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Inertia, Gravitational Potential Energy

  1. Apr 22, 2008 #1
    1. The problem statement, all variables and given/known data
    A meter stick with a mass of .160kg is pivoted about one end so it can rotate without friction about a horizontal axis. The meter stick is held in a horizontal position and released. As it swings through the vertical, calculate (a) the change in gravitational potential energy that has occured; (b) the angular speed of the stick; (c) the linear speed of the end of the stick opposite the axis. (d) Compare the answer in part (c) to the speed of a particle that has fallen 1.m, starting from rest.

    3. The attempt at a solution

    i have no idea, i cant even get the first part. i beleive it is supposed to be something kind of like this sitting on a table: 445.jpg
    and then they drop it while it is spinning?
    idk i could use some help
  2. jcsd
  3. Apr 22, 2008 #2


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    HINT: To calculate the the change in G.P.E you can treat the meter stick as a point particle of mass 0.16kg located at the centre of mass of the meter stick.
  4. Apr 22, 2008 #3
    What I'm reading is if you held a meter stick in your hand parallel to the ground and then let it rotate down from the end you're holding so the opposite end falls while you still hold the end that was in your hand. That's rotating about one end of the meter stick.

    Do correct me if I'm wrong.
  5. Apr 23, 2008 #4
    @ above:
    100 percent perfect interpretation.

    The rod is in perfect rotation.
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