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Mechanics. Speed.

  1. Feb 14, 2014 #1
    One question. In the text


    author calculate

    ##y′_β=−10^7a^t lna##
    (see pages 4 and 5)
    why minus sign in derivative? ##y_{\beta}'## is speed. And they use minus sign as I see just to obtain positive quantity for ##y′_β=10^7a^t lna##. Is there any relation between that sign and motion of the particle? Particle moves in the some law of geometric progression.
    Last edited: Feb 14, 2014
  2. jcsd
  3. Feb 14, 2014 #2


    User Avatar

    Staff: Mentor

    This link is not complete. It gives me a "Not Found" error in my Web browser. Could you please post a correct version of it?
    Last edited by a moderator: May 6, 2017
  4. Feb 14, 2014 #3
    Try now.
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