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Homework Help: Deriving Kinematics Equations

  1. Feb 17, 2009 #1
    The Problem:
    Using V2x=V1x+ax(deltat)t and (delta)x=V1x(delta)t + 1/2ax(delta)t^2 derive the formula V2x^2=V1x^2+2ax(delta)t

    2. Relevant equations
    1st and 3rd x-component Kinematics Equations

    3. The attempt at a solution
    Ok, so I attempted to solve it, but it didn't work. I don't want the answer but could someone just push me in the right direction.
  2. jcsd
  3. Feb 18, 2009 #2


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    Homework Helper

    Solve the v2x = equation for time. Substitute that expression into the other equation to eliminate time. Simplify. You will find that
    will not have the delta t at the end.

    By the way, much easier if you leave out all those x's. These are just the one dimensional accelerated motion formulas from grade 11:
    V = Vi + at and d = Vi*t + 0.5*a*t^2
    and the one you are looking for is V^2 - Vi^2 = 2*a*d
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