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Homework Help: Dynamics question

  1. Apr 30, 2009 #1


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    1. The problem statement, all variables and given/known data

    Two weights are connected by a very light flexible cord that passes over a 50 N frictionless pulley of radius .300 m. Pulley is a solid uniform disk and is supported by a hook connected to a ceiling. What force does the ceiling exert on the hook? There are two weights around each side of the disk, one is 75 N and the other is 125 N. Answer is 249 N.

    2. Relevant equations
    I = 1/2 MR^2

    3. The attempt at a solution
  2. jcsd
  3. May 2, 2009 #2
    As in any dynamics problems, start by drawing out your free body diagrams for each body - your two weights and the pulley, taking into acount all the forces acting on the weight, and the sources of torque for the pulley.

    Then you can apply F = ma to each body, for each axis of movement, but don't forget your appropriate constraints.
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