If I wanted to prove that whilst spinning a ball attached by a string in a circle, that:(adsbygoogle = window.adsbygoogle || []).push({});

F = 4 * pi^2 * r / T^2

Where F = force from tension

r = radius

T = period of one rotation

Ie. Proving that:

F is directly proportional to r

F is directly proportional to m

F is direction proportional to T^-2

How would I measure the force on the string? This is just school physics, so I can't do anything fancy. It'll probably just be someone spinning it in circles above them. The other variables are easy enough, but I need to be able to compare them to force. The only thing I thought of was using the formula F=ma, but the problem is the acceleration is constantly changing so can't be measured.

Thanks

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# Homework Help: Circular Motion

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