A boy pulls a box of mass 48 kg with a force of 110 N at an angle of 28o above the horizontal. The coefficient of friction between the sled and the surface is 0.32. Find the work done.

Answer 1

The work done by the boy will be Fd cosθ regardless of the friction. Any excess work beyond the work against friction will go into kinetic energy. You need a displacement to solve the problem.