Sam, whose mass is 73.0kg , takes off down a 50.0m high, 12.0∘ slope on his jet-powered skis. The skis have a thrust of 210N . Sam's speed at the bottom is 45.0m/s . What is the coefficient of kinetic friction of his skis on the snow?

Answer 1

energy going into his KE-energy going into friction=final KE

mg50+210*50/cos12 - mgcos12*mu=1/2 m 45^2

notice mass divides out, you are left with an expression, solve for mu.