L’ (V) would look like :

(1)  

(2) 

(3)  

(4)  

Answer: (2)

47. In the extraction of copper from its sulphide ore, metal is finally obtained by the oxidation of cuprous sulphide with :

(1)   Fe2O3

(2)   Cu2O

(3)   SO2

(4)   CO

Answer: (2)

48. Which of the following conversions involves change in both shape and hybridisation ?

(1)   NH3 → NH4+

(2)   CH4 → C2H6

(3)   H2O → H3O+

(4)   BF­3 → BF4

Answer: (4)

49. A group 13 element ‘X’ reacts with chlorine gas to produce a compound XCl3 . XCl3 is electron deficient and easily reacts with NH3 to form Cl3X ← NH3 adduct; however, XCl3 does not dimerize. X is :

(1)   B

(2)   Al

(3)   Ga

(4)   In

Answer: (1)

50. When XO2 is fused with an alkali metal hydroxide in presence of an oxidizing agent such as KNO3 ; a dark green product is formed which disproportionates in acidic solution to afford a dark purple solution. X is :

(1)   Ti

(2)   V

(3)   Cr

(4)   Mn

Answer: (4)

51. The major product of the following reaction is :

(1)  

(2)  

(3)  

(4)  

Answer: (1)

52. For standardizing NaOH solution, which of the following is used as a primary standard ?

(1)   Ferrous Ammonium Sulfate

(2)   dil. HCl

(3)   Oxalic acid

(4)   Sodium tetraborate

Answer: (3)

53. The most polar compound among the following is :

(1)  

(2)  

(3)  

(4)  

Answer: (1)

54. The correct match between items of List – I and List – II is :

(1)   (A)-(R), (B)-(S), (C)-(P), (D)-(Q)

(2)   (A)-(S), (B)-(R), (C)-(P), (D)-(Q)

(3)   (A)-(S), (B)-(R), (C)-(Q), (D)-(P)

(4)   (A)-(R), (B)-(S), (C)-(Q), (D)-(P)

Answer: (1)

55. Among the following, the incorrect statement is :

(1)   Maltose and lactose has 1, 4-glycosidic linkage.

(2)   Sucrose and amylose has 1, 2-glycosidic linkage.

(3)   Cellulose and amylose has 1, 4-glycosidic linkage.

(4)   Lactose contains β-D-galactose and β-D-glucose.

Answer: (2)

56. Which of the following compounds will most readily be dehydrated to give alkene under acidic condition ?

(1)   1-Pentanol

(2)   4-Hydroxypentan-2-one

(3)   3-Hydroxypentan-2-one

(4)   2-Hydroxycyclopentanone

Answer: (2)

57. Products A and B formed in the following reactions are respectively :

(1)  

(2)   

(3)  

(4)  

Answer: (4)

58. The major product B formed in the following reaction sequence is :

(1)  

(2)  

(3)  

(4)  

Answer: (2)

59. The major product of the following reaction is :

(1)   

(2) 

(3)   

(4) 

Answer: (1)

60. The major product of the following reaction is :

(1)   

(2)   

(3)   

(4)  

Answer: (1)

MATHEMATICS

61. Let N denote the set of all natural numbers. Define two binary relations on N as R1={(x, y) ϵ N × N : 2x + y = 10} and R2={(x, y) ϵ N × N : x + 2y = 10}. Then :

(1)   Range of R1 is {2, 4, 8}.

(2)   Range of R2 is {1, 2, 3, 4}.

(3)   Both R1 and R2 are symmetric relations.

(4)   Both R1 and R2 are transitive relations.

Answer: (2)

62. Let p, q and r be real numbers (p ≠ q, r ≠ 0), such that the roots of the equation  are equal in magnitude but opposite in sign, then the sum of squares of these roots is equal to :

(1)     

(2)   p2 + q2

(3)   2(p2 + q2)

(4)   p2 + q2 + r2

Answer: (2)

63. The least positive integer n for which  is

(1)   2

(2)   3

(3)   5

(4)   6

Answer: (2)

64. Let  and B = A20. Then the sum of the elements of the first column of B is :

(1)   210

(2)   211

(3)   231

(4)   251

Answer: (3)

65. The number of values of k for which the system of linear equations,

(k + 2)x + 10y = k

kx + (k + 3)y = k – 1

has no solution, is :

(1)   1

(2)   2

(3)   3

(4)   infinitely many

Answer: (1)

66. The number of numbers between 2,000 and 5,000 that can be formed with the digits 0, 1, 2, 3, 4 (repetition of digits is not allowed) and are multiple of 3 is :

(1)   24

(2)   30

(3)   36

(4)   48

Answer: (2)

67. The coefficient of x2 in the expansion of the product (2− x2) ⋅ ((1 + 2x + 3x2)6+ (1 − 4x2)6) is :

(1)   107

(2)   106

(3)   108

(4)   155

Answer: (2)

68. Let  (xi ≠ 2 for i = 1, 2, . . . , n) be in A.P. such that x1 = 4 and x21 = 20. If n is the least positive integer for which xn > 50, then  is equal to :

(1)   1/8

(2)   3

(3)   13/8

(4)   13/4

Answer: (4)

69. The sum of the first 20 terms of the series  is :

(1)    

(2)    

(3)    

(4)    

Answer: (1)

70. 

(1)   1/3

(2)   −1/3

(3)   −1/6

(4)   1/6

Answer: (3)

71. If the function f defined as  is continuous at x = 0, then the ordered pair (k, f(0)) is equal to :

(1)   (3, 2)

(2)   (3, 1)

(3)   (2, 1)

(4)   (1/3, 2)

Answer: (2)

72. If  then  is equal to :

(1)   y/x

(2)   x/y

(3)   −y/x

(4)   −x/y

Answer: (3)

73. Let M and m be respectively the absolute maximum and the absolute minimum values of the function, f (x)=2x3 − 9x2 + 12x + 5 in the interval [0, 3]. Then M−m is equal to :

(1)   5

(2)   9

(3)   4

(4)   1

Answer: (2)

74. If  (C is a constant of integration), then the ordered pair (K, A) is equal to :

(1)   (2, 1)

(2)   (−2, 3)

(3)   (2, 3)

(4)   (−2, 1)

Answer: (3)

75. If  then :

(1)   fʹʹʹ(x) + fʹʹ(x) = sin x

(2)   fʹʹʹ(x) + fʹʹ(x) – fʹ(x) = cos x

(3)   fʹʹʹ(x) + fʹ(x) = cos x – 2x sin x

(4)   fʹʹʹ(x) – fʹʹ(x) = cos x – 2x sin x

Answer: (3)

76. If the area of the region bounded by the curves, y = x2, y = 1/x and the lines y = 0 and x = t (t > 1) is 1 sq. unit, then it is equal to :

(1)   e3/2

(2)   4/3

(3)   3/2

(4)   e2/3

Answer: (4)

77. The differential equation representing the family of ellipses having foci either on the x-axis or on the y-axis, centre at the origin and passing through the point (0, 3) is :

(1)   xy yʹʹ + x(yʹ)2 – y yʹ = 0

(2)   x + y yʹʹ = 0

(3)   xy yʹ + y2 – 9 = 0

(4)   xy yʹ – y2 + 9 = 0

Answer: (4)

78. The locus of the point of intersection of the lines,  and   (k is any non-zero real parameter), is :

(1)   an ellipse whose eccentricity is 1/√3.

(2)   an ellipse with length of its major axis 8√2.

(3)   a hyperbola whose eccentricity is √3.

(4)   a hyperbola with length of its transverse axis 8√2.

Answer: (4)

79. If a circle C, whose radius is 3, touches externally the circle, x2 + y2 + 2x − 4y – 4 = 0 at the point (2, 2), then the length of the intercept cut by this circle C, on the x-axis is equal to :

(1)   2√5

(2)   3√2

(3)   √5

(4)   2√3

Answer: (1)

80. Let P be a point on the parabola, x2 = 4y. If the distance of P from the centre of the circle, x2 + y2 + 6x + 8 = 0 is minimum, then the equation of the tangent to the parabola at P, is :

(1)   x + 4y – 2 = 0

(2)   x – y + 3 = 0

(3)   x + y + 1 = 0

(4)   x + 2y = 0

Answer: (3)

81. If the length of the latus rectum of an ellipse is 4 units and the distance between a focus and its nearest vertex on the major axis is 3/2 units, then its eccentricity is :

(1)   1/2

(2)   1/3

(3)   2/3

(4)   1/9

Answer: (2)

82. The sum of the intercepts on the coordinate axes of the plane passing through the point (−2, −2, 2) and containing the line joining the points (1, −1, 2) and (1, 1, 1), is :

(1)   4

(2)   −4

(3)   −8

(4)   12

Answer: (2)

83. If the angle between the lines,  is  then p is  equal to :

(1)   7/2

(2)   2/7

(3)   −7/4

(4)   −4/7

Answer: (1)

84. Let  and a vector  be such that  Then  equals :

(1)   11/3

(2)   11/√3

(3)    

(4)    

Answer: (3)

85. The mean and the standard deviation(s.d.) of five observations are 9 and 0, respectively. If one of the observations is changed such that the mean of the new set of five observations becomes 10, then their s.d. is :

(1)   0

(2)   1

(3)   2

(4)   4

Answer: (3)

86. Let A, B and C be three events, which are pair-wise independent and  denotes the complement of an event E. If P(A ∩ B ∩ C) = 0 and P(C) > 0, then  is equal to :

(1)     

(2)    

(3)    

(4)    

Answer: (1)

87. Two different families A and B are blessed with equal number of children. There are 3 tickets to be distributed amongst the children of these families so that no child gets more than one ticket. If the probability that all the tickets go to the children of the family B is 1/12, then the number of children in each family is :

(1)   3

(2)   4

(3)   5

(4)   6

Answer: (3)

88. If an angle A of a ΔABC satisfies 5 cosA+3=0, then the roots of the quadratic equation, 9x2 + 27x + 20=0 are :

(1)   sec A, cot A

(2)   sin A, sec A

(3)   sec A, tan A

(4)   tan A, cos A

Answer: (3)

89. A man on the top of a vertical tower observes a car moving at a uniform speed towards the tower on a horizontal road. If it takes 18 min. for the angle of depression of the car to change from 30° to 45° ; then after this, the time taken (in min.) by the car to reach the foot of the tower, is :

(1)    

(2)    

(3)    

(4)    

Answer: (1)

90. If p→(∼p∨∼q) is false, then the truth values of p and q are respectively :

(1)   F, F

(2)   T, F

(3)   F, T

(4)   T, T

Answer: (4)

JEE Main Online Computer Based Test (CBT) Examination Held on 15-04-2018 Afternoon Question Paper With Answer Key

JEE Main Online Computer Based Test (CBT) Examination Afternoon Held on 15-04-2018,

Timing : 2:30 PM – 5.30 PM

PHYSICS 

1. The characteristic distance at which quantum gravitational effects are significant, the Planck length, can be determined from a suitable combination of the fundamental physical constants G, h and c. Which of the following correctly gives the Planck length ?

