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Homework Help: How would I solve this problem (center of mass)?

  1. Nov 27, 2007 #1
    Three balls with masses of 5 g, 1 g, and 7 g,
    respectively, are connected by massless rods.
    The balls are located (in meter intervals) as
    in the figure.

    Imagine the first quadrant of a graph.
    The 5 gram is at point (3,8)
    The 7 gram is at point (5,2)
    The 1 gram is at point (9,6)

    What do do to find the center of gravity? I've looked online and I only see formulas for 2 objects instead of 3 so I'm stuck. Forgot to say they are all connected by massless rods.
    Last edited: Nov 27, 2007
  2. jcsd
  3. Nov 27, 2007 #2
    the sum of the equations...
  4. Nov 27, 2007 #3
    Sum of what equations?
  5. Nov 27, 2007 #4
    the sum of the center mass equation... and you gotta break it down into y and x... there is an similar example online, i'll look it up for you
  6. Nov 27, 2007 #5
  7. Nov 27, 2007 #6
    Thanks so much! Would the answer be:

    In the X direction
    ((5x3) + (7x5) + (1x9))/13=4.54

    In the Y direction
    ((5x8) + (7x2) + (1x6))/13=4.6
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