A crane lifts a 3 tonne (3000 kg) load through a vertical height of 18 m in 24 s.
Calculate:
(a) the work done on the load [3]
(b) the gain in gravitational potential energy of the load [1]
(c) the power output of the crane [2]
(d) the power input to the crane if the efficiency is 0.45. [2]