(1)   G h2 c3

(2)   G2 h c

(3)   G1/2 h2 c

(4) 

Answer: (4)

2. A man in a car at location Q on a straight highway is moving with speed υ. He decides to reach a point P in a field at a distance d from the highway (point M) as shown in the figure. Speed of the car in the field is half to that on the highway. What should be the distance RM, so that the time taken to reach P is minimum ?

(1)   d

(2)   d/√2

(3)   d/2

(4)   d/√3

Answer: (4)

3. A body of mass 2 kg slides down with an acceleration of 3 m/s2 on a rough inclined plane having a slope of 30°. The external force required to take the same body up the plane with the same acceleration will be : (g=10 m/s2)

(1)   14 N

(2)   20 N

(3)   6 N

(4)   4 N

Answer: (2)

4. A proton of mass m collides elastically with a particle of unknown mass at rest. After the collision, the proton and the unknown particle are seen moving at an angle of 90° with respect to each other. The mass of unknown particle is :

(1)   m/2

(2)   m

(3)   m/√3

(4)   2 m

Answer: (2)

5. A disc rotates about its axis of symmetry in a horizontal plane at a steady rate of 3.5 revolutions per second. A coin placed at a distance of 1.25 cm from the axis of rotation remains at rest on the disc. The coefficient of friction between the coin and the disc is : (g=10 m/s2)

(1)   0.5

(2)   0.3

(3)   0.7

(4)   0.6

Answer: (4)

6. A thin uniform bar of length L and mass 8 m lies on a smooth horizontal table. Two point masses m and 2 m are moving in the same horizontal plane from opposite sides of the bar with speeds 2υ and υ respectively. The masses stick to the bar after collision at a distance  respectively from the centre of the abr. If the bar starts rotating about its center of mass as a result of collision, the angular speed of the bar will be :

(1) 

(2) 

(3) 

(4) 

Answer: (2)

7. A thin rod MN, free to rotate in the vertical plane about the fixed end N, is held horizontal. When the end M is released the speed of this end, when the rod makes an angle α with the horizontal, will be proportional to : (see figure)

(1) 

(2)   sin α

(3) 

(4)   cos α

Answer: (1)

8. As shown in the figure, forces of 105 N each are applied in opposite directions, on the upper and lower faces of a cube of side 10 cm, shifting the upper face parallel to itself by 0.5 cm. If the side of another cube of the same material is 20 cm, then under similar conditions as above, the displacement will be :

(1)   0.25 cm

(2)   0.37 cm

(3)   0.75 cm

(4)   1.00 cm

Answer: (1)

9. When an air bubble of radius r rises from the bottom to the surface of a lake, its radius becomes 5r/4. Taking the atmospheric pressure to be equal to 10 m height of water column, the depth of the lake would approximately be (ignore the surface tension and the effect of temperature) :

(1)   11.2 m

(2)   8.7 m

(3)   9.5 m

(4)   10.5 m

Answer: (3)

10. Two Carnot engines A and B are operated in series. Engine A receives heat from a reservoir at 600 K and rejects heat to a reservoir at temperature T. Engine B receives heat rejected by engine A and in turn rejects it to a reservoir at 100 K. If the efficiencies of the two engines A and B are represented by ηA and ηB, respectively, then what is the value of 

(1)   12/7

(2)   7/12

(3)   12/5

(4)   5/12

Answer: (1)

11. The value closest to the thermal velocity of a Helium atom at room temperature (300 K) in ms1 : [kB = 1.4 × 1023 J/K; mHe = 7 × 1027 kg]

(1)   1.3 × 104

(2)   1.3 × 103

(3)   1.3× 105

(4)   1.3 × 102

Answer: (2)

12. Two simple harmonic motions, as shown below, are at right angles. They are combined to form Lissajous figures.

         x(t) = A sin (at + δ)

         y(t) = B sin (bt)

Identify the correct match below.

          Parameters                      Curve

(1)   A ≠ B, a = b ; δ = 0            Parabola

(2)   A = B, a = b ; δ = π/2         Line

(3)   A ≠ B, a = b ; δ = π/2         Ellipse

(4)   A = B, a = 2b ; δ = π/2       Circle

Answer: (3)

13. 5 beats/second are heard when a tuning fork is sounded with a sonometer wire under tension, when the length of the sonometer wire is either 0.95 m or 1 m. The frequency of the fork will be :

(1)   195 Hz

(2)   150 Hz

(3)   300 Hz

(4)   251 Hz

Answer: (1)

14. A solid ball of radius R has a charge density ρ given by ρ = ρ0(1 – r/R) for 0 ≤ r ≤ The electric field outside the ball is :

(1) 

(2) 

(3) 

(4) 

Answer: (2)

15. A parallel plate capacitor with area 200 cm2 and separation between the plates 1.5 cm, is connected across a battery of emf V. If the force of attraction between the plates is 25×10−6 N, the value of V is approximately :

(1)   250 V

(2)   100 V

(3)   300 V

(4)   150 V

Answer: (1)

16. A copper rod of cross-sectional area A carries a uniform current I through it. At temperature T, if the volume charge density of the rod is ρ, how long will the charges take to travel a distance d ?

(1) 

(2) 

(3) 

(4) 

Answer: (3)

17. A capacitor C1=1.0 μF is charged up to a voltage V=60 V by connecting it to battery B through switch (1). Now C1 is disconnected from battery and connected to a circuit consisting of two uncharged capacitors C2=3.0 μF and C3=6.0 μF through switch (2), as shown in the figure. The sum of final charges on C2 and C3 is :

(1)   40 μC

(2)   36 μC

(3)   20 μC

(4)   54 μC

Answer: (1)

18. A current of 1 A is flowing on the sides of an equilateral triangle of side 4.5×10−2 The magnetic field at the centre of the triangle will be :

(1)   2 ×10−5 Wb/m2

(2)   Zero

(3)   8 ×10−5 Wb/m2

(4)   4 ×10−5 Wb/m2

Answer: (4)

19. At the centre of a fixed large circular coil of radius R, a much smaller circular coil of radius r is placed. The two coils are concentric and are in the same The larger coil carries a current I. The smaller coil is set to rotate with a constant angular velocity ω about an axis along their common diameter. Calculate the emf induced in the smaller coil after a time t of its start of rotation.

(1) 

(2) 

(3) 

(4) 

Answer: (1)

20. 

A copper rod of mass m slides under gravity on two smooth parallel rails, with

separation l and set at an angle of θ with the horizontal. At the bottom, rails are joined by a resistance R. There is a uniform magnetic field B normal to the plane of the rails, as shown in the figure. The terminal speed of the copper rod is :

(1) 

(2) 

(3) 

(4) 

Answer: (3)

21. A plane polarized monochromatic EM wave is traveling in vacuum along z direction such that at t = t1 it is found that the electric field is zero at a spatial point z1. The next zero that occurs in its neighbourhood is at z2. The frequency of the electromagnetic wave is :

(1) 

(2) 

(3) 

(4) 

Answer: (2)

22. A convergent doublet of separated lenses, corrected for spherical aberration, has resultant focal length of 10 cm. The separation between the two lenses is 2 cm. The focal lengths of the component lenses are :

(1)   10 cm, 12 cm

(2)   12 cm, 14 cm

(3)   16 cm, 18 cm

(4)   18 cm, 20 cm

Answer: (4)

23. A plane polarized light is incident on a polariser with its pass axis making angle θ with x-axis, as shown in the figure. At four different values of θ, θ=8°, 38°, 188° and 218°, the observed intensities are same. What is the angle between the direction of polarization and x-axis ?

(1)   98°

(2)   128°

(3)   203°

(4)   45°

Answer: (3)

24. If the de Broglie wavelengths associated with a proton and an α-particle are equal, then the ratio of velocities of the proton and the α-particle will be :

(1)   4 : 1

(2)   2 : 1

(3)   1 : 2

(4)   1 : 4

Answer: (1)

25. Muon (μ) is a negatively charged (|q| = |e|) particle with a mass mμ=200 me, where me is the mass of the electron and e is the electronic charge. If μ is bound to a proton to form a hydrogen like atom, identify the correct statements.

(A)  Radius of the muonic orbit is 200 times smaller than that of the electron.

(B)  The speed of the μ in the nth orbit is 1/200 times that of the electron in the nth orbit.

(C)  The ionization energy of muonic atom is 200 times more than that of an hydrogen atom.

(D)  The momentum of the muon in the nth orbit is 200 times more than that of the electron.

(1)   (A), (B), (D)

(2)   (A), (C), (D)

(3)   (B), (D)

(4)   (C), (D)

Answer: (2)

26. An unstable heavy nucleus at rest breaks into two nuclei which move away with velocities in the ratio of 8 : 27. The ratio of the radii of the nuclei (assumed to be spherical) is :

(1)   8 : 27

(2)   4 : 9

(3)   3 : 2

(4)   2 : 3

Answer: (3)

27. Truth table for the following digital circuit will be :

(1) 

(2) 

(3) 

(4) 

Answer: (3)

28. The carrier frequency of a transmitter is provided by a tank circuit of a coil of inductance 49 μH and a capacitance of 2.5 nF. It is modulated by an audio signal of 12 kHz. The frequency range occupied by the side bands is :

(1)   13482 kHz − 13494 kHz

(2)   442 kHz − 466 kHz

(3)   63 kHz − 75 kHz

(4)   18 kHz − 30 kHz

Answer: (2)

29. A constant voltage is applied between two ends of a metallic wire. If the length is halved and the radius of the wire is doubled, the rate of heat developed in the wire will be :

(1)   Doubled

(2)   Halved

(3)   Unchanged

(4)   Increased 8 times

Answer: (4)

30. A body takes 10 minutes to cool from 60°C to 50° The temperature of surroundings is constant at 25°C. Then, the temperature of the body after next 10 minutes will be approximately :

(1)   47°C

(2)   41°C

(3)   45°C

(4)   43°C

Answer: (4)

CHEMISTRY

31. For per gram of reactant, the maximum quantity of N2 gas is produced in which of the following thermal decomposition reactions ?

