A small ring of mass M can move freely on a smooth, circular hoop, of radius R. A couple of light inextensible strings that pass over smooth pegs situated below the center of the hoop at the same horinzontal level are attached to the ring. Their other ends are attached to particles of mass m.(adsbygoogle = window.adsbygoogle || []).push({});

Given that the ring is below the pegs and that M > m sin(x/2), the distance between the pegs is 2 R sinx, and that the hoop is fixed in a vertical plane, prove that the system has three positions of equilibrium.

I'm having a very hard time setting up the potential energy equations -- I always end up with too many variables and constants. Can anyone help?

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# Homework Help: Potential energy equations

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