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Homework Help: String doubt

  1. Oct 6, 2007 #1
    When does a bob attached to a string become slack???When mgcos@ = mv^2/r?
  2. jcsd
  3. Oct 6, 2007 #2


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    When doing what? You're going to have to provide a bit more information about what the bob on the string is doing?
  4. Oct 6, 2007 #3


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    It depends if you are restricting the angle to be below 90 degrees or if you may go above.
    The equation (for theta smaller or equal to 90 degrees) is

    T - mg cos theta = m v^2/R

    The rope becomes slack if T=0.

    what can you say about theta and v in that case?
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