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Homework Help: How long would it take to get to certain speed if you know Force forward and Mass?

  1. Feb 3, 2009 #1
    1. The problem statement, all variables and given/known data

    A frieght train has a mass of 1.5x10^7 kg. The wheels of the locomotive push back on the tracks with a constant net force of 7.5X10^5N, so the tracks push forward on the locomotive with a force of equal magnitude. (ignore aerodynamics and friction) how long would it take to increase the speed of the train from rest to 80km/h?

    2. Relevant equations



    3. The attempt at a solution

    So far I was able to calculate the acceleration:

    a=F/m

    a=7.5*10^5/1.5*10^7

    a=5*10^12m/s^2

    am I going in the right direction and how would I proceed?
     
  2. jcsd
  3. Feb 3, 2009 #2
    Re: How long would it take to get to certain speed if you know Force forward and Mass

    I believe you are on the right track. You need to use one of the kinematics equation though to find the time.
     
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