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Homework Help: Moving about, velocity, speed, of objects

  1. Sep 21, 2008 #1
    i have this killllerrr question i need some help on. idno what to do..

    1. The problem statement, all variables and given/known data
    A train is moving at a constant speed of 20ms per second along a striahgt, level track when its last carriage is released. This carriage comes to a rest after continuing for 200m along the track. the speed of the train remains constant.

    a.) what was the acceleration of the carriage.
    b.) how long did it take for the carriage to come to a rest?
    c.) how far ahead of the carriage was the train when the carriage stoped?

    2. Relevant equations
    i got the first 2, using v^2 = u^2 + 2ar, and v = u + at

    idno how to get the last answer.

    3. The attempt at a solution
    no idea.
  2. jcsd
  3. Sep 21, 2008 #2


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    Homework Helper

    Find the distance travelled by the carriage after it got disengaged from the train. Also find the distance travelled by the train during the same period of time. See what to do next?
  4. Sep 21, 2008 #3
    how do i know when it got disengaged?
    cos it just says the carriage got disengaged from a train goin 20msper second :S
  5. Sep 21, 2008 #4
    no wait!
    hahah i got it man

    thanks bud
    what i did was
    r = ut + 1/2at^2

    because i got the time from part B

    turned out to be 200metres ahead :D

    thanks man
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