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Central force

  1. Oct 27, 2008 #1
    What exactly is the "center of force"?

    For instance, you use reduced mass to make an orbital problem one body. Is the center of force the r "seperation between the bodies"? Or is the center of force at the center of mass? In an ellipse, the center of mass is always at one of the foci, right?
  2. jcsd
  3. Oct 27, 2008 #2


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    When dealing with gravity, a spherically symmetric object can be treated as if the entire mass was at the center of mass, so r in the force of gravity equation is measured from the center of mass.

    Your statement about the ellipse is correct.
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