The power of a motor pump is 5 kW. How much water per minute the pump an raise to height of 20 m ? Take` g = 10ms ^-2`.

Four men lift a 250 kg box to a height of 1 m and hold it without raising or lowering it.How much work is done in just holding it? (Take g=10ms^(-2)).

If a man lifts a load up with the help of rope such that it raises the load of mass 50 kg to a height of 20 m in 100 seconds. Find the power of man. (Take g = 10ms^-2 )

The bottom of a rectangular swimming tank is 25 m by 40m. Water is pumped into the tank at the rate of 500 cubic metres per minute. Find the rate at which the level of water in the tank is rising.

A bucket containing water is tied to a rope of length 2.5 m and rotated in a vertical circle in wuch a way that the winter in it does not spill,what is the minimum velocity of the bucket at which this happens and how many rotations per minutes is it making then?(Take g=10 m s^(-2) ).

How much momentum will a dumb-bell of mass 10 kg transfer to the floor if it falls from a height of 80 cm ? Take its downward acceleration to be 10 ms ^(-2) .

At a hydroelectric power plant, the water pressure head is at a height of 300 m and the water flow available is 100 m^3s^-1 . If the turbine generator efficiency is 60%, estimate the electric power available from the plant (g = 9.8 ms^-2) .

A stone is dropped from the top of a tower 500 m high into a pond of water at the base of the tower. When is the splash heard at the top ? Given, g = 10ms^-2 and speed of sound = 340 ms^-1 .