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Homework Help: Rope, Pulleys. and Lots of Tension

  1. Sep 27, 2004 #1
    Rope, Pulleys....... and Lots of Tension!!!!!!!!


    For the following problem a picture is really needed so I tried drawing one on Paint and uploading a bitmap file ut it said that it was too large........

    A 7 kg monkey climbs up a massless rope that runs over a frictionless tree limb and back down to a 20 kg package on the ground.

    (a) What is the magnitude of the least acceleration the monkey must have in order to lift the package off the ground?

    Assume that after the package has been lifted, the monkey stops its climb and holds onto the rope.
    (b) What is the monkey's acceleration?

    (c) What is the tension in the rope?

    What I did was use the Equation Force = Mass * acceleration.

    Using tension as the force the equation for the monkeys side became

    Tension= Mass*(acceleration of gravity + acceleration of monkey)

    My answer for (a) was 18.2 m/s^2
    (b) was 3.43 m/s^2
    (c) I couldn't answer it.........

    Please help me............. I have spent already 4 hours on this single problem already.

  2. jcsd
  3. Sep 27, 2004 #2

    Doc Al

    User Avatar

    Staff: Mentor

    How did you get this?
    If you know the monkey's acceleration, then you should be able to find the tension in the rope that will produce that acceleration.
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