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Homework Help: Crash acceleration

  1. Oct 30, 2008 #1
    1. The problem statement, all variables and given/known data
    A person drives his SUV into a concrete wall. The car was initially moving East at 12.5m/s and the hood crumples a distance of 1.2m during the crash. What is the acceleration of the car during the crash? (don't forget directions when dealing with acceleration)

    I don't even know where to begin.
  2. jcsd
  3. Oct 30, 2008 #2
    What constant acceleration formulae do you know?
  4. Oct 30, 2008 #3
    almost all of them, i was given a big formula sheet that we are allowed to use in the test.
  5. Oct 30, 2008 #4
    So this is what we have:

    initial velocity (12.5ms-1)
    final velocity (0.0ms-1)
    distance (1.2m)

    What we need:


    What formula do you know that uses only these variables?
  6. Oct 30, 2008 #5
    Vf^2 = Vi^2 +2ad
  7. Oct 30, 2008 #6
    Perfect! Now we just need to re-arrange that formula and solve for a!
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