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Homework Help: Kinematics Spinning Disk

  1. Oct 25, 2007 #1
    Problem 13.30
    A thin, 60.0g disk with a diameter of 7.00 cm rotates about an axis through its center with 0.240 J of kinetic energy. What is the speed of a point on the rim?

    2. Relevant equations
    m=.06kg
    r=.035m
    KE=.240J

    3. The attempt at a solution

    K=(1/2)*I*(w^2)
    I=(1/2)*M*R^2

    I'm using the formula above but I'm not getting the right answer. My numbers seem way to small. I eventually get w(omega) alone. Where do I go from here. Do i need to solve for the length to figure out rad/s then convert to m/s?

    Perhaps I am approaching this wrong.
     
  2. jcsd
  3. Oct 25, 2007 #2
    Calculation error, sorry. Mods you can delete.
     
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