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Homework Help: Finding the acceleration when initial velocity is not known.

  1. Mar 7, 2010 #1
    1. The problem statement, all variables and given/known data

    In 2.0 s, a particle moving with constant acceleration along the x axis goes from x = 10 m to x = 50 m. The velocity at the end of this time interval is 10 m/s. What is the acceleration of the particle?


    2. Relevant equations
    kinematic equations


    3. The attempt at a solution
    i'm quite sure its an deceleration because if i calculate the average speed over the period of time i get 40/2 = 20ms-1, which is faster than the final velocity. I haven't find the way to calculate acceleration without initial velocity since every kinematic formula i know have Vi.

    Thanks
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Mar 7, 2010 #2

    Doc Al

    User Avatar

    Staff: Mentor

    Good. That means the acceleration is negative.
    Since you calculated the average velocity, use it to figure out the initial velocity.
     
  4. Mar 7, 2010 #3
    !@&(^#

    Thank you..silly me. (i actually went all the way to solve it graphwise...)
     
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