(Given : Atomic wt. – Cr = 52 u, Ba = 137 u)

(1)   (NH4)2Cr2O7(s) → N2(g)+4H2O(g) +Cr2O3(s)

(2)   2NH4NO3(s) → 2 N2(g)+4H2O(g) +O2(g)

(3)   Ba(N3)2(s) → Ba(s)+3N2(g)

(4)   2NH3(g) → N2(g)+3H2(g)

Answer: (4)

32. All of the following share the same crystal structure except :

(1)   LiCl

(2)   NaCl

(3)   RbCl

(4)   CsCl

Answer: (4)

33. The de-Broglie’s wavelength of electron present in first Bohr orbit of ‘H’ atom is :

(1)   0529 Å

(2)   2π × 0.529 Å

(3) 

(4)   4 × 0.529 Å

Answer: (2)

34. ∆fG° at 500 K for substance ‘S’ in liquid state and gaseous state are +100.7 kcal mol−1 and +103 kcal mol−1, respectively. Vapour pressure of liquid ‘S’ at 500 K is approximately equal to :

(R – 2 cal K1 mol1)

(1)   0.1 atm

(2)   1 atm

(3)   10 atm

(4)   100 atm

Answer: (1)

35. Given

(i) 2Fe2O3(s) → 4Fe(s)+3O2(g) ∆rG° = +1487.0 kJ mol1

(ii) 2CO(g) + O2(g) → 2CO2(g); ∆rG° = −514.4 kJ mol1

Free energy change, ∆rG° for the reaction 2Fe2O3(s) + 6CO(g) → 4Fe(s) + 6CO2(g) will  be :

(1)   −112.4 kJ mol−1

(2)   −56.2 kJ mol−1

(3)   −168.2 kJ mol−1

(4)   −208.0 kJ mol−1

Answer: (2)

36. Two 5 molal solutions are prepared by dissolving a non-electrolyte non-volatile solute separately in the solvents X and Y. The molecular weights of the solvents are MX and MY, respectively where  The relative lowering of vapour pressure of the solution in X is “m” times that of the solution in Y. Given that the number of moles of solute is very small in comparison to that of solvent, the value of “m” is :

(1)   4/3

(2)   3/4

(3)   1/2

(4)   1/4

Answer: (2)

37. Following four solutions are prepared by mixing different volumes of NaOH and HCl of different concentrations, pH of which one of them will be equal to 1 ?

(1) 

(2) 

(3) 

(4) 

Answer: (2)

38. At a certain temperature in a 5 L vessel, 2 moles of carbon monoxide and 3 moles of chlorine were allowed to reach equilibrium according to the reaction,

CO + Cl2 ⇌ COCl2

At equilibrium, if one mole of CO is present then equilibrium constant (Kc) for the reaction is :

(1)   2

(2)   2.5

(3)   3

(4)   4

Answer: (2)

39. If x gram of gas is adsorbed by m gram of adsorbent at pressure P, the plot of  versus log P is linear. The slope of the plot is :

(n and k are constants and n > 1)

(1)   2 k

(2)   log k

(3)   n

(4)   1/n

Answer: (4)

40. For a first order reaction, A → P, t­1/2 (half-life) is 10 days. The time required for 1/4th conversion of A (in days) is :

(ln 2 = 0.693, ln 3 = 1.1)

(1)   5

(2)   3.2

(3)   4.1

(4)   2.5

Answer: (3)

41. Which of the following best describes the diagram below of a molecular orbital ?

(1)   A non-bonding orbital

(2)   An antibonding σ orbital

(3)   A bonding π orbital

(4)   An antibonding π orbital

Answer: (4)

42. Biochemical Oxygen Demand (BOD) value can be a measure of water pollution caused by the organic matter. Which of the following statements is correct ?

(1)   Aerobic bacteria decrease the BOD value.

(2)   Anaerobic bacteria increase the BOD value.

(3)   Clean water has BOD value higher than 10 ppm.

(4)   Polluted water has BOD value higher than 10 ppm.

Answer: (4)

43. In KO2, the nature of oxygen species and the oxidation state of oxygen atom are, respectively :

(1)   Oxide and −2

(2)   Superoxide and −1/2

(3)   Peroxide and −1/2

(4)   Superoxide and −1

Answer: (2)

44. The number of P−O bonds in P4O6 is :

(1)   6

(2)   9

(3)   12

(4)   18

Answer: (3)

45. Lithium aluminium hydride reacts with silicon tetrachloride to form :

(1)   LiCl, AlH3 and SiH4

(2)   LiCl, AlCl3 and SiH4

(3)   LiH, AlCl3 and SiCl2

(4)   LiH, AlH3 and SiH4

Answer: (2)

46. The correct order of spin-only magnetic moments among the following is :

(Atomic number : Mn=25, Co=27, Ni=28, Zn=30)

(1)   [ZnCl4]2− > [NiCl4]2− > [CoCl4]2− > [MnCl4]2−

(2)   [CoCl4]2− > [MnCl4]2− > [NiCl4]2− > [ZnCl4]2−

(3)   [NiCl4]2− > [CoCl4]2− > [MnCl4]2− > [ZnCl4]2−

(4)   [MnCl4]2− > [CoCl4]2− > [NiCl4]2− > [ZnCl4]2−

Answer: (4)

47. The correct order of electron affinity is :

(1)   F > Cl > O

(2)   F > O > Cl

(3)   Cl > F > O

(4)   O > F > Cl

Answer: (3)

48. In XeO3F2, the number of bond pair(s), π-bond(s) and lone pair(s) on Xe atom respectively are :

(1)   5, 2, 0

(2)   4, 2, 2

(3)   5, 3, 0

(4)   4, 4, 0

Answer: (3)

49. In the leaching method, bauxite ore is digested with a concentrated solution of NaOH that produces ‘X’. When CO2 gas is passed through the aqueous solution of ‘X’, a hydrated compound ‘Y’ is precipitated. ‘X’ and ‘Y’ respectively are :

(1)   NaAlO2 and Al2(CO3)3⋅ x H2O

(2)   Al(OH)3 and Al2O3⋅ x H2O

(3)   Na[Al(OH)4] and Al2O3⋅ x H2O

(4)   Na[Al(OH)4] and Al2(CO3)3⋅ x H2O

Answer: (3)

50. The total number of possible isomers for square-planar [Pt(Cl)(NO2)(NO3)(SCN)]2− is :

(1)   8

(2)   12

(3)   16

(4)   24

Answer: (2)

51. Two compounds I and II are eluted by column chromatography (adsorption of I > II). Which one of following is a correct statement ?

(1)   I moves faster and has higher Rf value than II

(2)   II moves faster and has higher Rf value than I

(3)   I moves slower and has higher Rf value than II

(4)   II moves slower and has higher Rf value than I

Answer: (2)

52. Which of the following statements is not true ?

(1)   Step growth polymerisation requires a bifunctional monomer.

(2)   Nylon 6 is an example of step growth polymerisation.

(3)   Chain growth polymerization includes both homopolymerisation and copolymerisation.

(4)   Chain growth polymerization involves homopolymerisation only.

Answer: (4)

53. When 2-butyne is treated with H2/ Lindlar’s catalyst, compound X is produced as the major product and when treated with Na/liq. NH3 it produces Y as the major product. Which of the following statements is correct ?

(1)   X will have higher dipole moment and higher boiling point than Y.

(2)   Y will have higher dipole moment and higher boiling point than X.

(3)   X will have lower dipole moment and lower boiling point than Y.

(4)   Y will have higher dipole moment and lower boiling point than X.

Answer: (1)

54. The increasing order of the acidity of the following carboxylic acids is :

(1)   I < III < II < IV

(2)   IV < II < III < I

(3)   II < IV < III < I

(4)   III < II < IV < I

Answer: (4)

55. The major product formed in the following reaction is :

(1) 

(2) 

(3) 

(4) 

Answer: (4)

56. On treatment of the following compound with a strong acid, the most susceptible site for bond cleavage is :

(1)   C1 – O2

(2)   O2 – C3

(3)   C4 – O5

(4)   O5 – C6

Answer: (2)

57. The increasing order of diazotisation of the following compounds is :

(1)   (a) < (b) < (c) < (d)

(2)   (a) < (d) < (b) < (c)

(3)   (a) < (d) < (c) < (b)

(4)   (d) < (c) < (b) < (a)

Answer: (3)

58. The dipeptide, Gln-Gly, on treatment with CH3COCl followed by aqueous work up gives :

(1) 

(2) 

(3) 

(4) 

Answer: (3)

59. The total number of optically active compounds formed in the following reaction is :

(1)   Two

(2)   Four

(3)   Six

(4)   Zero

Answer: (2)

60. The major product formed in the following reaction is :

(1) 

(2) 

(3) 

(4) 

Answer: (3)

MATHEMATICS

61. Let f : A → B be a function defined as  where A = R – {2} and B R – {1}. Then f is :

(1)   invertible and 

(2)   invertible and 

(3)   invertible and 

(4)   not invertible

Answer: (2)

62. If f (x) is a quadratic expression such that f (1)+f (2)=0, and −1 is a root of f (x)=0, then the other root of f (x)=0 is :

(1)   −5/8

(2)   −8/5

(3)   5/8

(4)   8/5

Answer: (4)

63. If |z – 3 + 2i| ≤ 4 then the difference between the greatest value and the least value of |z| is :

(1)   2√13

(2)   8

(3)   4 + √13

(4)   √13

Answer: (3)

64. Suppose A is any 3×3 non-singular matrix and (A − 3I) (A − 5I) = O, where I = I3 and O = O3. If αA + βA−1 = 4I, then α + β is equal to :

(1)   8

(2)   7

(3)   13

(4)   12

Answer: (1)

65. If the system of linear equations

x + ay + z = 3

x + 2y + 2z = 6

x + 5y + 3z = b

has no solution, then :

(1)   a=−1, b=9

(2)   a=−1, b ≠ 9

(3)   a ≠−1, b=9

(4)   a=1, b ≠ 9

Answer: (2)

66. The number of four letter words that can be formed using the letters of the word BARRACK is :

(1)   120

(2)   144

(3)   264

(4)   270

Answer: (4)

67. The coefficient of x10 in the expansion of (1+x)2(1+x2)3(1+x3)4 is equal to :

(1)   52

(2)   56

(3)   50

(4)   44

Answer: (1)

68. If a, b, c are in A.P. and a2, b2, c2 are in G.P. such that a < b < c and  then the value of a is :

(1) 

(2) 

(3) 

(4) 

Answer: (3)

69. Let  and Bn = 1 – An. Then, the least odd natural number p, so that Bn > An, for all n ≥ p, is :

(1)   9

(2)   7

(3)   11

(4)   5

Answer: (2)

70. 

(1)   1/4

(2)   1

(3)   1/2

(4)   −1/2

Answer: (3)

71. Let 

The value of k for which f is continuous at x = 2 is :

(1)   1

(2)   e

(3)   e1

(4)   e2

Answer: (3)

72. If  equals :

(1)   −√3 loge √3

(2)   √3 loge √3

(3)   −√3 loge 3

(4)   √3 loge 3

Answer: (2)

73. Let f (x) be a polynomial of degree 4 having extreme values at x = 1 and x = 2.

If  then f(−1) is equal to :

(1)   9/2

(2)   5/2

(3)   3/2

(4)   1/2

Answer: (1)

74. If 

(where C is a constant of integration), then the ordered pair (A, B) is equal to :

(1)   (2, 1)

(2)   (−2, −1)

(3)   (−2, 1)

(4)   (2, −1)

Answer: (2)

75. The value of integral  is :

(1) 

(2) 

(3) 

(4) 

Answer: (2)

76. If 

(1)   I2 > I3 > I1

(2)   I2 > I1 > I3

(3)   I3 > I2 > I1

(4)   I3 > I1 > I2

Answer: (3)

77. The curve satisfying the differential equation, (x2 − y2)dx+2xydy=0 and passing through the point (1, 1) is :

(1)   a circle of radius one.

(2)   a hyperbola.

(3)   an ellipse.

(4)   a circle of radius two.

