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Homework Help: Gravitational Force question

  1. Apr 10, 2008 #1
    1. The problem statement, all variables and given/known data
    What is the force of gravity acting on a 4500kg satellite when it orbits three Earth radii from the Earth's center?

    2. Relevant equations
    Gm1m2/r²
    mass of the earth=5.98*10^24kg
    radius of the earth=6370km

    3. The attempt at a solution
    This is a multiple choice question, with answers:
    15000N
    45000N
    500N
    1500N
    5000N

    However, what I get from plugging in is:
    [(6.67*10^-11)(4500)(5.98*10^24)]/(3*6370)²
    which equals roughly: 5.0*10^9 which is completely off any of the answers... can anyone help me?

    hahaha, never mind! I forgot to convert the km to m... -_-
     
    Last edited: Apr 11, 2008
  2. jcsd
  3. Apr 11, 2008 #2
    You're not using SI units for distance.
     
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