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Homework Help: Average crush force exerted on a car

  1. Feb 24, 2009 #1
    1. The problem statement, all variables and given/known data
    2qd52ww.jpg


    2. Relevant equations
    Kinetic energy = Ke = (1/2)(mv^2) (joules - J)
    where m = mass (kg)
    v = velocity (m/s)

    3. The attempt at a solution
    What I was thinking was that the kinetic energy is divided uniformly over the distance d and hence
    Average crush force = mv^2 / 2d

    But I don't know how to prove that. Of course I could try to explain it with words, but I don't feel that it is enough.

    Thank you in advance.
     
  2. jcsd
  3. Feb 24, 2009 #2

    Delphi51

    User Avatar
    Homework Helper

    All of the KE is converted to work in crushing things: W = Fd = 1/2*m*v^2
     
  4. Feb 24, 2009 #3
    thank you, very helpful!
     
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