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Homework Help: Acceleration. linear motion. i'm stuck

  1. Dec 11, 2008 #1
    acceleration. linear motion. i'm stuck!!!

    1. The problem statement, all variables and given/known data
    a train moves at a velocity of 60 m s-1 and stops after a distance of 600m. what is its deceleration?


    2. Relevant equations
    v=s/t



    3. The attempt at a solution
    this is my working:
    u= 0 m s-1
    v= 60 m s-1
    s= 600 m

    v=s/t
    60=600/t
    t=10 s

    ...and i'm stuck here. please help!!!
     
    Last edited: Dec 12, 2008
  2. jcsd
  3. Dec 11, 2008 #2

    rl.bhat

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    Re: acceleration. linear motion. i'm stuck!!!

    The velocity is not uniform. So you can't use v = s/t. And here initial velocity is 60 m/s and final velocity is 0. Use appropriate kinamatic formula which relates initial velocity, final velocity , acceleration and displacement.
     
  4. Dec 12, 2008 #3
    Re: acceleration. linear motion. i'm stuck!!!

    what formula? tell me and i'll try to work it out!
     
  5. Dec 12, 2008 #4

    rl.bhat

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    Homework Helper

    Re: acceleration. linear motion. i'm stuck!!!

    v^2 - u^2 = 2as
     
  6. Dec 12, 2008 #5
    Re: acceleration. linear motion. i'm stuck!!!

    My favorite for finding acceleration is a([tex]\Delta[/tex]x)=(1/2)([tex]\Delta[/tex]V2)
     
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