LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034

B.Sc. DEGREE EXAMINATION – PHYSICS

CC 09

FIFTH SEMESTER – November 2008

PH 5504 – ATOMIC AND NUCLEAR PHYSICS

 

 

 

Date : 03-11-08                     Dept. No.                                        Max. : 100 Marks

Time : 9:00 – 12:00

SECTION – A

Answer All the questions.                                                                                           (10×2 = 20 Marks)

1. State and explain Pauli’s exclusion principle.
2. What is meant by spin-orbit interaction?
3. What are isobars? Give an example.
4. State Geiger – Nuttal law.
5. Explain briefly cross-section of reactions.
6. What do you know about the magnetic moment of a neutron?
7. What are hard and soft components of cosmic rays?
8. What are Hyperons?
9. What is meant by Nuclear Magnetic Resonance?
10. Define Relaxation time with respect to nuclear spin energy.

 

SECTION – B

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

 

11. Describe Dunnigton’s method for the determination of e/m of electron.
12. (a). Define: (i) Mass defect, (ii) Binding energy and  (iii) Packing fraction.            (4.5 marks)

 

(b) The masses of the hydrogen atom and of neutron are 1.008142 and 1.008982

amu respectively. Calculate the binding energy and packing fraction per nucleon

of  ¹⁶O nucleus if its atomic mass is 15.994915 amu.                                         (3 marks)

 

13. (a). Explain nuclear fission and chain reaction?                                     (5¹/₂ marks)

(b). When a U-235 nucleus undergoes fission, 200 MeV energy is released. How much energy

in joules will be released when 1 g of U –235 is fissioned?                                          (2 marks)

 

14. What are cosmic ray showers? Discuss qualitatively the mechanism of their origin.
15. What is Mössbauer effect? Explain the experimental arrangement to study Mössbauer effect.

 

SECTION – C

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

16. (a) What is Compton effect? Derive an expression for the change in wavelength of the scattered

photon using quantum theory.                                                                              (10.5 marks)

(b)  Calculate the Compton wavelength.                                                                     (2 marks)

17. (a) Give an account of the β – ray spectrum. Explain the neutrino hypothesis to understand the spectrum.                                                 (10 marks)

(b) Explain inverse β – decay.                                                                                      (2.5 marks)

18. How was neutron discovered? Give an account of its properties and also production and detection techniques.
19. Describe the liquid drop model of the nucleus. Obtain an expression for the binding energy of a nucleus on the basis of semi-empirical mass formula of Weizsäcker.
20. Explain, in detail, the characteristics of NMR spectra.

 

Go To Main page

 

 

 

 

 

Latest Govt Job & Exam Updates:

View Full List ...