Answer: (1)

78. The sides of a rhombus ABCD are parallel to the lines, x−y+2=0 and 7x−y+3=0. If the diagonals of the rhombus intersect at P(1, 2) and the vertex A (different from the origin) is on the y-axis, then the ordinate of A is :

(1)   5/2

(2)   7/4

(3)   2

(4)   7/2

Answer: (1)

79. The foot of the perpendicular drawn from the origin, on the line, 3x+y=λ(λ ≠ 0) is P. If the line meets x-axis at A and y-axis at B, then the ratio BP : PA is :

(1)   1 : 3

(2)   3 : 1

(3)   1 : 9

(4)   9 : 1

Answer: (4)

80. The tangent to the circle C1 : x2+y2 − 2x−1=0 at the point (2, 1) cuts off a chord of length 4 from a circle C2 whose centre is (3, −2). The radius of C2 is :

(1)   2

(2)   √2

(3)   3

(4)   √6

Answer: (4)

81. Tangents drawn from the point (−8, 0) to the parabola y2 = 8x touch the parabola at P and Q. If F is the focus of the parabola, then the area of the triangle PFQ (in sq. units) is equal to :

(1)   4x2 + 9y2 = 121

(2)   9x2 + 4y2 = 169

(3)   4x2 – 9y2 = 121

(4)   9x2 – 4y2 = 169

Answer: (3)

82. A normal to the hyperbola, 4x2 − 9y2 = 36 meets the co-ordinate axes x and y at A and B, respectively. If the parallelogram OABP (O being the origin) is formed, then the locus of P is :

(1)   4x2 + 9y2 = 121

(2)   9x2 + 4y2 = 169

(3)   4x2 – 9y2 = 121

(4)   9x2 – 4y2 = 169

Answer: (4)

83. An angle between the lines whose direction cosines are given by the equations, l + 3m + 5n = 0 and 5lm −2mn + 6nl = 0, is :

(1)   cos1 (1/3)

(2)   cos1 (1/4)

(3)   cos1 (1/6)

(4)   cos1 (1/8)

Answer: (3)

84. A plane bisects the line segment joining the points (1, 2, 3) and (−3, 4, 5) at right angles. Then this plane also passes through the point :

(1)   (−3, 2, 1)

(2)   (3, 2, 1)

(3)   (−1, 2, 3)

(4)   (1, 2, −3)

Answer: (1)

85. If the position vectors of the vertices A, B and C of a ∆ABC are respectively  and  then the position vector of the point, where the bisector of ∠A meets BC is :

(1) 

(2) 

(3) 

(4) 

Answer: (3)

86. A player X has a biased coin whose probability of showing heads is p and a player Y has a fair coin. They start playing a game with their own coins and play alternately. The player who throws a head first is a winner. If X starts the game, and the probability of winning the game by both the players is equal, then the value of ‘p’ is :

(1)   1/5

(2)   1/3

(3)   2/5

(4)   1/4

Answer: (2)

87. If the mean of the data : 7, 8, 9, 7, 8, 7, λ, 8 is 8, then the variance of this data is :

(1)   7/8

(2)   1

(3)   9/8

(4)   2

Answer: (2)

88. The number of solutions of sin 3x=cos 2x, in the interval (π/2, π) is :

(1)   1

(2)   2

(3)   3

(4)   4

Answer: (1)

89. A tower T1 of height 60 m is located exactly opposite to a tower T2 of height 80 m on a straight road. From the top of T1, if the angle of depression of the foot of T2 is twice the angle of elevation of the top of T2, then the width (in m) of the road between the feet of the towers T1 and T2 is :

(1)   10√2

(2)   10√3

(3)   20√3

(4)   20√2

Answer: (3)

90. Consider the following two statements :

Statement p :

The value of sin 120° can be derived by taking θ = 240° in the equation 

Statement q :

The angles A, B, C and D of any quadrilateral ABCD satisfy the equation 

Then the truth values of p and q are respectively :

(1)   F, T

(2)   T, F

(3)   T, T

(4)   F, F

Answer: (1)

JEE Main Online Computer Based Test (CBT) Examination Held on 15-04-2018 Morning Question Paper With Answer Key

JEE Main Online Computer Based Test (CBT) Examination Held on 15-04-2018

9:30 AM – 12.30 PM (Morning)

PHYSICS

1. In a common emitter configuration with suitable bias, it is given that RL is the load resistance and RBE is small signal dynamic resistance (input side). Then, voltage gain, current gain and power gain are given, respectively, by :

β is current gain, I­B, I­C and IE are respectively base, collector and emitter currents.

(1) 

(2) 

(3) 

(4) 

Answer: (1)

2. A thin uniform tube is bent into a circle of radius r in the vertical plane. Equal volumes of two immiscible liquids, whose densities are ρ1 and ρ21 > ρ2), fill half the circle. The angle θ between the radius vector passing through the common interface and the vertical is :

(1) 

(2) 

(3) 

(4) 

Answer: (4)

3. 

In a meter bridge, as shown in the figure, it is given that resistance Y = 12.5 Ω and that the balance is obtained at a distance 39.5 cm from end A (by Jockey J). After interchanging the resistances X and , a new balance point is found at a distance l2 from end A. What are the values of X and l2?

(1)   19.15 Ω and 39.5 cm

(2)   8.16 Ω and 60.5 cm

(3)   19.15 Ω and 60.5 cm

(4)   8.16 Ω and 39.5 cm

Answer: (2)

4. An automobile, travelling 40 km/h, can be stopped at a distance of 40 m by applying brakes. If the same automobile is travelling at 80 km/h, the minimum stopping distance, in metres, is (assume no skidding) :

(1)   160 m

(2)   75 m

(3)   150 m

(4)   100 m

Answer: (1)

5. A given object takes n times more time to slide down a 45° rough inclined plane as it takes to slide down a perfectly smooth 45° The coefficient of kinetic friction between the object and the incline is :

(1) 

(2) 

(3) 

(4) 

Answer: (1)

6. A body of mass M and charge q is connected to a spring of spring constant k. It is oscillating along x-direction about its equilibrium position, taken to be at x = 0, with an amplitude A. An electric field E is applied along the x-direction. Which of the following statements is correct?

(1)   The new equilibrium position is at a distance 

(2)   The total energy of the system is 

(3)   The total energy of the system is 

(4)   The new equilibrium position is at a distance 

Answer: (3)

7. The relative error in the determination of the surface area of a sphere is α. Then the relative error in the determination of its volume is :

(1) 

(2)   α

(3) 

(4) 

Answer: (4)

8. A monochromatic beam of light has a frequency  and is propagating along the direction  It is polarized along thedirection. The acceptable form for the magnetic field is :

(1) 

(2) 

(3) 

(4) 

Answer: (2)

9. The energy required to remove the electron from a singly ionized Helium atom is 2.2 times the energy required to remove an electron from Helium atom. The total energy required to ionize the Helium atom completely is :

(1)   109 eV

(2)   34 eV

(3)   79 eV

(4)   20 eV

Answer: (3)

10. An ideal capacitor of capacitance 0.2 μF is charged to a potential difference of 10 V. The charging battery is then disconnected. The capacitor is then connected to an ideal inductor of self inductance 0.5 mH. The current at a time when the potential difference across the capacitor is 5 V, is :

(1)   0.34 A

(2)   0.17 A

(3)   0.25 A

(4)   0.15 A

Answer: (2)

11. A Carnot’s engine works as a refrigerator between 250 K and 300 K. It receives 500 cal heat from the reservoir at the lower temperature. The amount of work done in each cycle to operate the refrigerator is :

(1)   420 J

(2)   2520 J

(3)   772 J

(4)   2100 J

Answer: (1)

12. A planoconvex lens becomes an optical system of 28 cm focal length when its plane surface is silvered and illuminated from left to right as shown in Fig-A.

If the same lens is instead silvered on the curved surface and illuminated from other side as in Fig. B, it acts like an optical system of focal length 10 cm. The refractive index of the material of lens is :

(1)   1.75

(2)   1.50

(3)   1.55

(4)   1.51

Answer: (3)

13. Two electrons are moving with non-relativistic speeds perpendicular to each other. If corresponding de Broglie wavelengths are λ1 and λ­2, their de Broglie wavelength in the frame of reference attached to their centre of mass is :

(1) 

(2) 

(3)   λCM = λ1 = λ2

(4) 

Answer: (2)

14. Take the mean distance of the moon and the sun from the earth to be 0.4 × 106 km and 150 × 106 km respectively. Their masses are 8 × 1022 kg and 2 × 1030 kg respectively. The radius of the earth is 6400 km. Let ∆F1 be the difference in the forces exerted by the moon at the nearest and farthest points on the earth and ∆F2 be the difference in the force exerted by the sun at the nearest and farthest points on the earth. Then, the number closest to  is :

(1)   102

(2)   2

(3)   0.6

(4)   6

Answer: (2)

15. The equivalent capacitance between A and B in the circuit given below, is :

(1)   3.6 μF

(2)   4.9 μF

(3)   5.4 μF

(4)   2.4 μF

Answer: (4)

16. Light of wavelength 550 nm falls normally on a slit of width 22.0 × 105 The angular position of the second minima from the central maximum will be (in radians) :

(1)   π/6

(2)   π/4

(3)   π/8

(4)   π/12

Answer: (3)

17. A tuning fork vibrates with frequency 256 Hz and gives one beat per second with the third normal mode of vibration of an open pipe. What is the length of the pipe ? (Speed of sound in air is 340 ms1)

(1)   190 cm

(2)   200 cm

(3)   220 cm

(4)   180 cm

Answer: (2)

18. A body of mass m is moving in a circular orbit of radius R about a planet of mass M. At some instant, it splits into two equal masses. The first mass moves in a circular orbit of radius R/2, and the other mass, in a circular orbit of radius 3R/2. The difference between the final and initial total energies is :

(1) 

(2) 

(3) 

(4) 

Answer: (3)

19. In a screw gauge, 5 complete rotations of the screw cause it to move a linear distance of 0.25 cm. There are 100 circular scale divisions. The thickness of a wire measured by this screw gauge gives a reading of 4 main scale divisions and 30 circular scale divisions. Assuming negligible zero error, the thickness of the wire is :

(1)   0.3150 cm

(2)   0.4300 cm

(3)   0.2150 cm

(4)   0.0430 cm

Answer: (3)

20. A solution containing active cobalt  having activity of 0.8 μCi and decay constant λ is injected in an animal’s body. If 1 cm3 of blood is drawn from the animal’s body after 10 hrs of injection, the activity found was 300 decays per minute. What is the volume of blood that is flowing in the body? (1 Ci = 3.7 × 1010 decays per second and at t = 10 hrs e−λt = 0.84)

(1)   6 liters

(2)   5 liters

(3)   7 liters

(4)   4 liters

Answer: (2)

21. In the given circuit all resistances are of value R ohm each. The equivalent resistance between A and B is :

(1)   3R

(2)   2R

(3)   5R/3

(4)   5R/2

Answer: (2)

22. The velocity-time graphs of a car and a scooter are shown in the figure. (i) The difference between the distance travelled by the car and the scooter in 15 s and (ii) the time at which the car will catch up with the scooter are, respectively.

