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Homework Help: Acceleration problem

  1. Feb 1, 2009 #1
    1. The problem statement, all variables and given/known data
    The maximum deceleration of a car on a dry road is about 8.0 m/s^2.
    a. If two cars are moving head-on toward each other at 55 mi/h, and their drivers apply their brakes when they are 85m apart, will they collide?
    On the same graph, plot distance versus time for both cars.
    Assume x = 0 is the midpoint between the cars and t = 0 when the brakes are applied. Label the position versus time plot of the car with the positive velocity as x_1(t).


    2. Relevant equations



    3. The attempt at a solution
    a. no they will not collide, they will be 10 m apart when they stop.
    b. i think...
    (0,-42.5) and (3,-5) for x_1(t)
    and (0,42.5) and (3,5) for x_2(t)
     
  2. jcsd
  3. Feb 1, 2009 #2

    Delphi51

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    Homework Helper

    I get a little more than 10 - closer to 11 m apart.
     
  4. Feb 1, 2009 #3
    how would part b be solved?
     
  5. Feb 1, 2009 #4

    Delphi51

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    Homework Helper

    Use the same d = formula to find the distance at a series of times and plot them on a graph.
     
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