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Energy can't create or destroy

  1. Dec 28, 2003 #1
    ccording to energy of conservation, energy can't create or destroy.
    So, where does the Gravity in earth come from??
  2. jcsd
  3. Dec 28, 2003 #2


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    Staff Emeritus
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    Gravity is not energy, gravity is force (and there is no "conservation of force law"). The POTENTIAL ENERGY due to the force of gravity on an object depends upon the position of the object and is "created" by the work done to put the object in that position.
  4. Dec 28, 2003 #3
    On the other hand, a bit philosophical though, gravity only exists if a body has gravitational potential energy. What's your comment on that?

    The question might look simple, but too me it isn't.
  5. Dec 28, 2003 #4


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    [?] [?] It really is simple. Potential energy is just that - potential energy. You can convert it to kinetic energy and back, but you don't ever get anything for free. It does not violate conservation.

    However, if you are asking where the initial gravitational potential energy of the universe came from - that's the big bang. Where did the BB come from? Now you're into philosophy.
    Last edited: Dec 28, 2003
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