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Homework Help: Uniform accelerated motion

  1. Dec 16, 2008 #1
    1. The problem statement, all variables and given/known data

    1. A train moving at a speed of 30 m/s slows down to 10m/s in 30s. How far had the train gone before it's speed was reduced from 30m/s to 20 m/s?

    2. Relevant equations

    D= Vi times T + at(squared) divide it by 2

    3. The attempt at a solution
    None yet. Please help me with the solution
  2. jcsd
  3. Dec 16, 2008 #2


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  4. Dec 16, 2008 #3
    Honestly im having a hard time figuring out what the initial velocity is.. and the acceleration
  5. Dec 16, 2008 #4


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    You can figure the "a" simply by using the relationship that ΔV = a*t That Δ v is (10 - 30) = -20 = a*t

    Using the V2 = ... formula then your final speed is 10 m/s and you Initial is 30 and your acceleration is negative because it's slowing you down to 20, then you can figure x.
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