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Does a rock have energy?

  1. Jun 7, 2007 #1
    Since a rock has gravity, doesn't a rock have energy within it? Are there bonds caused by energy at the atomic level within a rock?
     
  2. jcsd
  3. Jun 7, 2007 #2

    G01

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    A rock has energy in several ways. Assuming it's sitting still, a rock may have gravitational potential energy because of gravity pulling on it. It has energy stored in the chemical bonds in the molecules of the rock. Also, if the rock has some charge on it(its a possibility), it could have electrical potential energy if it was in an electric field. Then of course there is the rest energy of the rock. According to relativity(E=mc^2), the rock has some energy just by being massive.

    So, yes! The rock has energy stored in many different ways.
     
  4. Jun 7, 2007 #3
    Thank you.
     
  5. Jun 7, 2007 #4
    It has no sense in saying that a rock has gravity...

    Because of gravitational attraction between the earth and the rock, the rock-earth system has a potential energy. The work done is achieving this potential energy is the negative of the potential energy.

    The matter of potential energy is merely a definition, you won't find the "energy" as a perceivable quantity but physicists define the rock-earth system as having potential energy in the sense that work done can be achieved through the utilization of this energy..

    And as for the "bonds cause by energy at the atomic level within a rock" , if you are still refering to the gravitation attraction or the potential energy of the rock-earth system, it has absolutely nothing to do with gravity or "the gravity the rock has". Gravitational force is better explained in terms of space-time geometry rather than "bonds at the atomic level" , which I wont delve into here..

    Actually, I dont really understand your question at all, or that you had been seriouly misconceived by what you say as "Since a rock has gravity" ...

    Correct me if I am wrong anyone.. :D
     
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