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**ARGH this is giving me a headache....**

I was cruising along fine until rotational dynamics, which heck, I thought I understood fine anyways, but apparently I was wrong. Ok, one problem that's killing me is as follows:

A pulley(in the form of a uniform disk)with mass 79kg and radius .18m is attached to the ceiling and rotates with no friction about its pivot. Acceleration of gravity is 9.8m/s^2, masses are connected by massless cord. You have the pulley hanging from a cord which weighs 79kg(the pulley does, not the cord), on its left is hanging a 55kg weight, and 1.3m below it but hanging on the other side is a 31kg weight, the tension in cord running from the 31kg weight to the pulley is the goal here, and I'm stumped. I got the moment of inertia of the pulley as 1.2798, and was mostly kinda fumbling in the dark from there. I think T1(the tension I'm looking for)can be given by T1-mg=ma, so I need to find a, which I guess I can get from finding the angular acceleration, which is hurting me:(

Other stumping question...well, it's hard to describe, but you have 3 forces being exerted on a 7.2kg wheel, outer radius and an inner radius, and it wants the magnitude of the net torque, which I THOUGHT was easy, but obviously I need to do something with that mass, which I didn't, so I have no clue as well