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Homework Help: Breaking Tension

  1. Oct 5, 2004 #1
    I am brand new to this website so I hope somebody can help. I have a homework problem that goes like this: A girl of mass M is taking a picnic lunch to her grandmother. She ties a rope of length R to a tree branch over a creek and starts to swing from rest at a point that is a distance R/2 lower that the branch. What is the minimum breaking tension for the rope if it is not to break and drop the girl into the creek?
    I do not even know where to begin in this problem. My text book does not mention minimum breaking tension at all. If anybody knows a formula to use I would really appreciate it. Thanks. :confused:
  2. jcsd
  3. Oct 6, 2004 #2


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    What would be the tension on the rope at the bottom of her swing?
  4. Oct 6, 2004 #3


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    With "minimum breaking tension" is meant that value of the tension which will cause the rope to break (ideal rope dynamics becomes invalid when that happens).
    Clearly then, in a problem where the tension might be varying, it is crucial that the "minimum breaking tension" is larger than the maximal tension you may compute from your problem (in which you assume that the rope does NOT break).
    Follow Tide's instruction.
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