1. The problem statement, all variables and given/known data Starting from rest, a 5 kg block slides 2.5 m down a rough 30 degree incline. The coefficient of kinetic friction between the block and the incline is 0.436. The acceleration of gravity is 9.8 m/s2. Find the work done by the force of gravity. Find the work done by the normal force. 2. Relevant equations Wgravity = mgh 3. The attempt at a solution I figured out work done by force of gravity: Wgravity = (5 kg)(9.8 m/s2)(2.5sin30) = 61.25 J However, I don't know how to find the work done by the normal force. Is it the same as work done by gravity?