In Young's experiment ,light of wavelength 4000 A⁰ is used to produce bright fringes of width 0.6mm , at a dipped in a liquid of refractive index 1.5 , then the fringe width will be

1) 0.2mm
2) 0.3mm
3) 0.4mm
4) 1.2mm

A gaseous mixture contains 1 mole of a gas (γ=5/3)and another gas B (with γ=7/5) at a temperature T. Assuming that gases do not react with each other and behave ideally and γ for mixture is 19/13. The fraction of gas B in the mixture is

1) 2 / 3
2) 1 / 3
3) 1
4) 3 /4

Water falls from a height 500m. The rise in temperature of water at bottom if whole of the energy remains in water, will be ( specific heat of water is 4.2 kJ/kg)

1)0.23°C
2) 1.16°C
3)096°C
4)1.02°C

 A reel of mass less thread rolls itself falling down under gravity. The acceleration of its fall is

(1)     g                             (2)     g/2

(3)     2g/3                         (4)     4g/3

 A cart of mass has a block of mass m attached to it as shown in figure. The coefficient of friction between the block and the cart is µ. What is the minimum acceleration of the cart so that the block m does not fall

1)µg
2) g/µ
3)µ/g
4)Mµg/m

If the degrees of freedom of a gas are f, the ratio of its two specific heats, C_P/C_V, is given by:

1) 1 - (1/f)
2) 1 – (2/f)
3) 1 + (1/f)
4) 1 + (2/f)

Two radiations containing photons of energy twice and five times the work function of a metal one incident successively on the metal surface. The ratio of the maximum velocities of the emitted electrons in the two cases will be:

1).1 : 3
2).1 : 4
3).1 : 2
4).2 : 5

A bob is suspended from a crane by a cable of length l = 5m. The crane and load are moving at a constant speed v. the crane is stopped by a bumper and the bob on the cable swings out an angle of 60°. The initial speed v is ( g=9.8 m/s²)

1) 10 m/s
2) 7 m/s
3) 4 m/s
4) 2 m/s

 Ratio of De-Broglie wavelengths of a proton and an alpha particle of the same energy is :

(1) 1 : 4             (2) 4: 1

(3) 1: 2             (4) 2 : 1

A cube of aluminum has side length 0.10 m. It is dropped into a deep swimming pool of water with density 1.00 x 10³ kg/m³ . The cube comes gently to rest at the bottom of the pool. If the density of the aluminum is 2.7 x 10³  kg/m3 , the magnitude of the buoyant force acting on the aluminum is:

1) 26.6 N
2) 9.8 N
3) 2.7 N
4) 1.0 N