Question

 A thin cylindrical ring starts from rest at a height h; = 81 m. The ring has a radius R= 46 cm and a mass M=9 kg. 

Part (a) Write an expression for the ring's initial energy at point 1, assuming that the gravitational potential energy at point 3 is zero.

Part (b) If the ring rolls (without slipping) all the way to point 2, what is the ring's energy at point 2 in terms of h, and v2? 

Part (c) Given h = 32 m, what is the velocity of the ring at point 2 in m/s?