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Vertical circle motion

  1. Sep 29, 2011 #1
    1. The problem statement, all variables and given/known data
    A ball of mass m is suspended from a rope of length R. The ball is set into freely swinging circular motion a vertical plane. The centripetal acceleration of the ball at the top of the circle is 13g. What is the centripetal acceleration of the ball at the bottom of the circle.

    2. Relevant equations

    3. The attempt at a solution

    At the top,

    T + mg = mv^2/R

    At the bottom, T - mg = mv^2/R

    My question is does Ttop and Tbtm the same?

    Hint for this question?
  2. jcsd
  3. Sep 29, 2011 #2
    Using conservation of energy principle helps you get v(top) in terms of v(bottom) and you may deduce whether the tensions are equal.
  4. Sep 29, 2011 #3
    Ui + Ki = Uf + Kf

    0 + 0.5mVbtm^2 = 2mgR + 0.5mVtop^2

  5. Sep 29, 2011 #4
    Yes. Continue.
  6. Sep 29, 2011 #5
    I got 17g!
  7. Sep 29, 2011 #6
    Now you know what the answer to your question.
  8. Sep 29, 2011 #7
    Yes! thank you.!
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