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Homework Help: Train/Car acceleration/speed problem

  1. Oct 21, 2007 #1
    1. The problem statement, all variables and given/known data
    A train is moving parallel and adjacent to a highway with a constant speed of 24 m/s. Initially a car is 49 m behind the train, taveling in the same direction as the train at 37 m/s, and accelerating at 4 m/s/s.

    What is the spped of the car just as it passes the train? Answer in units of m/s.



    2. Relevant equations

    I used 2aΔx=v^2-Vo^2


    3. The attempt at a solution

    I was solving for the car to get its final velocity (v^2) when it passes the train:
    2aΔx=v^2-Vo^2
    2(4m/s/s)(49m)=V^2-(37m/s)^2
    392 m^s/s^2=V^2-1369 m^2/s^2
    1761 m^2/s^2=V^2
    41.96427 m/s=V (for the car)

    my problem is that I don't know how to accomodate for the trains speed and how it effects the speed of the car as it passes. i know that the car will have to go faster but I just don't know how to approach the problem
     
  2. jcsd
  3. Oct 21, 2007 #2
    no love?
     
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