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Gravitation + forces

  1. Oct 10, 2009 #1
    1. The problem statement, all variables and given/known data

    1.A satellites are placed in a circular orbit that is 1.43 × 10^8 m above the surface of the earth. What is the magnitude of the acceleration due to gravity at this distance

    2. Relevant equations

    1.I used G*mE/r^2

    3. The attempt at a solution

    1. Got an answer of .0195m/s^2 I think I get this and have no idea why it is wrong.
    Last edited: Oct 10, 2009
  2. jcsd
  3. Oct 10, 2009 #2

    Doc Al

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    Staff: Mentor

    What values did you use for G, mE, and r?
  4. Oct 10, 2009 #3
    Is the satellite [tex]1.43\cdot 10^8 m[/tex] above the surface of the earth, or [tex]1.43\cdot 108 m[/tex] above the surface of the earth?

    Using the former, I got a result only slightly different from yours. Remember that the [tex]r[/tex] in that formula is the distance between the center of the earth and the satellite, not from the surface of the earth and the satellite.
  5. Oct 10, 2009 #4
    O thax I didn't realize it was saying above the surface. I meant 1.43x10^8. :)

    using 6.674E-11 for G

    Mof earth= 5.98E24


    I get an answer of .0179, does that check out?
    Last edited: Oct 10, 2009
  6. Oct 10, 2009 #5
    Got it thax
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