A 10kilow walts electric motor is used to raise a 400kg load of bricks to a height of 60meters.The efficiency of the motor 80%.what is the input energy?

Answer 1

Work = F*h = Mg*h = 400*9.8 * 60 = 235,200 J. = Output energy.

Input energy = Output/Eff. = 235,200/0.8
= 294,000 J.