Work And Energy...

A body is moved through a distance of 5 m in the following different ways. Maximum work is done against gravity when the body is

If the momentum of a body increases by 20%, the increase in its K.E. will be

Work done by centripetal force during circular motion is

What is the change in potential energy as a body climbs a distance h and descends a distance h/2? (Assuming g being constant)

A work of 2 milli Joules changes the speed of a moving body of mass 0.1 gram. The change in speed

Asha lifts a doll from the floor and places it on a table. If the weight of the doll is known, what else does one need to know in order to calculate the work Asha has done on the doll?

Two masses of 1 g and 4 g are moving with KE in the ratio 4 : 1. What is the ratio of their linear momenta?

A water fall is 84 m high. Assuming that half the KE of the falling water gets converted to heat, the rise in temperature of water is

A ball is dropped vertically from a height d above the ground. It hits the ground and bounces up vertically to a height d/2. Neglecting subsequent motion and air resistance, its velocity v varies with the height h above the ground as

There is a hemispherical bowl of radius 3m. A block of mass 10 kg slides from the rim of the bowl to the bottom. The velocity of the block at the bottom will be

a wheelbarrow is an example of a lever of

Which of the following does not represent a simple machine?

What is the power of a pump, which can pump 500 kg of water from a depth of 40 m? (Take g as 10 m/s².)

From a waterfall, water is pouring down at the rate of 100 kg per second on the blades of a turbine. If the height of the fall be 200 m, the power delivered to the turbine is (approximately) equal to

An engine develops 10 kW of power. How much time will it take to lift a mass of 400 kg to a height of 80 m? (g = 10 m/s²)

A tape-recorder records sound in the form of

A moving body need not have

Water is falling from the top of a high water fall. On falling,

A spring, which is initially in its unstretched condition, is first stretched by a length X and then again by a further length X. The work done in the first case is W₁ and that in the second case is W₂. Which of the following relations between W₁ and W₂ is correct?

A mass of 2 kg falls from a certain height onto a spring of force constant 625 N/m. If the total distance traveled by the mass, from its point of release to its final position, is 40 cm, then the spring is compressed by