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Homework Help: Rotating Space Station

  1. Dec 4, 2011 #1
    The problem statement, all variables and given/known data
    A proposed space station includes living quarters in a circular ring 62.0 m in diameter. At what angular speed should the ring rotate so the occupants feel that they have the same weight as they do on Earth?

    The attempt at a solution

    I assumed that to do this problem, Fcp had to equal the force of gravity.

    Fcp = Fg

    mv^2 / r = mg
    v^2 / r = g
    v = √(rg)
    v = √(62g)
    v = 24.65

    v = ωr
    ω = v/r
    ω = 24.65 / 62
    ω = 0.398 rad/s

    This isn't correct.

    Does anyone have any advice on what to do differently? Any help would be greatly appreciated.
  2. jcsd
  3. Dec 4, 2011 #2


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    I don't see anything wrong with your physics. The problem may lie with your math. What value of g did you use? Using g = 9.81 N/kg, I get v = 24.66 m/s (to two decimal places).
  4. Dec 4, 2011 #3
    I tried both, but when whittled down to the required three sigfigs, the answer is still 0.398 rad/s.

    I'm at a loss as to what to do differently.
  5. Dec 4, 2011 #4


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    Oh. :redface:

    62.0 m is the diameter of the space station, not its radius.

    It helps if you read the problem carefully (and I apply this advice to you and me both!).
  6. Dec 4, 2011 #5
    :redface: Do you ever have one of those moments where you just can't believe you mixed up something really simple?

    Thank you very much for pointing that out. I feel a bit foolish, but I do have the right answer now.
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