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Gravitational force, is it inverse square law?

  1. Dec 1, 2009 #1
    I may be having a misconecption, please guide me.

    The force of gravitation between two masses is inverse square law force as depicted by the formula F=G*m1*m2/r'2. Doesn't it mean that this force is one quarter of the origional when the distance between the masses is doubled. Now if a body of mass m is on Earth at a certain distance 'r'. At distance '2*r' the force should be divided by four. But in real the force (weight of the mass m) remains pretty same and does not change in the predicted proportion. What is wrong with my interpretation here?
  2. jcsd
  3. Dec 1, 2009 #2


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    You are measuring from the surface. But the mass attracting you is not at the surface. Where is it?
  4. Dec 1, 2009 #3

    Its the centre of earth.
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