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Homework Help: Applying Newton's laws

  1. Nov 2, 2008 #1
    1. The problem statement, all variables and given/known data

    A 8 kg monkey climbs up a massless rope that runs over a frictionless tree limb and back down to a 15 kg package on 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?

    2. Relevant equations


    3. The attempt at a solution

    The first question was to find the minimum acceleration the monkey must have to lift the crate. I got a=8.575 m/s^2.

    If the monkey stops climbing I believe it no longer has the acceleration of 8.575 so the only forces acting on it are gravity and the rope. Because the monkey is 8kg and the crate is 15kg i believe the crate would then begin to fall simultaneously raising the monkey due to its weight being greater than the monkey's. The weight of the monkey is 78.4N. subtract that from the weight of the crate gives 147N-78.4N and i get 68.6N which should be the net force. I then divided the net force by the mass of system of 23kg to get a=2.98.

    Im pretty sure this is incorrect. Any hints in the right direction or indication of my error(s) would be greatly appreciated as always :)
  2. jcsd
  3. Nov 2, 2008 #2
    Yet again my issue was with the website not my work :/

    I got it
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