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Distribution of mass and angular momentum

  1. Oct 18, 2012 #1
    If I had two cylinders of equal weight and size, but cylinder one had the weight distributed around an outer radius and cylinder two had it distributed around an inner one, would it change their angular momentum going down an incline? Would they be equal, or would cylinder two have greater momentum? And how would I reflect this when solving for L?
     
  2. jcsd
  3. Oct 18, 2012 #2

    haruspex

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    The moment of inertia of a body is calculated by integrating dm r2, where dm is an element of mass and r is its distance from the axis of rotation. Thus, when mass is close to the axis (your cylinder two), the MI is less, so for a given rotation rate the angular momentum is less.
    To calculate it you will need to know the actual mass distribution.
     
  4. Oct 18, 2012 #3
    Thanks!

    For the problem itself, I will have numbers for the mass, which is distributed equally around the center of the cylinder, so will be able to calculate the actual momentum.
     
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