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Homework Help: Escape Velocity (from surface of the Earth)

  1. Apr 13, 2010 #1
    1. The problem statement, all variables and given/known data

    A satellite with a mass of 5.00x10^2 kg is in a circular orbit, whose radius is 2re, around Earth. Then it is moved to a circular orbit with a radius of 3re.

    e) Calculate the escape velocity for the satellite if it is on Earths surface.

    2. Relevant equations

    Vesc = Sq.root of 2GMp/r

    3. The attempt at a solution

    Vesc = Sq.root of 2(6.67x10^-11)(5.98x10^24)/6.38x10^6

    Vesc = Sq.root of 125036363.6
    Vesc = 11182.966 m/s
    Therefore the velocity of the satellite must be > 11182.966 m/s

    I must of done something wrong because 11000m/s seems way to fast! Plz help.
    Thanks in advance.
  2. jcsd
  3. Apr 14, 2010 #2


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    Homework Helper

    I think that the escape velocity of the Earth in the km/s range. So that should be correct.
  4. Apr 14, 2010 #3
    Use google to check ;] your answer is correct
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