Nalanda Open University
Annual Examination 2016
B.Sc. Physics (Honours), Part-I
Paper-II
Time: 3.00 Hrs. Full Marks: 80
Answer any Five questions, selecting at least Two from each group. All questions carry equal marks.
Group A
1. Derive the expression for mean free path of gas molecules on the basis of Kinetic
theory of gases. How is this quantity experimentally determined?
2. Describe the Einstein's theory of Brownian Motion and obtain the expressiion for
average square displacement of a particle. Compare this with Langevin's theory of
Brownian motion.
3. State the principle applied by Planck for the energy of an oscillator. Derive Planck's
radiation formula and give its application.
4. Deduce an expression for steady state temperature distribution along a uniform metal rod
heated at one end.
5. State the principle of equipartition of energy and derive the result that the mean energy
of system of gases is ½kT per degree of freedom.
Group B
6. Derive the expression for efficiency of Carnot's engine using the laws of
thermodynamics. Define Carnot's refrigerator.
7. Derive Clausius-Clapeyron equation of 1st order phase transition and explain triple
point.
8. Write down Maxwell's equations in thermodynamics and apply then to solve at least two
simple physical problems.
9. Describe porous-plug experiment. What is Joule-Thomson effect?
10. What is thermodynamic probability Explain phase space representation of a particle.
Also, give the statistical Interpretation of the 2nd law of thermodynamics.