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Homework Help: To set a swing going

  1. May 24, 2010 #1
    Is it impossible for me to to set a swing (on which a child weighing 66 pound is sitting) going, so that its velocity from the very beginning is 33 ft/s? Why/Why not?

    I find myself quite lost with this question so I have no attempts at any solutions...all i know is that it sounds impossible to me..but i don't know how to prove it:S Maybe one could in some way use momentum p=m*v ...

    Would really appreciate some help!:)
     
  2. jcsd
  3. May 24, 2010 #2

    tiny-tim

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    Welcome to PF!

    Hi lisa1234! Welcome to PF! :smile:
    Well, suppose the child, instead of being stationary on a swing, was stationary on the ground (say, on ice) …

    could you then set the child moving at 33 ft/s ?
     
  4. May 24, 2010 #3
    No probably not...i mean it's almost impossible to even run that fast..
    But aren't there any equations i can use to prove it??
     
  5. May 24, 2010 #4
    Well, try calculating the acceleration that would be needed to set anyone moving with any velocity in no time assuming that the velocity in the beginning was 0 :P. This advice is not as stupid as it seems to be ;)
     
  6. May 24, 2010 #5

    tiny-tim

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    What would happen if another child collided with it?
     
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