A metal ring having an outside radius of 38.0 cm, and an inside radius of 30.5 cm, has a mass of 15.0 kg. The ring falls off the back of a speeding truck, and rolls without slipping at a speed of 45.0 Km/hr.
A. What is the moment of inertia of the ring?
B. What is the total kinetic energy of the ring?
C. If friction causes the ring to stop in 500m, how much work did friction do?