Two masses suspended from a pulley

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Homework Statement



hi, I am really stuck on this question:

Two masses m and M, M>m are joined by a massless inelastic string and suspended from a pulley of radius R and moment of inertia I. the pulley rotates about its centre freely with no friction. The system starts at t=0 from rest. during the motion of the system, the string does not slip on the pulley's rim.


Homework Equations



a) Find the acceleration of M. What sort of motion is produced?
b)Are the tensions on each side of the pulley the same? Do they vary with time? Find their magnitude(s) in terms of M, m, I and g.



The Attempt at a Solution



i have produced a free body diagram and come up with the following equations:

ma + Ma = mg + Mg - [T][/m] - [T][/M] (1)

Newton II (rotational ver) I(alpha) = TR (2)

and a = R(alpha)

im not sure where to go next, or if I am correct with these equations.
help would be muchly appreciated
 

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rusticle said:
i have produced a free body diagram and come up with the following equations:

ma + Ma = mg + Mg - [T][/m] - [T][/M] (1)

Newton II (rotational ver) I(alpha) = TR (2)

and a = R(alpha)
Your equations (1) and (2) are not quite right. Show how you got them. (I suggest writing a separate equation for each mass, so you end up with three equations.)
 
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