The pulley shown in the illustration has a radius of 2.70 m and a moment of inertia of 39.0 kg∙m2. The hanging mass is 4.20 kg and it exerts a force tangent to the edge of the pulley. What is the angular acceleration of the pulley? All I have so far is the force exerted on the pulley by the block mg = 4.2kg * 9.8m/s2 = 41.16N which means it exerts a torque of r * F = 2.7m * 41.16N = 111.13Nm I know net torque = moment of Inertia * angular acceleration, but I think I am missing another component of the net torque. What is that component and how do I find it?