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Gravitational energy

  1. Jul 15, 2011 #1
    When I multiplied angular accelaration with surface area of sphere .I got an equation for energy.

    What do this equation mean by?
    Is this equation describe gravitational energy?
  2. jcsd
  3. Jul 16, 2011 #2


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    Can you post the equations you used and the problem they were used in?
  4. Jul 16, 2011 #3
    But dimensionally this equation is correct.
  5. Jul 16, 2011 #4
    Angular accelaration*surface area of a sphere = Energy
    Angular velocity/time*4(pi)r2=Energy

    Dimensional formula:-
    M0 L0 T-2 * M L2 T0 = M L2 T-2

    M L2 T-2 = Energy

    I take this energy equation in terms of planetry motion .
    Last edited: Jul 16, 2011
  6. Jul 16, 2011 #5

    Vanadium 50

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    The fact that something has dimensions of energy doesn't make it an energy. Torque, for example.
  7. Jul 16, 2011 #6


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    First, if its truly surface area, you get M0 not M. The whole equation is massless.
    The way you have written it, it is the mass of a thin spherical shell times the angular acceleration.

    Second, Work also has the dimensions of Energy. I think your equation gives you the amount of work expended to accelerate (spin up or spin down) the thin spherical shell by that much.
    Jim Graber
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