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Car stopping on a dime

  1. Feb 2, 2012 #1
    What is the g-force on a car, initially traveling at 55 mph, when stopping across the diameter of a dime?
     
  2. jcsd
  3. Feb 3, 2012 #2

    Pythagorean

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    convert mph to mps, find the acceleration from change in velocity, multiply by mass, divide by g.
     
  4. Feb 3, 2012 #3

    Pythagorean

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    Find acceleration from change in velocity over given distance, that is.
     
  5. Feb 3, 2012 #4
    Would it not be appropriate to solve a system of equations, d=1/2 * a * t^2, d = 17.91 mm, and a * t = 55 mph?

    Doing this I get about 16.9 kilometers / s^2, or 1721g.
     
    Last edited: Feb 3, 2012
  6. Feb 3, 2012 #5

    Pythagorean

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    [tex]a = \frac{v^2 - v_0^2}{2d}[/tex]

    but [tex]v_0 = 0 [/tex] (in my ref frame : )

    so

    [tex]a = \frac{v^2}{2d}[/tex]

    Of course, this assume constant acceleration...
     
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