A 65.7 kg skateboarder is sliding down a 15 meter long incline. The incline is 7.50 meters tall. As he slides down he encounters 96.5 N of friction. How fast is the skateboarder moving at the bottom of the hill?
(by the way, check my maths!)
At the top of the incline he will have gravitational potential energy
Heat due to friction equal to the "work" done by friction:
So the Kinetic Energy "available" to move the skater at the bottom of the incline will be the initial potential energy minus the energy used to heat up the ramp: