A man tries to lift a mass 200 kg with a force 100N. Is he doing work ? Explain.

A man tries to lift a mass 200 kg with a force 100N. If it is lifted to 2m in 10s find the power.

Recoil of a gun is based on the principle of conservation of momentum. A bullet of mass 100g is fired from a rifle of mass 200kg with a speed of 50 m//s . Calculate the recoil velocity of the rifle.

Force is required to lift a body from the ground to a height h and work is measured as the product of force and magnitude of displacement. A man of mass 60 kg carries a stone of mass 20 kg to the top of a multistoreyed building of height 50 m . Calculate the total energy spent by him? (g= 9.8 m/s^2)

According to Newton's law of motion,the force depends on the rate of change of momentum. A man jumping out of a moving bus with his head forward.What should he do in order to land safely?

Work is related to force and displacement over which it acts. A man tries to pull a rigid wall for long time but fails to displace it. What is the external work done by him?

A hydraulic lift is designed to lift a maximum, mass of 3000 kg and area of the piston carrying it is 425 cm^(2) . What is the maximum pressure \that should be applied to the smaller piston?