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Homework Help: Climbing a rope

  1. Aug 4, 2006 #1
    If a man, weighing m1g is tryingting to climb up or down a rope, and the max tension T that the rope can withstand is 2m1g/3, then find the maximum speed and acceleration with which the man can climb without breaking the rope.

    My work:
    2m1g-m1g=m1a
    =>a=-1g/3

    doesn't this mean that the rope will break?
     
  2. jcsd
  3. Aug 4, 2006 #2

    Chi Meson

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    Apparrantly the man can not climb this rope. If he weighs w, and the rope can only hold (2/3)w, he can not even hang on to the rope, nevermind climbing it.

    He can, however, slide down the rope at a constant acceleration of (1/3)w

    BTW, "find the maximum speed" is nonsense for this problem unless the length of the rope is given.
     
  4. Aug 4, 2006 #3

    HallsofIvy

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    He can climb down the rope just by letting go- no tension at all!

    As Chi Meson said, if the rope can only support 2/3 of the man's weight, he cannot climb up at all- he can't even hang on.
     
  5. Aug 6, 2006 #4
    thank you very much!
     
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