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Universal Gravitation Law Q.

  1. Jan 28, 2010 #1
    Hello all,

    1) Does the universal gravitation law apply to every two particles in the universe, no matter how far they are from each other?

    For instance, is there a gravitation force between the pen in my hand and the farthest particle(or star) in the universe, I don't care how small this force is, but I am asking about its existence.

    2) Is this law what makes the atoms of a solid material stick together, and makes it rigid?

    Thanks a lot
  2. jcsd
  3. Jan 28, 2010 #2


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    Welcome to PF!

    Hello Mohammad! Welcome to PF! :smile:
    Yup! :biggrin:
    No, that is done by the electromagnetic force, between the electrons of the different molecules. :wink:
  4. Jan 29, 2010 #3
    Hello Mohammad! I am new here too!
    well for this part of the question the answer is, just like tiny-tim said, Yes. Since the quantitative equation is

    Your pen in your hand has mass so does the distant star. Hence there is force existing but the thing is it is very very very small.
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