Question

In the figure below, a constant force of magnitude 82.0 N is applied to a 2.55 kg shoe box at angle = 64.5°, causing the box to move up a frictionless ramp at constant speed. How much work is done on the box by a when the box has moved through vertical distance h = 0.180 m?

Answer 1

Since the applied force causes the box to move at a constant speed implies that there are no changes in KE => The work done by Fa = change in PE:
W(a) = mgh= 2.55•9.8•0.18 = 4.5 J.