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Homework Help: Simple Gravitational Question

  1. Sep 26, 2010 #1
    I've done a bunch of these before, but dunno why I'm not getting the right answer this time around:

    A space telescope of mass m[t]=10,000 kg is in a stable circular orbit above the Earth at an altitude h=3630 km. The radius and mass of the earth are R[e]=6370 and M[e]=6x10^24 kg. Newtons gravitational constant is 6.672x10^-11.

    What is the acceleration of the space telescope as it orbits the earth?


    So this is simple enough-we're looking for the centripetal acceleration. So m[t]*Ac=GM[e]m[t]/R^2[earth center to satellite]. The m[t]'s cancel out, so we have centripetal acceleration =GM[e]/R^2, and I'm getting a really large number, even though the answer is supposed to be 4.0 m/s^2. What do you see I'm doing wrong?
  2. jcsd
  3. Sep 26, 2010 #2


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    R[e] is in km, did you convert it meters?
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