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Homework Help: Amplitude of EM wave

  1. Dec 5, 2005 #1
    Suppose I have an eliptically polarizied EM wave, whose electric field can be written as

    [tex]\vec{E}=A\cos(kz-\omega t)\vec{e}_x+B\sin(kz-\omega t)\vec{e}_y,[/tex]

    where the constants [itex]A[/itex] and [itex]B[/itex] are amplitudes of the [itex]x[/itex] and [itex]y[/itex] components of the beam, respectively.
    How would I report the amplitude of the whole beam?

    (Please note that I am not looking for intensity of the beam -- I know how to report that).
     
    Last edited: Dec 5, 2005
  2. jcsd
  3. Dec 5, 2005 #2

    mezarashi

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    Homework Helper

    This question is similar to asking, what is the magnitude of a voltage source with time function:

    [tex]V = A\cos (\omega t) + B\sin(\omega t)[/tex]

    There are two out of phase components superimposed on each other. In my opinion, it would only make sense to have some RMS value if you are doing power calculations.
     
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