(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A puck of mass m = 1.10 kg slides in a circle of radius r = 18.0 cm on a frictionless table while attached to a hanging cylinder of mass M = 3.00 kg by a cord through a hole in the table. What speed (in m/s) keeps the cylinder at rest?

2. Relevant equations

F = ma

3. The attempt at a solution

I know the F_{net,y}for the hanging cylinder is zero because it does not move, so I deduced that T - F_{g}= 0.

On the puck the 2 things I looked at was the a moving towards the hole and the tension which I am also deducing is moving towards the hole, away from the puck. (Note: I left out F_{N}and F_{g}because I didn't see how they would apply in the equation for the puck.) I thus got the equation T = ma.

I then plugged in the in this T into the previous equation to get: ma - F_{g}= 0

I then simplified the equation to a = g. Knowing that a in circular motion with constant velocity is a = v^{2}/R, so the eqation I ended up with was v = √Rg. This came out to 1.328 ms^{-1}, which is wrong. Could somebody tell me where my thinking went astray and how I can fix this.

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# Homework Help: Centrifugal Force of a puck

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