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Homework Help: Helpy me quick question

  1. Jan 3, 2010 #1
    1. The problem statement, all variables and given/known data

    As a meteor moves from a distance of 16 earth radii to a distance of 2 eath radii from the center of earth, the magnitude of the gravitational force between the meteor and earth becomes

    1) 1/8 as great
    2) 8 times as great
    3) 64 times as great
    4) 4 times as great

    2. Relevant equations

    i think theres an equation to it but i dont know

    3. The attempt at a solution

    i know that double the radius is 4 times the force but im not sure how to answer this question
     
  2. jcsd
  3. Jan 3, 2010 #2

    Dick

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    The equation you want is called 'Newton's law of universal gravitation'. It's really pretty famous. Can you try and find it?
     
  4. Jan 3, 2010 #3
    oh is choice 3 correct?
     
  5. Jan 3, 2010 #4

    Dick

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    I would feel better answering that if you explain why you think so.
     
  6. Jan 3, 2010 #5
    emm i did 16 square divided by 2 square and got 64
     
  7. Jan 3, 2010 #6

    Dick

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    That's good. It's right.
     
  8. Jan 3, 2010 #7
    oh thx for the help
     
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