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Homework Help: Tension from string upon a rock

  1. Feb 18, 2009 #1
    1. The problem statement, all variables and given/known data
    Two 3 kg masses are attached to a string at r1=.5m and r2=1.5m from where the string is held in your hand. You swing them around together at 2 revolutions per second, each of them. The tension holding mass 2 (the distant part of the string) is what fraction of the tension near your hand?

    2. Relevant equations

    No Idea.

    3. The attempt at a solution
    No idea how to figure this problem out.
  2. jcsd
  3. Feb 18, 2009 #2


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    Homework Helper

    Welcome to PF.

    Are the blocks tied together in some way?

    Like head to tail?
  4. Feb 18, 2009 #3

    That is all the information I received on the question.
    A hint that was given was:[Hint: you can work in proportions without having to numerically solve for either of the centripetal forces required on the two masses]
  5. Feb 18, 2009 #4


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    Homework Helper

    I read it more carefully. Apparently it is tied to the same string at each of the 2 radii.

    What is the force of a single mass at some radius rotating in a circle?
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