Bharathiar University 2000 M.Sc Physics Quantum Mechanics -II - Question Paper
Sunday, 24 March 2013 01:50Web
Page 1 of 5
Degree
I
281 . [9023 801
(For the candidates admitted from 1999 onwards) M.Sc. DEGREE EXAMINATION, NOfEMBlE 2000, Third Semester
Physics
quantum mechanics - II
Time: Three hours Maximum * 100 marks
; SECTION A - (10 x 2 = 20 marks)
.Answer ALL the questions.
Choose the correct answer:
1. la nuclear physics the scattering centres have linear dimensions of the order of
(a) 10- to, lO4 cm (b) KHto lOcm
(c) 1 <Htol(H*aa (d) 10"* to 10- cm,
2. Doublet separation
(a), eases witbincreasipg atomic timber * (b) decreases with iexeaaieg ztszdc atmber
(c) does not change with atomic number (i) none of the above.
3. la hydrogen molecule, the energy of dissod' ioa of the molecule into atoms is theoretically calculated to be.
(a) 1.76 eV . , 2.78 eV
4, Let An and Ba be Easterns coeffidenfs, then
V.
s21 c2
**21
fh) rMhv-: i} Ba C3
(c)
BM 8a: Ap3
(d) ASL_te*u*
c1 ;
5. The lerwering operator is
(a) (pimw x) (b) (p
(c) (imwx~p) (d) (pimmx).
Answer ALL questions in 1 or 2 sentences ;
S, Define Greens function.
7. What U meant by self-consistent field?
8. What is meant by hybridization?
9. Define Einsteins coefficients.
10. What is a field?
SECTION B {5 x 4 = 20 marks)
Answer All. questions, choosing either (a) or (b).
11. (a) Explain the terms differential scattering
cross-section and total scattering cross-section.
Or
(b) Explain briefly the condition for validity of Born's approsmation. ' ,
12. (ar What is meant by Central field approximation?
Or
. (b) Give an account of the terms .arising due to L-S coupling is complex ntoms. .
15. la) J&plam Briefly the term spin orbit intei action.
Or
(b) Write a note oa covalent bonding.
\ i
3 281
14, (a) Disfesguisli between spontaneous emit 'bn and induced emission.
Or
lb), Explain the term 'rasity matrix.
15, (a) Obtain Lagrange equation for classical field.
Or
(b) What ere creation, destruction and number operators?
SECTION C - (5 x 8 = 40 marks)
Answer ALL questions, choosing either Ca) or (b).
18. (a) Obtain an expression for the scattering
amplitude in terms of Greens function.
Or
(b) Discuss fully tie method of partial wates for scattering.
1?, (a) Give aa account of Hartrees self consistent field (S.C.F) method.
Or
(b) Discuss the doublet separation in alkali spectra.
18. (a) Give an account of the theory of hydrogen molecule ion and obtain expressions for symmetric and Miti-symmetiic energy states.
Or .
(b) Explain briefly hybridisation of atomic orbitals with an example,
19. (a) Obtain Einsteins transition probability coefficients for induced emission and absorption.
Or
(b) Discuss the interaction of an atom with electromagnetic radiation and find Le transition probability.
20. (a) Deduce quantum field equations.
' ' " Or'
(b) Describe fully quantization of non-relativistic
Sekrmimget equation.
5 281
SECTIOND (2x 10 = 20marks) ; ' Answer ALL qiiegtiens* choosing either (a) or ft).
21. (a) Deri-? an expression for scattering amplitude based oa Boms apprcdmation.
. . . Or .
(b) Gif aa accourt of the Thomas-Fermi
statistical model,
22, (a) Discuss felly Heitler-London theory of the hydrogen molecule.
Or '
(b) Obtain classical field equations in Hamiltonian form, - ' v,
Add comment
| Earning: Approval pending. |
|
|
