I'm trying to solve this problem, but keep going around and not getting the correct equation.(adsbygoogle = window.adsbygoogle || []).push({});

A wheel of radius R, mass M, and moment of inertia I is mounted on a frictionless horizontal axle. A light cord wrapped around the wheel supports a body of mass m. At time t=0, the body is let go and the wheel starts rotating.

Show that the angular acceleration of the wheel is:

[tex]\alpha\equiv\frac{g}{R+I/mR}[/tex]

I know that [tex]I\alpha=TR[/tex] where T is the tension in the chord

and [tex]T=mg-ma[/tex], and [tex]a=R\alpha[/tex]

But in trying to combine the equations something is not working out, I think I am missing something, but I can't figure out what. Please help.

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# Homework Help: Please Help with angular acceleration

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