# Sri Krishnadevaraya University II Year B.Sc Physics 2009 Model Question Paper

MODEL PAPER
II Year  B.Sc Degree Examinations
PHYSICS Paper – II Thermodynamics and Optics
[With Maths Combination]
[From 2009-2010]
[Max marks :100 ]
[  Time :3 Hours ]

Section – A
Answer any four of the following :
4 x 15=60 Marks
1. What are transport phenomena in gases? Derive an expression for the coefficient of  viscosity of a gas on the basis of kinetic theory.
2. Describe the working of Carnot’s engine and derive an expression for its efficiency. Calculate the efficiency of a reversible engine that operates between the temperatures 200°C and 120°C?
3. What is adiabatic demagnetization? How is this principle used in producing low temperatures?
4. Define Solar constant . Explain how it can be determined experimentally.
Calculate the surface area of tungsten filament of 100W electric bulb. The operating temperature of tungsten is 2450K and its emissivity is 0.3.
5. What is chromatic aberration? Derive the condition for achromatism when two lenses are (a) in contact and (b)separated by a distance.
6. Describe the Newton’s rings method for measuring the wavelength of monochromatic  light . Give necessary theory.
7. Explain, with necessary theory, how a plane diffraction grating is used in normal incidence position to measure the wavelengths of spectral lines in mercury spectrum. A grating has 15 cms of the surface ruled with 6000 lines per cm.What is the resolving power of the grating in the first order?
8. What are the important characteristics of laser radiation ? Explain the working of  He-Ne gas laser.
Section -B
Answer any five of the following : 5 x 8=40 Marks

9. Distinguish between average ,most probable and r.m.s. speeds of molecules in a gas.
10. Write a note on entropy and disorder.
11. State and explain Joule-Kelvin effect.
12. What is a black body? What are the salient features of black body radiation?
13. State Bose – Einstien distribution law. Give its mathematical expression.
14. Deduce the system matrix for a thick lens.
15. Write a note on astigmatism.
16.What is meant by phase change on reflection?
17. Write a short note on law of Malus.
18.  Describe the basic principle of holography.

PHYSICS
(With Mathematics Combination)
MODEL PAPER

SECTION – A
(Essay type questions - 4 x 15 = 60)

1. Total Questions : 8 to be given out of 8 questions, 4 to be answered.

SECTION – B
(short questions 5 x 8 = 40)
Two questions: 10 to be given out of 10 questions, 5 to be answered.
Note: Small problems may be added to two or three  essay question.

Practicals scheme of valuation

1. Formula and explanation of symbols - (5 marks)
2. Tabular forms with circuit diagram wherever necessary - (5 marks)
3. Observations - (15 marks)
4. Calculations and graphs - (8 marks)
5. Result - (2 marks)
6. Viva-voce - (5 marks)
7. Practical Record - (10 marks)

Total Marks - (50 marks)

The copy is approved by Chairman and Members of BOS in (UG) Physics on 20-6-2009