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Homework Help: Angular momentum

  1. Nov 14, 2006 #1


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    Somewhat confused about this problem and need some clarification:

    Problem: A particle of mass 0.01kg rotates with angular speed of 2 rad/s in a circle of radius 0.8m. What is its angular momentum?

    I think the answer should be:
    I = 0.01kg X (0.8m^2) = 0.0064 kg/m^2.
    w = 2 rad/s.
    Therefore, angular momentum = 0.0064 kg/m^2 X 2 rad/s = 0.128 kg*rad/m^2*s.

    Am I on the correct path?
  2. jcsd
  3. Nov 14, 2006 #2
    You are correct in your calculations, but not in your units. The unit for rotational inertia is kg*m^2, which is what your math would indicate. Also, the radians are generally not included in the units for angular momentum, so you should come up with an answer in the form kg*m^2/s.
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