
A crane is used to lift 200 kg load from ground to the height 20m in 10s. Efficiency of the crane is 70%. Calculate power of crane.

Important Questions on Work, Energy and Power



A uniform chain of mass and length is lying on the table such that its one-fifth part is hanging from the edge of the table. What minimum work is required to lift this part of the chain on the table?

The figure below shows a simple pendulum of mass 200 g and length 1 m. It is moved from position A to B. What is potential energy of the pendulum at B? Now pendulum is released from position B. What is its energy at A? What is the speed at A?

The figure below shows two masses of 1.5 kg and 1 kg attached with two weightless strings. If 1.5 kg mass is released from its position how much high 1 kg mass moves up? What is the speed of strike of 1.5 kg mass on the wall?
