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Phase change of reflected wave

  1. Nov 7, 2007 #1
    what do we mean when we say that light wave suffers a phase change of [tex]\pi[/tex] when it gets reflected and why does that happen
     
  2. jcsd
  3. Nov 7, 2007 #2

    Meir Achuz

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    If it is reflected by a conductor (to make it easy), the E field must be zero at the conductor.
    Thus mean that the reflected E field must be equall and opposite to the incident E field.
    That is [tex]{\vec E}_R=-{\vec E}_I[/tex].
    In complex notation, -E=exp(i pi) E.
     
    Last edited: Nov 7, 2007
  4. Nov 7, 2007 #3

    G01

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    A phase change of Pi means, in essence, that the wave is flipped upside down after it is reflected. That is, if you have a crest of a wave reflecting off of a boundary, after the reflection, that crest will become a trough. This is due to the electromagnetic boundary conditions at the surface of reflection as Meir Achuz pointed out.
     
  5. Nov 7, 2007 #4
  6. Nov 7, 2007 #5
    thank u
     
  7. Nov 13, 2010 #6
    how do I calculate amplitude and phase for reflected wave? Is the change in phase occurs in all objects
     
  8. Nov 13, 2010 #7

    ehild

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