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Homework Help: Kinematic question

  1. Sep 11, 2016 #1
    1. The problem statement, all variables and given/known data
    A car accelerates at 1.95m/s2 along a straight road. It passes two marks that are 28.0m apart at times t=3.95s and t=5.20s. What was the car's velocity at t=0?

    2. Relevant equations


    3. The attempt at a solution
    t1=3.95s, t2=5.20s, d=28m, t=t12-t1=1.25s, a=1.95m/s2 v0=?
    28m=v0*1.25s+1/2*1.95m/s2*(1.25s)^2
    v0=21.2 m/s

    Could anybody tell me where have I done wrong?
     
  2. jcsd
  3. Sep 11, 2016 #2

    PeroK

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    You've tried to calculate the velocity at ##t = 3.95s##, although I think you made a mistake in that calculation.
     
  4. Sep 11, 2016 #3
    Thank you, now I see that the velocity I calculated is only the velocity at t= 3.95s:)
     
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