The problem states: when the play button is pressed, a CD accelerates uniformly from rest to 450 rev/min in 3.0 revolutions. If the CD has a radius of 6.0-cm and a mass of 17-g, what is the torque exerted on it? I used the the forumla tau = I * alpha; I = .5(0.017)(0.06)^2 = 3.06E-5; in order to calculate alpha, I used wf^2 = wo^2+2alpha(theta); from this I get alpha = square root (wf^2)/(2*theta). I realize some converting is necessary so I convert 450 rev/min into 47.124 rad/s, and 3.0 revolutions into 18.50 rad. Applying these figures to solve for alpha, I get 60.018 rad/s^2. Finally, tau = I*alpha = 0.00184 N*m. This is incorrect. Can someone direct me in the right direction? Thanks in advance.