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Point particles

  1. Aug 26, 2008 #1
    I have a homework question that is referring to a pivot rod with unequal masses.

    The spheres are small enough that they can be considered point particles.

    what exactly does this mean?

    I know how to solve the equation, but I'm assuming I can't use the I=2/5mr^2 to solve it.
    If the masses are negligable, why are they unequal to begin with? LOL
  2. jcsd
  3. Aug 26, 2008 #2

    Doc Al

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    Staff: Mentor

    It means that you can ignore the sizes of the spheres, not their masses. (They have no rotational inertia about their center of mass.)
  4. Aug 26, 2008 #3
    nvm, I just used what they were asking me to use, I just assumed the program knew that m_1 was lighter than m_2 and I was assuming correctly.
  5. Aug 26, 2008 #4
    Thanks Doc Al!
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