M.Sc. DEGREE EXAMINATION, NOVEMBER 2017
Second Semester
Physics
THERMODYNAMICS AND STATISTICAL PHYSICS
(CBCS 2014 onwards)
Time 3 Hours Maximum 75 Marks
Part A (10 x 2 20)
Answer all questions.
1. State Kelvin and Clausius statements of second law of
thermodynamics.
2. Define Helmholtz free energy and obtain the change in
Helmholtz free energy during an infinitesimal reversible
process.
3. Give the validity of Boltzmann transport equation.
4. Briefly illustrate Brownian motion.
5. Illustrating with an example define and differentiate
microstate and macrostate.
6. State the major differences between the three ensembles.
7. Distinguish M B E and F D statistics by taking
two particles and two cells.
8. State the basic postulates of the particles obeying B E
statistics.
9. State the important properties of photons.
Sub. Code
4MPH2C3
AFF-4865
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10. Mention the limitations in Einstein's theory of specific
heat of solids.
Part B x 5 25)
Answer all questions, choosing either or
11. State and explain the principle of increase in
entropy.
Or
Deduce universal Vander waal equation of state.
12. State and prove Boltzmann's H theorem.
Or
Derive diffusion equation in hydrodynamics.
13. How a system attains statistical equilibrium?
Or
State and prove principle of equipartition of energy.
14. Obtain an expression for the most probable
microstate obeying Bose Einstein statistics.
Or
Derive Sackur Tetrode equation from the
thermodynamic entropy of a perfect gas.
15. Obtain an expression for Fermi energy and
calculate the Fermi energy in eV for sodium
assuming that it has one free electron per atom.
Given density of Na 0.97 gcm-3 and atomic weight
of Na 23.
Or
AFF-4865
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Derive an expression for energy fluctuations in
canonical ensemble.
Part C 10 30)
Answer any three questions.
16. Give examples for second order phase transition. And
obtain the condition for equilibrium between two phases.
17. Calculate the probability of finding a molecule with
momentum p in the gas under equilibrium conditions as
Maxwell Boltzmann distribution function.
18. State and prove Liouville's theorem.
19. Deduce the equation of state of a quantum ideal gas
20. Describe in detail about Pauli's paramagentism and then
deduce the expression for paramagnetic susceptibility.
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