(1)   225.5 m and 10 s

(2)   112.5 m and 15 s

(3)   112.5 and 22.5 s

(4)   337.5 m and 25s

Answer: (3)

23. 

A uniform rod AB is suspended from a point X, at a variable distance x from A, as shown. To make the rod horizontal, a mass m is suspended from its end A. A set of (m, x) values is recorded. The appropriate variables that give a straight line, when plotted, are :

(1)   m, 1/x

(2)   m, x2

(3)   m, x

(4)   m, 1/x2

Answer: (1)

24. The number of amplitude modulated broadcast stations that can be accommodated in a 300 kHz band width for the highest modulating frequency 15 kHz will be :

(1)   8

(2)   15

(3)   10

(4)   20

Answer: (4)

25. A charge Q is placed at a distance a/2 above the centre of the square surface of edge as as shown in the figure

The electric flux through the square surface is :

(1)   Q/ϵ0

(2)   Q/6ϵ0

(3)   Q/2ϵ0

(4)   Q/3ϵ0

Answer: (2)

26. A Helmholtz coil has a pair of loops, each with N turns and radius R. They are placed coaxially at distance R and the same current I flows through the loops in the same direction. The magnitude of magnetic field at P, midway between the centres A and C, is given by [Refer to figure given below] :

(1) 

(2) 

(3) 

(4) 

Answer: (3)

27. A particle is oscillating on the X-axis with an amplitude 2 cm about the point x0 = 10 cm, with a frequency ω. A concave mirror of focal length 5 cm is placed at the origin (see figure).

Identify the correct statements.

(A)  The image executes periodic motion.

(B)  The image executes non-periodic motion.

(C)  The turning points of the image are asymmetric w.r.t. the image of the point at x = 10 cm.

(D)  The distance between the turning points of the oscillation of the image is 

(1)   (B), (D)

(2)   (B), (C)

(3)   (A), (D)

(4)   (A), (C), (D)

Answer: (4)

28. One mole of an ideal monoatomic gas is compressed isothermally in a rigid vessel to double pressure at room temperature, 27° The work done on the gas will be :

(1)   300 R ln 7

(2)   300 R ln 2

(3)   300 R

(4)   300 R ln 6

Answer: (2)

29. The B-H curve for a ferromagnet is sown in the figure. The ferromagnet is placed inside a long solenoid with 1000 turns/ cm. The current that should be passed in the solenoid to demagnetize the ferromagnet completely is :

(1)   20 μA

(2)   40 μA

(3)   2 mA

(4)   1 mA

Answer: (4)

30. A force of 40 N acts on a point B at the end of an L-shaped object, as shown in the figure. The angle θ that will produce maximum moment of the force about point A is given by :

(1)   tan θ = 2

(2)   tan θ = 4

(3)   tan θ = 1/2

(4)   tan θ = 1/4

Answer: (3)

CHEMISTRY

1. Which of the following statements about colloids is False?

(1)   When excess of electrolyte is added to colloidal solution, colloidal particle will be precipitated.

(2)   Colloidal particles can pass through ordinary filter paper.

(3)   When silver nitrate solution is added to potassium iodide solution, a negatively charged colloidal solution is formed.

(4)   Freezing pint of colloidal solution is lower than true solution at same concentration of a solute.

Answer: (4)

2. Ejection of the photoelectron from metal in the photoelectric effect experiment can be stopped by applying 0.5 V when the radiation of 250 nm is used. The work function of the metal is :

(1)   4.5 eV

(2)   5 eV

(3)   5.5 eV

(4)   4 eV

Answer: (1)

3. In which of the following reactions, an increase in the volume of the container will favour the formation of products?

(1)   2NO2(g) ⇌ 2NO(g) + O2(g)

(2)   4NH3(g) + 5O2(g) ⇌ 4NO(g) + 6H2O(l)

(3)   3O2(g) ⇌ 2O3(g)

(4)   H2(g) + I2(g) ⇌ 2HI(g)

Answer: (1)

4. When an electric current is passed through acidified water, 112 mL of hydrogen gas at N.T.P. was collected at the cathode in 965 seconds. The current passed, in ampere, is :

(1)   0.5

(2)   0.1

(3)   1.0

(4)   2.0

Answer: (3)

5. 

Answer: (4)

6. The decreasing order of bond angles in BF3, NH3, PF3 and I3 is :

(1)   I3 > NH3 > PF3 > BF3

(2)   BF3 > I3 > PF3 > NH3

(3)   BF3 > NH3 > PF3 > I3

(4)   I3 > BF3 > NH3 > PF3

Answer: (4)

7. In graphite and diamond, the percentage of p-characters of the hybrid orbitals in hybridization are respectively :

(1)   33 and 25

(2)   33 and 75

(3)   67 and 75

(4)   50 and 75

Answer: (3)

8. A sample of NaClO3 is converted by heat to NaCl with a loss of 0.16 g of oxygen. The residue is dissolved in water and precipitated as AgCl. The mass of AgCl (in g) obtained will be : (Given : Molar mass of AgCl = 143.5 g mol1)

(1)   0.54

(2)   0.41

(3)   0.48

(4)   0.35

Answer: (3)

9. N2O5 decomposes to NO2 and O2 and follows first order kinetics. After 50 minutes, the pressure inside the vessel increases from 50 mmHg to 8.75 mmHg. The pressure of the gaseous mixture after 100 minute at constant temperature will be :

(1)   116.25 mmHg

(2)   106.25 mmHg

(3)   136.25 mmHg

(4)   175.0 mmHg

Answer: (2)

10. Which of the following arrangements shows the schematic alignment of magnetic moments of antiferromagnetic substance?

(1) 

(2) 

(3) 

(4) 

Answer: (3)

11. The IUPAC name of the following compound is :

(1)   3-ethyl-4-methylhex-4-ene

(2)   4, 4-dithyl-3-methylbut-2-ene

(3)   4-methyl-3-ethylhex-4-ene

(4)   4-ethyl-3-methylhex-2-ene

Answer: (4)

12. For which of the following reactions, ∆H is equal to ∆U?

(1)   2HI(g) → H2(g) + I2(g)

(2)   2NO2(g) → N2O4 (g)

(3)   N2(g) + 3H2(g) → 2NH3(g)

(4)   2SO2(g) + O2(g) → 2SO3(g)

Answer: (1)

13. For Na+, Mg2+, F and O2 ; the correct order of increasing ionic radii is :

(1)   Na+ < Mg2+ < F < O2

(2)   Mg2+ < O2 < Na+ < F

(3)   Mg2+ < Na+ < F < O2

(4)   O2 < F < Na+ < Mg2+

Answer: (3)

14. The minimum volume of water required to dissolve 0.1 g lead (II) chloride to get a saturated solution (K­­sp of PbCl2 = 3.2 × 108; atomic mass of Pb = 207 u) is :

(1)   17.98 L

(2)   0.18 L

(3)   1.798 L

(4)   0.36 L

Answer: (2)

15. An ideal gas undergoes a cyclic process a show in Figure.

∆UBC = −5 kJ mol1, qAB = 2 kJ mol1

WAB = −5 kJ mol1, W­CA = 3 kJ mol1

Heat absorbed by the system during process CA is :

(1)   −5 kJ mol1

(2)   +5 kJ mol1

(3)   −18 kJ mol1

(4)   18 kJ mol1

Answer: (2)

16. The main reduction product of the following compound with NaBH4 in methanol is :

(1) 

(2) 

(3) 

(4) 

Answer: (2)

17. Which of the following will most readily give the dehydrohalogenation product?

(1) 

(2) 

(3) 

(4) 

Answer: (2)

18. The correct combination is :

(1)   [NiCl4]2 −square-planar ; [Ni(CN)4] 2 −paramagnetic

(2)   [NiCl4] 2 − diamagnetic; [Ni(CO)­4] −square-planar

(3)   [NiCl4] 2 − tetrahedral; [Ni(CO)­4] –paramagnetic

(4)   [NiCl4] 2 − paramagnetic; [Ni(CO)­4] –tetrahedral

Answer: (4)

19. Which of the following is a Lewis acid?

(1)   B(CH3)3

(2)   PH3

(3)   NF3

(4)   NaH

Answer: (1)

20. The copolymer formed by addition polymerization of styrene and acrylonitrile in the presence of peroxide is 

(1) 

(2) 

(3) 

(4) 

Answer: (3)

21. The major product of the following reaction is :

(1) 

(2) 

(3) 

(4) 

Answer: (2)

22. Xenon hexafluoride on partial hydrolysis produces compounds ‘X’ and ‘Y’ Compounds ‘X’ and ‘Y’ and the oxidation state of Xe are respectively :

(1)   XeOF4 (+6) and XeO3 (+6)

(2)   XeOF4 (+6) and XeO2F2 (+6)

(3)   XeO2F2 (+6) and XeO2 (+4)

(4)   XeO2 (+4) and XeO3 (+6)

Answer: (2)

23. The correct match between times of List-I and List-II is :

(1)   (A)-(R), (B)-(P), (C)-(S), (D)-(Q)

(2)   (A)-(R), (B)-(P), (C)-(Q), (D)-(S)

(3)   (A)-(P), (B)-(S), (C)-(R), (D)-(Q)

(4)   (A)-(R), (B)-(S), (C)-(P), (D)-(Q)

Answer: (2)

24. A white sodium salt dissolves readily in water to give a solution which is neutral to litmus. When silver nitrate solution is added to the aforementioned solution, a white precipitate is obtained which does not dissolve in dil. nitric acid. The anion is :

(1)   SO42

(2)   CO32

(3)   Cl

(4)   S2

Answer: (3)

25. In the molecular orbital diagram for the molecular ion, N2+, the number of electrons in the σ2p molecular orbital is :

(1)   2

(2)   1

(3)   0

(4)   3

Answer: (2)

26. The reagent (s) required for the following conversion are :

(1)   (i) B2H6  (ii) SnCl2/HCl       (iii) H3O+

(2)   (i) B2H6 (ii) DIBAL-H        (iii) H3O+

(3)   (i) LiAlH4 (ii) H3O+

(4)   (i) NaBH4 (ii) Raney Ni/H2 (iii) H3O+

Answer: (1)

27. Which of the following is the correct structure of Adenosine?

(1) 

(2) 

(3) 

(4) 

Answer: (1)

28. Identify the pair in which the geometry of the species is T-shape and square-pyramidal, respectively :

(1)   IO3 and IO2F2

(2)   XeOF2 and XeOF4

(3)   ICl2 and ICl5

(4)   ClF­3 and IO4

Answer: (2)

29. Which of the following will not exist in zwitter ionic from at pH = 7?

(1) 

(2) 

(3) 

(4) 

Answer: (2)

30. The increasing order of nitration of the following compounds is :

(1)   (a) < (b) < (d) < (c)

(2)   (b) < (a) < (d) < (c)

(3)   (b) < (a) < (c) < (d)

(4)   (a) < (b) < (c) < (d)

Answer: (1)

MATHEMATICS

1. Consider the following two binary relations on the set A = {a, b, c} :

R1 = {(c, a), (b, b), (a, c), (c, c), (b, c), (a, a)} and

R2 = {(a, b), (b, a), (c, c), (c, a), (a, a), (b, b), (a, c)}.

