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Homework Help: Displacement of a car before it stops

  1. Nov 25, 2007 #1
    1. The problem statement, all variables and given/known data

    A 2410 kg car traveling to the west at 22.6 m/s slows down uniformly.

    It takes 6.13355 seconds for the the car to come to a stop if the force on the car is 8880N to the east.

    What is the car's displacement during the time it takes to stop? Answer in m


    2. Relevant equations

    d = vit + .5at^2

    3. The attempt at a solution

    Fnet=m*a=F
    =(2410)a=8880
    a=3.68m/s2
    d=vit-.5at^2
    =22.6*6.13355+(.5)(3.68)(6.13355)^2
    =207.8387m

    its not 207.8387 or 69.396
     
  2. jcsd
  3. Nov 25, 2007 #2

    rl.bhat

    User Avatar
    Homework Helper

    =22.6*6.13355+(.5)(3.68)(6.13355)^2
    Motion is retarding . So acceleration should be negative.
    =22.6*6.13355-(.5)(3.68)(6.13355)^2
     
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