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

There is a string of length L dropped through a spool of thread. 10 paper clips are tied to each end and one end is twirled so that one bunch of clips moves in a horizontal circle at speed v while the other hangs vertically. Neglecting friction, write an expression:

a) for the distance d as a function of v and L, where L = r + d (r = radius)

b) for g in terms of v and r, the radius of the circle.

2. Relevant equations

a(c) = v^2 / r

3. The attempt at a solution

I don't even know where to begin. Since L is already given, d is obviously L - r. I've tried to re-arrange the centripetal acceleration equation to get r = v^2 / a, but that still introduces a. I then took the regular velocity v = 2pi*r / t but rearranging that for r will still give v*t. What am I missing?

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# Homework Help: Expressing centripetal action with variables

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