A ball of mass m attached to a string of length L moves in a circle in a uniform vertical plane. When the ball is at the top of its path, the tension in the string is equal to its weight. Assume that air resistance is negligible.(adsbygoogle = window.adsbygoogle || []).push({});

1. Total force of the ball at the top in terms of m, L, and g:

Okay, total force in a circular motion diagram is:

Centripetal Force= mv^2/r

Centripetal Force=mg+tension

Since tension is the same as weight on the top of the circle, then:

Centripetal Force=mg+mg=2mg

is this the correct way of thinking?

2. speed at the ball at the top?

2mg=mv^2/r

v=2gr

correct?

3. speed at the bottom?

it would be the same as on the top right?

4. Tension at the bottom:

T=mg correct?

5. Speed of the ball when the string is horizonal:

It would be the same correct?

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# Homework Help: Circular motion

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