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A childish question, even though I'm an aligator

  1. Jun 16, 2006 #1
    Alright, so I was just thinking the other day about say...a bowling ball in the center of the Earth, where the center of the Earth is sectioned off by a perfect cubic room. Now say the bowling ball was positioned in the center of that room. I was wondering where the bowling ball would fall towards. Would it just float there? Please neglect all the reasons why this experiment would be nearly impossible to perform. Just imagine...

    Thank You.
  2. jcsd
  3. Jun 16, 2006 #2
    my guess is yes
  4. Jun 16, 2006 #3


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    The centre of the Earth will actually be a slightly oblate sphere, not a cube. In any event, gravity is equal in all directions, so the ball will just hover.
  5. Jun 17, 2006 #4
    Even better than this, if the ball were to be displaced just slightly from the center it would oscillate about the center point. In other words, the (hollowed) center of a gravitating body is a stable equilibrium point.
  6. Jun 17, 2006 #5


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    As Danger points out, the gravitational forces inside a hollow sphere cancel out - no matter where inside the sphere you put the bowling ball, it will remain there.
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