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Homework Help: Help with formula

  1. Sep 19, 2011 #1
    1. The problem statement, all variables and given/known data
    you are driving behind another car on the highway and both of you are going at a constant 80 km/h. the car in front of you slams on the brakes suddenly at max acceleration. 2.4 seconds later you apply your brakes (also at max acceleration). what is the minimum distance you can be away to avoid hitting the car in front of you?

    2. Relevant equations

    not sure..need help on this one..

    3. The attempt at a solution
    known information
    V1 = 80km/h
    v2 = 80 km/h
    t1 = 0 s
    t2 = 2.4 s
    d = ?
  2. jcsd
  3. Sep 19, 2011 #2


    User Avatar

    Staff: Mentor

    Hi dance_4dance, welcome to PF.

    From the instant that the brakes are applied, how far will the car in front travel before it stops? Assume that the acceleration is the variable a. The result will be an expression that contains that variable.
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