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What is a transformation law?

  1. Jun 15, 2014 #1
    I really don't understand what it is and what is the use of constant, like in this equation of transformation.
    x=k(x' + vt).
    The equation can also be good if it is just like this,
    x=x' + vt

    Thank you.
  2. jcsd
  3. Jun 15, 2014 #2


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    Gold Member

    So you are saying the $$F=\frac{m_1m_2}{r^2}$$?

    That is certainly not true.
    Do you believe that ##F=x##?(Hookes law)
    Yes this is valid for a elastic constant of 1 but not valid for any other constant.
  4. Jun 15, 2014 #3
    No this is about theory of special relativity. It uses transformation law to derive the equations of Lorentz transformation. And my question is about the use of the constant, I mean how they thought that there must be a constant such that this equation holds good at high speeds.
  5. Jun 15, 2014 #4
    Are you sure there is constant "k"?
    Cause I read today Lorentz,and I saw nothing about that?
    Also if there is,then what is the value of "k" ?
  6. Jun 15, 2014 #5


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    Staff: Mentor

    The Lorentz transformation for x is
    $$x^\prime = \frac{x - vt}{\sqrt{1 - v^2/c^2}}$$
    You should be able to read off the value of k from that equation. (We usually call it ##\gamma##.)
    Last edited: Jun 15, 2014
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