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Awwwhelp please

  1. Apr 11, 2004 #1
    Could someone help me set up this problem and give some helpful hints.

    From what maxium height can a 75-kg person jump without breaking the lower leg bone on either leg? Ignore air resistance and assume the CM of the person moves a distance of .60m from standing to the seated position (that is, in breaking the fall). Assume the breaking strenght (force per unit area) of bone is 170 * 10^6 N/m square, and its smallest crosssectional area is 2.5 * 10^-4 m square.
     
  2. jcsd
  3. Apr 11, 2004 #2

    enigma

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    Have you tried it yet?

    Conservation of energy.

    [tex]\int{Fds} = mgh[/tex]
     
  4. Apr 11, 2004 #3
    no, because I need help with the set up for each section...I have been out for a couple days so I don't fully understand the problem. If I knew the equations for each step, I could take it from there.
     
  5. Apr 11, 2004 #4

    enigma

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    I more or less gave it to you already.

    You know the breaking stress, and the bone's area. Stress is force divided by area. ->solve for force.

    You know the force and the distance that force can act on. You know the mass, you know gravity, solve for height.
     
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