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Homework Help: Did I do this correctly?

  1. Mar 28, 2005 #1
    Calculate the force of gravity on a 1-kg mass if it were 6.4 x 10^6 m above Earth's surface (twice Earth's radius).

    Known: Mass of object 1 = 1 kg
    Mass of Earth = 6 x 10^24 kg
    Earth's radius = 6.4 x 10^6 m; 2x this is 1.28 x 10^7 m
    G = 6.67 x 10^-11 N*m^2/kg^2

    Equation: F = G(Mass of object)(Mass of Earth)/(Distance)^2
    = (6.67 x 10^-11 N*m^2/kg^2)(1 kg)(6 x 10^24 kg)/(1.28 x10 ^7 m)^2
    = 2.4 N
     
  2. jcsd
  3. Mar 28, 2005 #2
    yes you did it right

    it's simply asking you for hte attraction force between the object and earth, really.
     
  4. Mar 28, 2005 #3
    Ok, thank you for checking.
     
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