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Homework Help: Constant speed/acceleration

  1. Feb 2, 2009 #1


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    1. The problem statement, all variables and given/known data

    At the instant the traffic light turns green, a car that has been waiting at the intersection starts ahead with a constant acceleration of 3.20 m/s squared. At the same instant, a truck, traveling with a constant speed of 20 m/s, overtakes and passes the car.
    A) How far beyond its starting point, does the car overtake the truck?

    B) How fast is the car traveling when it overtakes the truck?

    2. Relevant equations
    equations dealing with speed and acceleration

    3. The attempt at a solution
    so stuck!! Don't know how to start! Help!
  2. jcsd
  3. Feb 2, 2009 #2


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    Homework Helper

    Consider that the truck is going 20 at the moment the car starts accelerating.

    At what point - like how much later - will the distance the car accelerates (x = ½*3.2*t²) be the same as the truck (x = 20*t)?
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