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Homework Help: Problem with acceleration and distance!

  1. Feb 24, 2012 #1
    1. The problem statement, all variables and given/known data
    v, a1, a2 are the needed variables

    A car is traveling in the +x direction with a speed of v when the driver notices a car that is stopped in front of him at distance d. In order to avoid a collision, he immediately applies the brakes resulting in an acceleration of -a1. At the same time, the parked car starts to accelerate in the +x direction with an acceleration of a2. Determine the distance d in terms of v, a1 and a2 if the cars are to just barely avoid a collision.
    The only hint I have is: think about the position and velocity of each car. What is required to just barely avoid a collision.

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Feb 24, 2012 #2


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    Homework Helper

    The hint is telling you provided the cars are traveling at the same speed the two cars could contact each other.

    I would start by drawing velocity time graphs for the two cars - well actually the front of the travelling car and the rear of the stopped car
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