physics
posted by Luc .
In loading a lorry a man lifts boxes each of weight 100N throughta height of 1.5 m. a)how much work does he do in lifting 1 box b)how much energy is transferred when 1 box is lifted c)if he lifts 4 boxes/minute@ what power is he working

a. W = Fd = 100 * 1.5 = 150 Joules.
b. E = mgh = 100 * 1.5 = 150 Joules.
c. V = 4boxes/min * 1.5m/box * (1/60)min/s = 0.1m/s.
Po = FV = 100 * 0.1m/s = 10 Joules/s =
10 Watts.