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Same Question as before.

  1. Oct 18, 2005 #1
    This was the original question: A high jumper falling a 3.9 m/s, lands on a foam pit and comes to rest, compressing the pit a distance of 0.43 m. If the pit is able to exert an average fource of -1100 N on the high jumper in breaking the fall, what is the jumper's mass?
    But Im not sure if Im supposed to multiply or divide 0.43m and 3.9 m/s
    Ive narrowed the answer down to either 1845 kg or 121 kg.
  2. jcsd
  3. Oct 18, 2005 #2
    Well, 1845kg is about 4000lbs.. whereas 121kg is about 260lbs..
  4. Oct 18, 2005 #3
    Ive been leaning towards 121kg mainly because of that, but I just wanted to be sure.
  5. Oct 18, 2005 #4
    Show your work and I can look over it.
  6. Oct 18, 2005 #5

    Doc Al

    User Avatar

    Staff: Mentor

    Sounds like you're guessing? :grumpy:

    (1) What's the acceleration?
    (2) Apply Newton's 2nd law to find the mass. (Use the net force.)
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