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Homework Help: Newton's law story problem

  1. Jul 6, 2008 #1
    One day a girl jogging in the park, doesnt see a sign up ahead, hits it and falls to the ground.

    Which of Newton's 3 laws is involved in this story?

    I think that newton's 1st and 3rd law are invovled, not sure about the 2nd.
     
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  3. Jul 6, 2008 #2

    Hootenanny

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    I agree that both the first and thrid laws are involved, however for the second, does the girl's velocity change as she hits the sign?
     
  4. Jul 6, 2008 #3
    Yes, because she does fall to the ground so her velocity becomes zero?
     
  5. Jul 6, 2008 #4

    Hootenanny

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    Well yes, but the point I was trying to make is that she undergoes an acceleration and so Newton's 2nd law is also involved.
     
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