1. The problem statement, all variables and given/known data Find the acceleration of the system if the mass m1 is a disk with radius R rolling down an incline which makes an angle theta with the horizontal, and the disk is connected to a pulley with mass M and radius R, which is connected to a block m2 hanging from that pulley. The system will be rotating with the disk, down the incline. 2. Relevant equations Net Torque of pulley = R(T2-T1) = Iw Net torque of m1 = R(m1gsintheta) Net force in x = m1gsintheta - T1 = m1a Net force in y = m1gcostheta 3. The attempt at a solution I've solved this exact problem for a block sliding instead of a disk using three equations: net torque on pulley = R(T1-T2), T1 = m1(gsintheta - a), and T2 = m2(a + g). So I just used substitution and isolated a. But I don't know how a disk as opposed to a block would change this situation, help would be appreciated, I don't have any pictures unfortunately, but its a standard inclined plane problem with a real pulley and rolling disk.