A labour lifts 100 stones to a height of 6m in two minutes. If mass of each stone be 1kg, calculate the average power of the labourer. Take g=`10ms^(-1)1`.

A crane lifts a mass of 100 kg to a height of 10m in 20s . The power of the crane is (Take g = 10 ms^(-2))

A crane lifts a mass of 100 kg to a height of 10 m in 20 s. The power of the crane is (Take g = 10 m s^(-2) )

A person lifts a stone of mass 100 g from the ground to a height of 1.5 m and projects it with a speed 4 m/s . If the process takes 1.5 s then calculate power of the person .

A solid disc of mass M is just held in air horizontally by throwing 40 stones per sec vertically upwards to strike the disc each with a velocity 6 ms^(-1) . If the mass of each stone is 0.05kg what is the mass of the disc (g=10ms^(-2))

A body of mass 1000 kg is lifted up by a crane through a distance 15 min 1 minute. A second crane does the same job in two minute. What is the amount of work done by each crane and what is the ratio of their powers? (g=10m//s^(2))

An elevator in a building is designed to carry a load of 5000 kg throgh 10 floors . If height of each floor is 5 cm on an average and it takes 8 seconds to climb 10 floors , calculate the horse power of the lift .