1. The problem statement, all variables and given/known data I'm just working through a few past mechanics papers and this question came up: A belt drives the circumference of a cylindrical wheel of radius R and mass M with no slipping. The tension in the belt is T. Friction in the wheel bearing causes an effective torque N to act on the wheel. (i) If the velocity of the belt is constant, what is T in terms of N. (ii) The bearing is lubricated removing all significant friction and the velocity of the belt then increases with a uniform acceleration a. Write down T in terms of M, R, and a. I'd be greatful if someone could just check through my solutions so that i'm sure doing things correctly. 2. Relevant equations I=0.5mR^2 for disc v=wr L=I(dw/dt) 3. The attempt at a solution (i) T=N . (ii) v=wR implies dw/dt = a/R . Therefore TR = 0.5MR^2 * (a/R) , and so T = 0.5Ma . Thanks.