A 15 kg uniform disk of radius R = 0.25 m has a string wrapped around it, and a m = 3.6 kg weight is hanging on the string. The system of the weight and disk is released from rest.
a) When the 3.6 kg weight is moving with a speed of 1.2 m/s, what is the kinetic energy of the entire system?
bIf the system started from rest, how far has the weight fallen?
c What is the angular acceleration at this point?

for a I got 7.94J and for b I got 0.225m, I just can't seem to get the answer for c. please help!

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