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

In space in the absence of gravity, there is a post of "infinite mass," meaning that the post is fixed or "nailed down" and cannot move. A ball of massm_{1}is connected to the post by a cable of negligible mass of lengthL_{1}. A second ball of massm_{2}is connected to the first ball by a second cable of negligible mass of lengthL_{2}. The entire contraption (except for the post) is moving around the post in a perfect circle with a constant angular speed ω^{2}(in radians per unit time). Find the tension in each cable.

2. Relevant equations

F = ma= mv^{2}/r = mω^{2}r

3. The attempt at a solution

So there is a cable tension (T_{1}) acting on the ball with mass m_{1}and then a cable tension (T_{2}) acting on the ball with mass m_{2}.

This is what I have, and I'm wondering if it is correct. There is no movement or force in the y-direction at all, so I think only the x-components matter...but if I include cosθ, then there's a denominator of zero, so I'm guess that's not supposed to be there. Are these correct then?

For cable of length L_{1}, T=m_{1}ω^{2}L_{1}

For cable of length L_{2}, T=m_{2}ω^{2}(L_{1}+L_{2})

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# Homework Help: Uniform circular motion; two balls, two cables, and a post; no gravity

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