Then :

(1)   R1 is not symmetric but it is transitive.

(2)   both R1 and R2 are transitive.

(3)   both R1 and R­2 are not symmetric.

(4)   R2 is symmetric but it is not transitive.

Answer: (4)

2. A box ‘A’ contains 2 white, 3 red and 2 black balls. Another box ‘B’ contains 4 white, 2 red and 3 black balls. If two balls are drawn at random, without replacement, from a randomly selected box and one ball turns out to be white while the other ball turns out to be red, then the probability that both balls are drawn from box ‘B’ is :

(1)   7/16

(2)   7/8

(3)   9/32

(4)   9/16

Answer: (1)

3. An angle between the plane, x + y + z = 5 and the line of intersection of the planes, 3x + 4y + z – 1 = 0 and 5x + 8y + 2z + 14 = 0, is :

(1) 

(2) 

(3) 

(4) 

Answer: (4)

4. Two parabolas with a common vertex and with axes long x-axis and y-axis, respectively, intersect each other in the first quadrant. If the length of the latus rectum of each parabola is 3, then the equation of the common tangent to the two parabolas is :

(1)   x + 2y + 3 = 0

(2)   4(x + y) + 3 = 0

(3)   3(x + y) + 4 = 0

(4)   8(2x + y) + 3 = 0

Answer: (2)

5. If x1, x2, . . ., xn and  are two A.P.s such that x3 = h2 = 8 and x8 = h7 = 20, then x5∙h10 equals :

(1)   3200

(2)   2560

(3)   2650

(4)   1600

Answer: (2)

6. If (P ⋀ ~q) ⋀ (p ⋀ r) → ~ p ⋁ q is false, then the truth values of p, q and r are, respectively :

(1)   T, F, T

(2)   F, F, F

(3)   F, T, F

(4)   T, T, T

Answer: (1)

7. Let S be the set of all real values of k for which the system of linear equations

x + y + z = 2

2x + y – z = 3

3x + 2y + kz = 4

has a unique solution. Then S is :

(1)   an empty set

(2)   equal to R – {0}

(3)   equal to R

(4)   equal to {0}

Answer: (2)

8. The area (i9n sq. units) of the region {x ϵ R : x ≥ 0, y ≥ 0, y ≥ x – 2 and y ≤ √x}, is :

(1)   13/3

(2)   10/3

(3)   5/3

(4)   8/3

Answer: (2)

9. If the tangents drawn to the hyperbola 4y2 = x2 + 1 intersect the co-ordinate axes at the distinct points A and B, then the locus of the mid point of AB is :

(1)   x2 – 4y2 + 16x2y2 = 0

(2)   4x2 – y2 – 16x2y2 = 0

(3)   4x2 – y2 + 16x2y2 = 0

(4)   x2 – 4y2 – 16x2y2 = 0

Answer: (4)

10. If β is one of the angles between the normals to the ellipse, x2 + 3y2 = 9 at the points (3 cos θ, √3 sinθ) and (−3 sin θ, √3 cos θ);  then  is equal to :

(1)   √3/4

(2)   2/√3

(3)   √2

(4)   1/√3

Answer: (2)

11. If  are unit vectors such that  is equal to :

(1)   √15/4

(2)   √15/16

(3)   15/16

(4)   1/4

Answer: (1)

12. n-digit numbers are formed suing only three digits 2, 5 and 7. The smallest value of n for which 900 such distinct numbers can be formed, is :

(1)   9

(2)   6

(3)   7

(4)   8

Answer: (3)

13. If x2 + y2 + sin y = 4, then the value of  at the point (−2, 0) is :

(1)   −34

(2)   −32

(3)   4

(4)   −2

Answer: (1)

14. If tan A and tan B are the roots of the quadratic equation, 3x2 – 10x – 25 = 0, then the value of 3 sin2(A + B) – 10 sin(A + B) ∙ cos(A + B) – 25 cos2(A + B) is :

(1)   25

(2)   10

(3)   −25

(4)   −10

Answer: (3)

15. The value of the integral  is :

(1) 

(2)   3/4

(3) 

(4)   0

Answer: (1)

16. The set of all α ϵ R, for which  is a purely imaginary number, for all z ϵ C satisfying |z| = 1 and Re z ≠ 1 is :

(1)   equal to R

(2)   an empty set

(3)   {0}

(4) 

Answer: (3)

17. Let y = (x) be the solution of the differential equation  where

If y (0) = 0, the   is :

(1) 

(2) 

(3) 

(4) 

Answer: (4)

18. A variable plane passes through a fixed point (3, 2, 1) and meets x, y and z axes at A, B and C respectively. A plane is drawn parallel to yz-plane through A, a second plane is drawn parallel zx-plane through B and a third plane is drawn parallel to xy-plane through C. Then the locus of the point of intersection of these three planes, is :

(1) 

(2) 

(3) 

(4)   x + y + z = 6

Answer: (3)

19. The mean of a set of 30 observations is 75. If each observation is multiplied by a non-zero number λ and then each of them is decreased by 25, their mean remains the same. Then λ is equal to :

(1)   4/3

(2)   1/3

(3)   2/3

(4)   10/3

Answer: (1)

20. Let S = {λ, μ) ϵ R × R : f(t) = (|λ| e|t| − μ), sin (2|t|), t ϵ R, is a differentiable function}. Then S is a subset of :

(1)   R × (−∞, 0)

(2)   R × [0, ∞)

(3)   [0, ∞) × R

(4)   (−∞, 0) × R

Answer: (2)

21. If n is the degree of the polynomial, and m is the coefficient of xn in it, then the ordered pair (n, m) is equal to :

(1)   (12, (20)4)

(2)   (8, 5(10)4)

(3)   (24, (10)8)

(4)   (12, 8(10)4)

Answer: (1)

22. An aeroplane flying at a constant speed, parallel to the horizontal ground, √3 km above it, is observed at an elevation of 60° from a point on the ground. If, after five seconds, its elevation from the same point, is 30°, then the speed (in km/hr) of the aeroplane, is :

(1)   750

(2)   1440

(3)   1500

(4)   720

Answer: (2)

23. If b is the first term of an infinite G.P. whose sum is five, then b lies in the interval :

(1)   [10, ∞)

(2)   (−∞, −10]

(3)   (−10, 0)

(4)   (0, 10)

Answer: (4)

24. Let A be a matrix such that  is a scalar matrix and |3A| = 108. Then A2 equals :

(1) 

(2) 

(3) 

(4) 

Answer: (2)

25. If a right circular cone, having maximum volume, is inscribed in a sphere of radius 3 cm, then the the curved surface area (in cm2) of this cone is :

(1)   8√3 π

(2)   8√2 π

(3)   6√2 π

(4)   6√3 π

Answer: (1)

26. If  then 

(1)   does not exist.

(2)   exists and is equal to 0.

(3)   exists and is equal to 2.

(4)   exists and is equal to −2.

Answer: (4)

27. If λ ϵ R is such that the sum of the cubes of the roots of the equation, x2 + (2 – λ)x + (10 – λ) = 0 is minimum, then the magnitude of the difference of the roots of this equation is :

(1)   4√2

(2)   20

(3)   20√5

(4)   2√7

Answer: (3)

28. A circle passes through the points (2, 3) and (4, 5). If its centre lies on the line, y – 4x + 3 = 0, then its radius is equal to :

(1)   2

(2)   √2

(3)   √5

(4)   1

Answer: (1)

29. In a triangle ABC, coordinates of A are (1, 2) and the equations of the medians through B and C are respectively, x + y = 5 and x = 4. Then area of ∆ABC (in sq. units) is :

(1)   12

(2)   4

(3)   5

(4)   9

Answer: (4)

30. If  then ∫f(x) dx is equal to :

(where C is a constant of integration)

(1)   12 loge |1 – x| − 3x + C

(2)   −12 loge |1 – x| + 3x + C

(3)   −12 loge |1 – x| − 3x + C

(4)   12 loge |1 – x| + 3x + C

Answer: (3)

JEE Main Offline Examination Held on 08-04-2018 Code A Question Paper With Answer Key

JEE Main Offline Examination Held on 08-04-2018 Code A

PART-A : PHYSICS 

1. The density of a material in the shape of a cube is determined by measuring three sides of the cube and its mass. If the relative errors in measuring the mass and length are respectively 1.5% and 1%, the maximum error in determining the density is

(1)   2.5%

(2)   3.5%

(3)   4.5%

(4)   6%

Answer: (3)

2. All the graphs below are intended to represent the same motion. One of them does it incorrectly. Pick it up.

(1) 

(2) 

(3) 

(4) 

Answer: (2)

3. Two masses m1= 5 kg and m2= 10 kg, connected by an inextensible string over a frictionless pulley, are moving as shown in the figure. The coefficient of friction of horizontal surface is 0.15. The minimum weight m that should be put on top of m2 to stop the motion is

(1)   18.3 kg

(2)   27.3 kg

(3)   43.3 kg

(4)   10.3 kg

Answer: (2)

4. A particle is moving in a circular path of radius a under the action of an attractive potential  Its total energy is

(1) 

(2) 

(3)   Zero

(4) 

Answer: (3)

5. In a collinear collision, a particle with an initial speed v0 strikes a stationary particle of the same mass. If the final total kinetic energy is 50% greater than the original kinetic energy, the magnitude of the relative velocity between the two particles, after collision, is

(1) 

(2) 

(3) 

(4) 

Answer: (2)

6. Seven identical circular planar disks, each of mass M and radius R are welded symmetrically as shown. The moment of inertia of the arrangement about the axis normal to the plane and passing through the point P is

(1) 

(2) 

(3) 

(4) 

Answer: (4)

7. From a uniform circular disc of radius R and mass 9M, a small disc of radius R/3 is removed as shown in the figure. The moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through centre of disc is

(1)   4MR2

(2) 

(3)   10MR2

(4) 

Answer: (1)

8. A particle is moving with a uniform speed in a circular orbit of radius R in a central force inversely proportional to the nth power of R. If the period of rotation of the particle is T, then

(1)   T ∝ R3/2  for any n

(2) 

(3)   T ∝ R(n + 1)/2

(4)   T ∝ Rn/2

Answer: (3)

9. A solid sphere of radius r made of a soft material of bulk modulus K is surrounded by a liquid in a cylindrical container. A massless piston of area of a floats on the surface of the liquid, covering entire cross-section of cylindrical container. When a mass m is placed on the surface of the piston to compress the liquid, the fractional decrement in the radius of the sphere, (dr/r), is

(1) 

(2) 

(3) 

(4) 

Answer: (3)

10. Two moles of an ideal monoatomic gas occupies a volume V at 27°C. The gas expands adiabatically to a volume 2 V. Calculate (a) the final temperature of the gas and (b) change in its internal energy.

