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Homework Help: Max speed and average speed

  1. Sep 8, 2009 #1
    1. The problem statement, all variables and given/known data

    (a) If the maximum acceleration that is tolerable for passengers in a subway train is 1.54 m/s2 and subway stations are located 816 m apart, what is the maximum speed a subway train can attain between stations? (b) What is the travel time between stations? (c) If a subway train stops for 21.0 s at each station, what is the maximum average speed of the train, from one start-up to the next?

    2. Relevant equations

    x= vot + 1/2 at^2 (i think? i'm not sure what else to use.. but time is not given)

    3. The attempt at a solution

    i don't know where to start :/
  2. jcsd
  3. Sep 8, 2009 #2


    User Avatar

    Staff: Mentor

    Think about it. How will the train move from station to station? Will it accelerate all the way? Why not? How much of the way will it be accelerating versus decelerating?
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