1. The problem statement An olympic skier moving at 20.0 m/s down a 30.0 degree slope encounters a region of wet snow and slides 145 m before coming to a halt. What is the coefficient of friction between the skis and the snow? 2. Relevant Equations Mk=Ff/Fn FdCosO=1/2MVf^2-1/2MVo^2 3. The attempt at a solution Drew free body diagram and identified the forces acting on the skier to be the normal force (Fn), gravity (mg), and Ff (frictional force). Fn and mg cancel each other out so the only other force to consider is Ff. I figured I could use the work/kinetic energy formula to find Ff then plug the answer into the formula for Mk. Problem is that I need the mass of the skier for my plan to work.