(1)   (a) 189 K         (b) 2.7 kJ

(2)   (a) 1195 K       (b) −2.7 kJ

(3)   (a) 189 K                   (b) −2.7 kJ

(4)   (a) 195 K                   (b) 2.7 kJ

Answer: (3)

11. The mass of a hydrogen molecule is 3.32 × 10−27 If 1023 hydrogen molecules strike, per second, a fixed wall of area 2 cm2 at an angle of 45° to the normal, and rebound elastically with a speed of 103 m/s, then the pressure on the wall is nearly

(1)   2.34 × 103 N/m2

(2)   4.70 × 103 N/m2

(3)   2.35 × 102 N/m2

(4)   4.70 × 102 N/m2

Answer: (1)

12. A silver atom in a solid oscillates in simple harmonic motion in some direction with a frequency of 1012/second. What is the force constant of the bonds connecting one atom with the other? (Mole wt. of silver = 108 and Avagadro number = 6.02 × 1023 gm mole−1)

(1)   6.4 N/m

(2)   7.1 N/m

(3)   2.2 N/m

(4)   5.5 N/m

Answer: (2)

13. A granite rod of 60 cm length is clamped at its middle point and is set into longitudinal vibrations. The density of granite is 2.7 × 103 kg/m3 and its Young’s modulus is 9.27 × 1010 What will be the fundamental frequency of the longitudinal vibrations?

(1)   5 kHz

(2)   2.5 kHz

(3)   10 kHz

(4)   7.5 kHz

Answer: (1)

14. Three concentric metal shells A, B and C of respective radii a, b and c (a < b < c) have surface charge densities +σ, −σ and + σ respectively. The potential of shell B is

(1) 

(2) 

(3) 

(4) 

Answer: (2)

15. A parallel plate capacitor of capacitance 90 pF is connected to a battery of emf 20 V. If a dielectric material of dielectric constant K = 5/3 is inserted between the plates, the magnitude of the induced charge will be

(1)   1.2 nC

(2)   0.3 nC

(3)   2.4 nC

(4)   0.9 nC

Answer: (1)

16. In an a.c. circuit, the instantaneous e.m.f. and current are given by

e = 100 sin 30t

In one cycle of a.c., the average power consumed by the circuit and the wattless current are, respectively

(1)   50, 10

(2) 

(3) 

(4)   50, 0

Answer: (2)

17. Two batteries with e.m.f 12 V and 13 V are connected in parallel across a load resistor of 10 Ω. The internal resistances of the two batteries are 1 Ω and 2 Ω respectively. The voltage across the load lies between

(1)   11.6 V and 11.7 V

(2)   11.5 V and 11.6 V

(3)   11.4 V and 11.5 V

(4)   11.7 V and 11.8 V

Answer: (2)

18. An electron, a proton and an alpha particle having the same kinetic energy are moving in circular orbits of radii re, rp, rα respectively in a uniform magnetic field B. The relation between re, rp, rα is

(1)   r­e > rp = rα

(2)   re < rp = rα

(3)   re < rp < rα

(4)   re < rα < rp

Answer: (2)

19. The dipole moment of a circular loop carrying a current I, is m and the magnetic field at the centre of the loop is B1. When the dipole moment is doubled by keeping the current constant, the magnetic field at the centre of the loop is B2. The ratio B1/B2 is

(1)   2

(2) 

(3) 

(4) 

Answer: (3)

20. For an RLC circuit driven with voltage of amplitude vm and frequency  the current exhibits resonance. The quality factor, Q is given by

(1) 

(2) 

(3) 

(4) 

Answer: (1)

21. An EM wave from air enters a medium. The electric fields are  in air and  in medium, where the wave number k and frequency ν refer to their values in air. The medium is non-magnetic. If  refer to relative permittivities of air and medium respectively, which of the following options is correct?

(1) 

(2) 

(3) 

(4) 

Answer: (3)

22. Unpolarized light of intensity I passes through an ideal polarizer A. Another identical polarizer B is placed behind A. The intensity of light beyond B is found to be I/2. Now another identical polarizer C is placed between A and B. The intensity beyond B is now found to be I/8. The angle between polarizer A and C is

(1)   0°

(2)   30°

(3)   45°

(4)   60°

Answer: (3)

23. The angular width of the central maximum in a single slit diffraction pattern is 60°. The width of the slit is 1 μm. The slit is illuminated by monochromatic plane waves. If another slit of same width is made near it, Young’s fringes can be observed on a screen placed at a distance 50 cm from the slits. If the observed fringe width is 1 cm, what is slit separation distance?

(i.e. distance between the centres of each slit.)

(1)   25 μm

(2)   50 μm

(3)   75 μm

(4)   100 μm

Answer: (1)

24. An electron from various excited states of hydrogen atom emit radiation to come to the ground state. Let λn, λg be the de Broglie wavelength of the electron in then nth state and the ground state respectively. Let Λn be the wavelength of the emitted photo in the transition from the nth state to the ground state. For large n, (A, B are constants)

(1) 

(2)   Λn ≈ A + Bλn

(3) 

(4) 

Answer: (1)

25. If the series limit frequency of the Lyman series is νL, then the series limit frequency of the P fund series is

(1)   25 νL

(2)   16 νL

(3)   νL/16

(4)   νL/25

Answer: (4)

26. It is found that if a neutron suffers an elastic collinear collision with deuterium at rest, fractional loss of its energy is pd; while for its similar collision with carbon nucleus at rest, fractional loss of energy is pd and pc are respectively

(1)   (.89, .28)

(2)   (.28, .89)

(3)   (0, 0)

(4)   (0, 1)

Answer: (1)

27. The reading of the ammeter for a silicon diode in the given circuit is

(1)   0

(2)   15 mA

(3)   11.5 mA

(4)   13.5 mA

Answer: (3)

28. A telephonic communication service is working at carrier frequency of 10 GHz. Only 10% of it is utilized for transmission. How many telephonic channels can be transmitted simultaneously if each channel requires a bandwidth of 5 kHz?

(1)   2 × 103

(2)   2 × 104

(3)   2 × 105

(4)   2 × 106

Answer: (3)

29. In a potentiometer experiment, it is found that no current passes through the galvanometer when the terminals of the cell are connected across 52 cm of the potentiometer wire. If the cell is shunted by a resistance of 5 Ω, a balance is found when the cell is connected across 40 cm of the wire. Find the internal resistance of the cell.

(1)   1 Ω

(2)   1.5 Ω

(3)   2 Ω

(4)   2.5 Ω

Answer: (2)

30. On interchanging the resistances, the balance point of a meter bridge shifts to the left by 10 cm. The resistance of their series combination is 1 kΩ. How much was the resistance on the left slot before interchanging the resistances?

(1)   990 Ω

(2)   505 Ω

(3)   550 Ω

(4)   910 Ω

Answer: (3)

PART-B : CHEMISTRY

31. The ratio of mass percent of C and H of an organic compound (CXHYOZ) is 6 : 1. If one molecule of the above compound (CXHYOZ) contains half as much oxygen as required to burn one molecule of compound CXHY completely CO2 and H2 The empirical formula of compound CXHYOZ is

(1)   C3H6O3

(2)   C2H4O

(3)   C3H4O2

(4)   C2H4O3

Answer: (4)

32. Which type of ‘defect’ has the presence of cations in the interstitial sites?

(1)   Schottky defect

(2)   Vacancy defect

(3)   Frenkel defect

(4)   Metal deficiency defect

Answer: (3)

33. According to molecular orbital theory, which of the following will not be a viable molecule?

(1) 

(2) 

(3) 

(4) 

Answer: (4)

34. Which of the following lines correctly show the temperature dependence of equilibrium constant K, for an exothermic reaction?

(1)   A and B

(2)   B and C

(3)   C and D

(4)   A and D

Answer: (1)

35. The combustion of benzene (l) gives CO2 (g) and H2­O(I). Given that heat of combustion of benzene at constant volume is –3263.9 kJ mol−1 at 25°C; heat of combustion (in kJ mol−1) of benzene at constant pressure will be

(R = 8.314 JK−1 mol−1)

(1)   4152.6

(2)   −452.46

(3)   3260

(4)   −3267.6

Answer: (4)

36. For 1 molal aqueous solution of the following compounds, which one will show the highest freezing point?

(1)   [Co(H2O)6]Cl3

(2)   [Co(H2O)5Cl]Cl2 ∙ H2O

(3)   [Co(H2O)4Cl2]Cl ∙ 2H2O

(4)   [Co(H2O)3Cl3] ∙ 3H2O

Answer: (4)

37. An aqueous solution contains 0.10 M H2S and 0.20 M HCl. If the equilibrium constant for the formation of HS from H2S is 1.0 × 10−7 and that of S2− from HS ions is 1.2 × 10−13 then the concentration of S2− ions in aqueous solution is

(1)   5 × 10−8

(2)   3 × 10−20

(3)   6 × 10−21

(4)   5 × 10−19

Answer: (2)

38. An aqueous solution contains an unknown concentration of Ba2+. When 50 mL of a 1 M solution of Na2SO4 is added, BaSO4 just begins to precipitate. The final volume is 500 mL. The solubility product of BaSO4 is 1 × 10−10. What is original concentration of Ba2+?

(1)   5 × 10−9 M

(2)   2 × 10−9 M

(3)   1.1 × 10−9 M

(4)   1.0 × 10−10 M

Answer: (3)

39. At 518°C, the rate of decomposition of a sample of gaseous acetaldehyde, initially at a pressure of 363 torr, was 1.00 torr s−1 when 5% had reacted and 0.5 torr s−1 when 33% had reacted. The order of the reaction is

(1)   2

(2)   3

(3)   1

(4)   0

Answer: (1)

40. How long (approximate) should water be electrolysed by passing through 100 amperes current so that the oxygen released can completely burn 27.66 g of diborane? (Atomic weight of B = 10.8 u)

(1)   6.4 hours

(2)   0.8 hours

(3)   3.2 hours

(4)   1.6 hours

Answer: (3)

41. The recommended concentration of fluoride ion in drinking water is up to 1 ppm as fluoride ion is required to make teeth enamel harder by converting [3Ca3(PO4)2 . Ca(OH)2] to

(1)   [CaF2]

(2)   [3(CaF2). Ca(OH)2]

(3)   [3Ca3(PO4)2. CaF2]

(4)   [3{Ca(OH)2}. CaF2]

Answer: (3)

42. Which of the following compounds contain(s) no covalent bond(s)?

KCl, PH3, O2, B2H6, H2SO4

(1)   KCl, B2H6, PH3

(2)   KCl2, H2SO4

(3)   KCl

(4)   KCl, B2H2

Answer: (3)

43. Which of the following are Lewis acids?

(1)   PH3 and BCl3

(2)   AlCl3 and SiCl4

(3)   PH3 and SiCl4

(4)   BCl3 and AlCl3

Answer: (4)

44. Total number of lone pair of electron in  ion is

(1)   3

(2)   6

(3)   9

(4)   12

Answer: (3)

45. Which of the following salts is the most basic in aqueous solution?

(1)   Al(CN)3

(2)   CH3COOK

(3)   FeCl3

(4)   Pb(CH3COO)2

Answer: (2)

46. Hydrogen peroxide oxidises [Fe(CN)6]4− to [Fe(CN)6] 3− in acidic medium but reduces [Fe(CN)6] 3− to [Fe(CN)6] 4− in alkaline medium. The other product formed are, respectively.

