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How do I get acceleration, distance, and time?

  1. Apr 15, 2015 #1
    1. The problem statement, all variables and given/known data
    While driving your car at 20 m/s (about 45 mph) along a country road one night, you suddenly see a deer in your headlights. Your car's mass is 1200 kg, and the coefficients of friction between its tires and the asphalt road are 0.4 and 0.6.
    If you slam on your brakes and lock the wheels, how far will you skid before stopping if the road is level?
    I have no idea on how or where to start.
    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Apr 15, 2015 #2
    Take a second and step back, then write down what each number of information represents. then see what equations use the information. Then make an attempt to solve
  4. Apr 15, 2015 #3


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    Certainly you know something.

    Newton's Laws, friction, acceleration, velocity, time ...

    How are they related?
  5. Apr 15, 2015 #4
    Try using ΣF=Δp/Δt. You should find Δt from this equation. Then you use this one to find the acceleration: v=u-at. Can you find out what comes next?
    Last edited: Apr 15, 2015
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