Answer:
E) The net work done by the two forces is zero joules.
Explanation:
As the elevator is moving at a constant speed, it is the same as being stationary. The tension in the cable perfectly balances the gravitational force. Work done by gravity = mgh
Work done by the tension = -Th
where, T = tension force. The negative sign comes as the direction of T is opposite to the direction of g. As the elevator moves at a constant speed, the magnitude of the two forces must be equal. Therefore, the total work done,
W = (mg - T)h = 0
