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Homework Help: How to find the amplitudes and polarisation of travelling waves

  1. May 31, 2012 #1
    1. The problem statement, all variables and given/known data

    Plane monochromatic waves are propagating in free space parallel to the x-axis
    in both positive and negative directions. At the origin the fi eld strengths are
    given by:
    Ez = E0 cos wt Ey = 3E0 cos wt
    cBz = E0 cos wt cBy = E0 cos wt
    Find the amplitudes and polarisations of the forward and backward travelling
    waves, and the net energy flux


    3. The attempt at a solution

    I only get the backward amplitude which is 2E0 parallel to y-axis and the net flux which is E0^2/Z0

    Can anyone help to find the forward amplitude?
     
  2. jcsd
  3. Jun 1, 2012 #2
    $$ y=A\cos\left(\omega t+\phi\right) $$

    Isn't the answer quite easy to derive now?:biggrin:
     
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