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Center of mass equation help

  1. Jul 8, 2013 #1
    so for the center of mass of an object..

    x = (m1x1 + m2x2 + ...) / M total
    y = (m1y1 + m2y2 + ...) / M total

    how come in this equation the denominator is the total mass of the system? It seems like it would make more sense to have the denominator the total mass in whatever component you are trying to figure out...

    i feel like it should be
    x = (m1x1 + m2x2 + ...) / Mx total

    and though i realize this is wrong i was hoping somebody could see what i think i see and explain where my thinking is wrong.
  2. jcsd
  3. Jul 8, 2013 #2
    Simply put, it's a weighted average.
    Last edited: Jul 8, 2013
  4. Jul 8, 2013 #3


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    Mass is also not a vector quantity (it has no components like a force, for instance).
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