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Work, Velocity & Force vectors Help

  1. Sep 13, 2010 #1
    This is probably more of a math question, but it pertains to physics.

    Today in Classical Mechanics the professor was showing the following,

    F . dr = (MV2^2)/2 - (MV1^2)/2

    but in great length, one of the steps along the way I did not understand how he did it... it was this:

    screw latex, if someone could please post a link to somewhere on the forums that shows how to use latex properly, I can't use it to save my life...
    here is the step with good old microsoft:

    [PLAIN]http://mynqa.com/Cargo/unk.bmp [Broken]

    My questions are, where did the number 2 come from in the denominator? Also, how did he bring in the velocity vector into the derivative like that?

    Thanks for any help.
     
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Sep 14, 2010 #2

    gabbagabbahey

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    See my sig :wink:

    Just apply the product rule to the right-hand side of the equation...
     
    Last edited by a moderator: May 4, 2017
  4. Sep 14, 2010 #3

    mathman

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    It is essentially the vector equivalent of the derivative of a square.

    d/dt(x2)=2xdx/dt
     
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