A cylinder of mass m and radius R is rigidly mounted to the same shaft as a lightweight cylinder of radius R/2. The shaft is free to turn with negligible friction. Cords are wound in opposite directions about the cylinders, and identical masses m are hung from the cords. a) Which way do the cylinders turn? (clockwise) b) what is the acceleration of the mass hung on the cylinder of radius R?(adsbygoogle = window.adsbygoogle || []).push({});

The actual problem comes with a picture that has a cord coming off the right side of the big disk and a cord coming off the left side of the small disk. I know the assembly spins clockwise because the mass on the big cylinder has more torque than the one on the small cylinder.

Part B I'm not so sure about. Basically I equated the tension in the wire to the tangental force from the pulley, and wrote the torque equation: [itex] \tau = R F [/itex]. From there I went to [itex] R F = I\alpha = \frac{1}{2} mR^2\alpha [/itex] and solved for [itex] \alpha [/itex]. The final result was [itex] \alpha = \frac{2F}{mR} [/itex]. My only question is did I do it right and if not what other factors do I need to include?

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# Homework Help: Acceleration/Rotational KE

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