LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

   B.Sc. DEGREE EXAMINATION – PHYSICS

FIFTH SEMESTER – NOVEMBER 2010

PH 5509/PH 5506/PH 3500 – OPTICS

 

 

 

Date : 03-11-10                     Dept. No.                                        Max. : 100 Marks

Time : 9:00 – 12:00

SECTION – A

Answer ALL questions.                                                                                                (10 × 2 = 20 marks)

1. What are nodal points and nodal planes?
2. Define the term dispersive power.
3. A biprism is placed at a distance of 4cm from a narrow slit illuminated by a sodium light of

wavelength 5890 ×10^-10m. The distance between the coherent sources is 0.06cm.  Find the

width of the fringes observed in an eyepiece placed at a distance of 80cm from the biprism.

4. What is meant by antireflective coating?
5. What is a zone plate?
6. Define resolving power of an optical instrument.
7. State Malus law.
8. Calculate the thickness of quarter-wave plate given that μ_e= 1.563, μ₀ = 1.543 and

λ = 6×10^-7cm.

9. What is meant by optical pumping? Mention any two methods of pumping.
10. What is meant by second harmonic generation?

 

SECTION – B

 

Answer any FOUR questions.                                                                                        (4 × 7.5 = 30 marks)

11. Derive the conditions for the combination of two narrow angled prisms to produce

dispersion without deviation.  Also mention its practical application.

12. (a) Explain how white and dark interface fringes are formed using white light in Lloyd’s

single mirror experiment.

(b) Light of wavelength 6000 falls normally on a thin wedge shaped film of refractive

index 1.45 forming fringes that are 1.8mm apart.  Find the angle of wedge.

13. Discuss the Fraunhofer diffraction due to a single slit.
14. How would you produce and detect circularly polarised light?
15. (a) What are the components of a laser?

(b) Describe Ruby laser and explain its working.

 

SECTION – C

Answer any FOUR questions.                                                                                    (4× 12.5 = 50 marks)

16. (a) Explain chromatic aberration. Derive the condition for achromatism of two lenses

separated by a distance.

(b) Two lenses of focal length 5cm and 2cm are placed at a certain distance apart.

Calculate the distance between the lenses if they form achromatic combination.

17. Describe the construction and working of Michelson’s interferometer. Explain how the

wavelength of a monochromatic source can be determined using this interferometer.

18. Discuss the Rayleigh’s Criterion for the limit of resolution. Obtain an expression for the

resolving power of a plane diffraction grating.

19. (a) Define specific rotation.

(b) Describe the working of a half shade polarimeter and explain how it is used to

determine the specific rotation of sugar.

20. Discuss Einstenis’s theory of stimulated absorption, spontaneous emission and stimulated

emission and hence deduce the conditions for laser action.

 

 

Go To Main page

Latest Govt Job & Exam Updates:

View Full List ...