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LOYOLA COLLEGE (AUTONOMOUS), CHENNAI 600 034
B.Sc.DEGREE EXAMINATION -PHYSICS
SECOND SEMESTER APRIL 2018
PH 2505- MECHANICS
Date: 27-04-2018 Dept. No. Max. 100 Marks
Time: 01:00-04:00
PART A
Answer All Questions. (10 X 2 20 MARKS)
1. When will a compound pendulum have a minimum time period?
2. State Graham's law for diffusion of gases.
3. What are holonomic and non-holonomic constraints?
4. Write down the mathematical equation that describes D'Alembert's principle.
5. Calculate the diameter of a molecule of benzene, if ɳ=2.79x1019 molecules per c.c. and mean free path for benzene 2.2x10-6 cm.
6. Explain transport phenomena.
7. How does the internal energy of an ideal gas differ from that of a real gas?
8. Differentiate first and second order phase transition.
9. State the condition for most probable distribution.
10. State any two limitations of Maxwell-Boltzmann statistics.
PART B
Answer ANY FOUR Questions. x 7.5 30 marks)
11. Deduce the equation of continuity of flow. State Bernoulli's theorem and mention any two of its applications.
12. Discuss the application of Lagrange's equation to a bead sliding on a uniform rotating wire.
13. Derive an expression for thermal conductivity of a gas on the basis of kinetic theory of gases and state its relation to coefficient of viscosity.
14. Explain Joule-Thomson effect using the Maxwell's thermodynamical relations and prove its absence for a perfect gas.
15. Using Maxwell's law of distribution of speeds of molecules in a gas obtain expressions for average speed and root-mean square speed.
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PART C
Answer ANY FOUR questions x 12.5 50 marks)
16. Derive an expression for the time period of Bifilar pendulum which is suspended by equal and parallel strings. (12.5)
17. Obtain the Hamilton's equation of motion and discuss its application to describe the motion of a particle in a central force field. (12.5)
18. Derive an expression for the viscosity of a gas in terms of mean free path of its molecules. Show that it is independent of pressure but depends upon the temperature of the gas. Discuss the effect of pressure temperature on .
19. Derive Maxwell's four thermodynamical relations. Use one of these to obtain Clausius Clapeyron's latent heat equation.
20. Applying Maxwell-Boltzmann distribution show that the internal energy of an ideal monoatomic gas depends only on its temperature. Derive the Maxwell-Boltzmann law of distribution of speeds.