LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
B.Sc., DEGREE EXAMINATION – PHYSICS
SECOND SEMESTER – SUPPLEMENTARY – JUNE 2012
PH 2503 – MECHANICS
Date : 28-06-2012
Time : 2:00 - 5:00
Dept. No.
Max. : 100 Marks
PART A
Answer ALL questions:
(10 x 2 = 20 marks)
1. Define centre of oscillation.
2. Define diffusion.
3. Give any two applications of Bernoulli’s theorem.
4. State what constitutes a couple.
5. Define centre of pressure.
6. Define degrees of freedom.
7. Define constrains and give one example to understand constrain.
8. State Newton’s law of gravitation.
9. Define centre of mass.
10. Define gravitational potential.
PART B
Answer any FOUR questions:
(4 x 7.5 = 30 marks)
11. (a) Prove that the centers of suspension and centre of oscillations are
Interchangeable.
(3)
(b) Explain how periodic time is measured in a torsional pendulum.
(4.5)
12. (a) Give the relation between the time of diffusion and length of column.
(4)
(b) Water flows along a horizontal tube of which the cross section is not constant. Calculate
the change in pressure when the velocity of flow changes from 0.1 m/s to 0.2 m/s.
(3.5)
13. Derive centre of gravity of a solid tetrahedron.
(7.5)
14. (a) State the conservation theorem for linear momentum.
(5)
(b) Define generalized co ordinates and hence express the Cartesian co-ordinates as
a function of generalized coordinates.
15. (a) State the three laws formulated by Kepler.
(b) Explain how the density of earth can be obtained.
(2.5)
(3)
(4.5)
PART C
Answer any FOUR questions:
( 4 x 12.5 = 50 marks)
16. Determine the period of oscillation of a bifilar pendulum with two equal non- parallel threads.
17. State Bernoulli’s theorem and hence prove that for a horizontal motion of the liquid, the sum of
its static and dynamic pressures remain constant.
(10+2.5)
18. (a) Determine experimentally the metacentric height of a ship.
(8)
(b) A ship is of 20000 tons displacement. A load of 30 tons moved 50 meters across the deck
makes the ship tilt through (3/4)o . Calculate the metacentric height of the ship.
(4.5)
19. a) Obtain from Lagrange’s equations of motion for ahdonomie conservative system,
from D’Alembert’s principle.
(6.5)
b) Setup Lagrange’s equations of motion for Atwood’s machine and solve them.
20. (a) Derive Newton’s law of gravitation from Kepler’s law.
(b) Determine gravitational constant by Boy’s method.
$$$$$$$
(6)
(4)
(8.5)