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Homework Help: Rotational Velocity Question - I think?

  1. Apr 15, 2008 #1
    It has been said that a parade of Chinese twenty a breast could march forever past an observing point. If we assume the parade to march at 3 miles per hour, with ranks 4 feet apart, what is the Chinese birth rate, in babies per hour?

    ok, so far I've drawn a picture, and converted all my information, and if I'm correct, I need to use this formula: a= v^2/r
    but if its a centripetal acceleration problem then where does the birth rate come into play? I'm so confused...

    4mph = 1.34m/sec
    4 ft = 1.22m
    r= 20 people
    d= 40 people
    v= 1.34 m/sec

    a= 1.34^2/20?
    & babies per hr. = frequency
  2. jcsd
  3. Apr 15, 2008 #2
    sorry, the title is wrong. =[
  4. Apr 15, 2008 #3


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    If you've figured out that the title is wrong, I hope you've also figured out that v^2/r has nothing to do with the problem.
  5. Apr 17, 2008 #4
    circles have nothing to do with this, in the time taken for 1 row of people to go past the observation point, 20 more babies need to be born, little problem that babies can't walk (so it may be you have to take into account a birth rate from a few years ago, so you can work on number of new walking chinese people) sounds a bit pointless to me
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