Suppose that a man (60 kg) is standing in an elevator. The elevator accelerates upward from rest at `1m//s^(2)` for 2 sec then for further 10 sec it moves with the constant velocity and then decelerates at the same rate for 2 sec
(a) For the whole motion, how much work is done by the normal force on the man by the elevator floor?
(b) By man's weight
(c) what average power is delivered by the normal force for the whole motion
(d) What instantaneous power is delivered by the normal force at 7 sec ?
(e) at 13 sec ?

Answer

A, B, D