1. A planet is revolving around the sun in an elliptical orbit. The mass of planet is m, angular momentum of planet about sun is L, and length of semi major axis is a and eccentricity is e. Time period of revolution of planet is given by 2ma1+e (1) T = L (3) T = 2ma1-62 = L ma1-02 (2) T= = L ma1-6 (4) T = Tshiksh 2. Metallic disc of inner radius R and outer radius 2R is rotating with an angular speed co. What will be the electric potential difference that appears between the inner and outer periphery. The mass of electrons is m and charge is e. 2R R (1) 3mwR 26 mwR (3) (4) mwR 26 2mwR 3. Two sources of sound emitting sound of nearly equal wavelengths and 2 are fixed at A and B respectively. A listener moves with velocity u on the perpendicular bisector of line joining A and B. Then the number of beats heard by him per second when it is at distance 21 from A and B, is (Speed of sound = c) (1) (c)() 20 00 B (3) (C-3u)() (2) (20-4) (+-) (4) Zero 4. An ideal gas undergoes a thermodynamic process in which internal energy (U) of the gas depends on pressure (P) of the gas as = aP4, where a is a positive constant. Assuming gas to be monoatomic, the molar heat capacity of the gas for given process will be 3R (1) 3 (3) 4 9R 4 (2) 24 3 4R (4) 5. A vertical cylindrical vessel contains a half litre of water having column height of 60 cm. If the density and bulk modulus of water are 103 kg m-3 and 2 109 N m respectively, then the elastic deformation potential energy (approximately) of water, is (1) 1.8 J (3) 2.1 J (2) 1.5 J (4) 2.4 J