(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A string is wrapped around a uniform solid cylinder of radius R, cylinder can rotate freely about its axis. The loose end of the string is attached to a block. The block and cylinder each have mass, m.

Find the magnitude "alpha" of the angular acceleration of the cylinder as the block descends in terms of r, radius, and g, acceleration due to gravity.

2. Relevant equations

F=ma

F=mg-T

I x alpha= -rT

I=1/2mr^2

alpha= -a/r

3. The attempt at a solution

I've been trying to solve this system of equations to find alpha in terms of g and r, but everytime I do so, I end up with g and alpha cancelling out.

I keep ending up with -alpha x r = mg + 1/2r x alpha

I think perhaps I'm subsituting something incorrectly? Somebody want to lead me in the correct direction please??

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# Homework Help: Acceleration of a Pulley

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