(1)   (H2O + O2) and H2O

(2)   (H2O + O2) and (H2O + OH)

(3)   H2O and (H2O + O2)

(4)   H2O and (H2O + OH)

Answer: (3)

47. The oxidation states of

Cr in [Cr(H2O)6]Cl3, [Cr(C6H6)2], and K2[Cr(CN)2(O)2 (NH3)] respectively are

(1)   +3 , +4 and +6

(2)   +3, +2, and +4

(3)   +3, 0and +6

(4)   +3, 0 and +4

Answer: (3)

48. The compound that does not produce nitrogen gas by the thermal decomposition is

(1)   Ba(N3)2

(2)   (NH4)2Cr2O7

(3)   NH4NO2

(4)   (NH4)2SO4

Answer: (4)

49. When metal ‘M’ is treated with NaOH, a white gelatinous precipitate ‘X’ is obtained, which is soluble in excess of NaOH. Compound ‘X’ when heated strongly gives an oxide which is used in chromatography as an adsorbent. The metal ‘M’ is

(1)   Zn

(2)   Ca

(3)   Al

(4)   Fe

Answer: (3)

50. Consider the following reaction and statements

[Co(NH3)4Br2]+ + Br → [Co(NH3)3Br3] + NH3

(I) Two isomers are produced if the reactant complex ion is a cis-isomer

(II) Two isomers are produced if the reactant complex ion is a trans-isomer.

(III) Only one isomer is produced if the reactant complex ion is a trans-isomer.

(IV) Only one isomer is produced if the reactant complex ion is a cis-isomer.

The correct statements are:

(1)   (I) and (II)

(2)   (I) and (III)

(3)   (III) and (IV)

(4)   (II) and (IV)

Answer: (2)

51. Glucose on prolonged heating with HI gives

(1)   n-Hexane

(2)   1-Hexene

(3)   Hexanoic acid

(4)   6-iodohexanal

Answer: (1)

52. The trans-alkenes are formed by the reduction of alkynes with

(1)   H2 – Pd/C, BaSO4

(2)   NaBH4

(3)   Na/liq. NH3

(4)   Sn – HCl

Answer: (3)

53. Which of the following compounds will be suitable for Kjeldahl’s method for nitrogen estimation?

(1) 

(2) 

(3) 

(4) 

Answer: (2)

54. Phenol on treatment with CO2 in the presence of NaOH followed by acidification produces compound X as the major product. X on treatment with (CH3CO)2O in the presence of catalytic amount of H2SO4 produces

(1) 

(2) 

(3) 

(4) 

Answer: (1)

55. An alkali is titrated against an acid with methyl orange as indicator, which of the following is a correct combination?

Answer: (3)

56. The predominant form of histamine present in human blood is (pKa, Histidine = 6.0)

(1) 

(2) 

(3) 

(4) 

Answer: (4)

57. Phenol reacts with methyl chloroformate in the presence of NaOH to form product A. A reacts with Br2 to form product B. A and B are respectively

(1) 

(2) 

(3) 

(4) 

Answer: (3)

58. The increasing order of basicity of the following compound is

(1)   (a) < (b) < (c) < (d)

(2)   (b) < (a) < (c) < (d)

(3)   (b) < (a) < (d) < (c)

(4)   (d) < (b) < (a) < (c)

Answer: (3)

59. The major product formed in the following reaction is

(1) 

(2) 

(3) 

(4) 

Answer: (4)

60. The major product of the following reaction is

(1) 

(2) 

(3) 

(4) 

Answer: (2)

PART-C : MATHEMATICS

61. Two sets A and B are as under :

A = {(a, b) ∈ R × R : |a – 5| < 1 and |b – 5| < 1}

B = {(a, b) ∈ R × R : 4(a – 6)2 + 9(b – 5)2 ≤ 36},

then

(1)   B ⊂ A

(2)   A ⊂ B

(3)   A ∩ B = ϕ (an empty set)

(4)   Neither A ⊂ B nor B ⊂ A

Answer: (2)

62. Let S = {x ∈ R : x ≥ 0 and 2|√x – 3| + √x(√x – 6) + 6 = 0}. Then S :

(1)   Is an empty set

(2)   Contains exactly one element

(3)   Contains exactly two elements

(4)   Contains exactly four elements

Answer: (3)

63. If α, β ∈ C are the distinct roots, of the equation x2 – x + 1= 0, then α101 + β107 is equal to

(1)   −1

(2)   0

(3)   1

(4)   2

Answer: (3)

64. If  then the ordered pair (A, B) is equal to

(1)   (−4, −5)

(2)   (−4, 3)

(3)   (−4, 5)

(4)   (4, 5)

Answer: (3)

65. If the system of linear equations

x + ky + 3z = 0

3x + ky – 2z = 0

2x + 4y – 3z = 0

has a non-zero solution (x, y, z), then xz/y2 is equal to

(1)   –10

(2)   10

(3)   –30

(4)   30

Answer: (2)

66. From 6 different novels and 3 different dictionaries, 4 novels and 1 dictionary are to be selected and arranged in a row on a shelf so that the dictionary is always in the middle. The number of such arrangements is

(1)   At least 1000

(2)   Less then 500

(3)   At least 500 but less than 750

(4)   At least 750 but less than 1000

Answer: (1)

67. The sum of the co-efficients of all odd degree terms in the expansion of  is

(1)   −1

(2)   0

(3)   1

(4)   2

Answer: (4)

68. Let a1, a2, a3, …….., a49 be in A.P. such that

and a9 + a43 = 66.

If  then m is equal to

(1)   66

(2)   68

(3)   34

(4)   33

Answer: (3)

69. Let A be the sum of the first 20 terms and B be the sum of the first 40 terms of the series 12 + 2.22 + 32 + 2.42 + 52 + 2.62 + ….

If B – 2A = 100λ, then λ is equal to

(1)   232

(2)   248

(3)   464

(4)   496

Answer: (2)

70. For each t ∈ R, let [t] be the greatest integers less than or equal to t. Then 

(1)   Is equal to 0

(2)   Is equal to 15

(3)   Is equal to 120

(4)   Does not exist (in R)

Answer: (3)

71. Let S = {t ∈ R : f(x) = |x – π| ∙(|x| – 1)sin |x| is not differential at t}. Then the set S is equal to

(1)   ϕ (an empty set)

(2)   {0}

(3)   {π}

(4)   {0, π}

Answer: (1)

72. If the curves y2 = 6x, 9x2 + by2 = 16 intersect each other at right angles, then the value of b is

(1)   6

(2)   7/2

(3)   4

(4)   9/2

Answer: (4)

73. Let  x ∈ R – {−1, 0, 1}. If  then the local minimum value of h(X) is:

(1)   3

(2)   −3

(3)   −2√2

(4)   2√2

Answer: (4)

74. The integral  is equal to

(1) 

(2) 

(3) 

(4) 

Answer: (2)

75. Then value of  is :

(1)   π/8

(2)   π/2

(3)   4π

(4)   π/4

Answer: (4)

76. Let g(x) = cos x2, f(x) = √x, and α, β (α < β) be the roots of the quadratic equation 18x2 – 9πx + π2 = 0. Then the area (in sq. units) bounded by the curve y = (gof) (x) and the lines x = α, x = β and y = 0 is

(1) 

(2) 

(3) 

(4) 

Answer: (1)

77. Let y = y(x) be the solution of the differential equation  x ∈ (0, π. If  then y(π/6) is equal to : 

(1) 

(2) 

(3) 

(4) 

Answer: (3)

78. A straight line through a fixed point (2, 3) intersects the coordinate axes at distinct points P and Q. If O is the origin and the rectangle OPRQ is completed, then the locus of R is

(1)   3x + 2y = 6

(2)   2x + 3y = xy

(3)   3x + 2y = xy

(4)   3x + 2y = 6xy

Answer: (3)

79. Let the orthocentre and centroid of a triangle be A(–3, 5) and B(3, 3) respectively. If C is the circumcentre of this triangle, then the radius of the circle having line segment AC as diameter, is

(1)   √10

(2)   2√10

(3) 

(4) 

Answer: (3)

80. If the tangent at (1, 7) to the curve x2 = y – 6 touches the circle x2 + y2 + 16x + 12y + c = 0 then the value of c is

(1)   195

(2)   185

(3)   85

(4)   95

Answer: (4)

81. Tangent and normal are drawn at P(16, 16) on the parabola y2 = 16x, which intersect the axis of the parabola at A and B, respectively. If C is the centre of the circle through the points P, A and B and ∠CPB = θ, then a value of tan θ is

(1)   1/2

(2)   2

(3)   3

(4)   4/3

Answer: (2)

82. Tangents are drawn to the hyperbola 4x2 – y2 = 36 at the points P and Q. If these tangents intersect at the point T(0, 3) then the area (in sq. units) of ∆PTQ is

(1)   45√5

(2)   54√3

(3)   60√3

(4)   36√5

Answer: (1)

83. If L1 is the the line of intersection of the planes 2x – 2y + 3z – 2 = 0, x – y + z + 1 = 0 and L2 is the line of intersection of the planes x + 2y – z – 3 = 0, 3x – y + 2z – 1 = 0, then the distance of the origin from the plane containing the lines L1 and L2, is

(1) 

(2) 

(3) 

(4) 

Answer: (2)

84. The length of the projection of the line segment joining the points (5, –1, 4) and (4, –1, 3) on the plane, x + y + z = 7 is:

(1)   2/√3

(2)   2/3

(3)   1/3

(4) 

Answer: (4)

85. Let  be a vector coplanar with the vectors  If  is perpendicular to  is equal to

(1)   336

(2)   315

(3)   256

(4)   84

Answer: (1)

86. A bag contains 4 red and 6 black balls. A ball is drawn at random from the bag, its colour is observed and this ball along with two additional balls of the same colour are returned to the bag. If now a ball is drawn at random from the bag, then the probability that this drawn ball is red, is:

(1)   3/10

(2)   2/5

(3)   1/5

(4)   3/4

Answer: (2)

87. If  then the standard deviation of the 9 items x1, x2, …. ., x9 is

(1)   9

(2)   4

(3)   2

(4)   3

Answer: (3)

88. If sum of all the solutions of the equation  in [0, π] is kπ, then k is equal to :

(1)   2/3

(2)   13/9

(3)   8/9

(4)   20/9

Answer: (2)

89. PQR is a triangular park with PQ = PR = 200 m. A T.V. tower stands at the mid-point of QR. If the angles of elevation of the top of the tower at P, Q and R are respectively 45º, 30º and 30º, then the height of the tower (in m) is

(1)   100

(2)   50

(3)   100√3

(4)   50√2

Answer: (1)

90. The Boolean expression ~ (p ⋁ q) ⋁ (~ p ⋀ q) is equivalent to

(1)   ~p

(2)   p

(3)   q

(4)   ~q

Answer: (1)

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  • Candidates shall maintain perfect silence and attend to their Question Paper only.Any conversation or gesture or disturbance in the Examination Room/Hall shall be deemed as misbehaviour.
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