A ball of mass m is spun in a vertical circle having radius R. The ball has a speed v(o) at its highest point. Take zero potential energy at the lowest point, and use the angle theta measured with respect to the vertical.(adsbygoogle = window.adsbygoogle || []).push({});

(a) Derive an expression for the speed v at any time as a function of R, theta, v(o), and g.

(b) What minimum speed v(o) is required to keep the ball moving in a circle?

I found part (a) to be:

v = *square root*[ v(o)^2 + 2gRsin(theta) ]

I'm not totally sure if this is correct, and i don't know how to find the minimum value of v(o).

Is someone able to help?

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# Homework Help: Circular Motion, and Conservation of Energy problem

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