1. The problem statement, all variables and given/known data Starting from rest, a 5.85 kg block slides 2.07m down a rough 26.4degree incline. The coefficient of kinetic friction between the block and the incline is 0.427. The acceleration of gravity is 9.8m/s^2. Find the work done by the normal force. Answer in units of Joules. Here's my FBD. I know the formula for work is Fcos(theta)d. But I don't know how to find the angle for the normal force... If someone could help out, I would really appreciate it.