1. The problem statement, all variables and given/known data How much mechanical energy is lost to friction if a 58.1-kg skier slides down a ski slope at constant speed of 12.1 m/s? The slope is 122.3 m long and makes an angle of 10.3° with respect to the horizontal. 2. Relevant equations Emec=KE+PE 3. The attempt at a solution I first found the height of the slope by using sin. Then I tried calculating the difference in PE and KE but it was wrong. I don't know where to go from here.