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Homework Help: Bungee jump

  1. Feb 28, 2008 #1
    1. The problem statement, all variables and given/known data

    Chris jumps off a bridge with a bungee cord tied around his ankle. He falls for 15m before the bungee cord begins to stretch. Chris's mass is 75kg and we assume the cord obeys Hooke's law F = -kx, with k=50N/m. If we neglect air resistance estimate how far below the bridge Chris's foor will be before coming to a stop. Ignore the mass of the cord and treat Chris as a particle.


    2. Relevant equations
    well i know h = 60m. but i don't know how im suppose to get there.


    3. The attempt at a solution

    no idea what so ever
     
  2. jcsd
  3. Feb 29, 2008 #2
    pleae someone help
     
  4. Feb 29, 2008 #3

    Doc Al

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    Staff: Mentor

    Use conservation of energy.
     
  5. Mar 3, 2008 #4
    how exactly do i encorporate hookes law in the conservation of energy equation?
     
  6. Mar 4, 2008 #5

    Doc Al

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    Staff: Mentor

    What's the expression for the elastic potential energy stored in a stretched spring?
     
  7. Mar 4, 2008 #6

    tiny-tim

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    Homework Helper

    "Relevant equations"

    Hi gilly! :smile:

    Whoa! Don't do it all at once. Don't start incorporating one thing into another. :smile:

    You have two objects - Chris and the cord.

    What is the energy of each?

    Write them down separately. Then go from there. :smile:
     
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