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Homework Help: Energy in electromagnetic waves

  1. Mar 26, 2007 #1
    1. The problem statement, all variables and given/known data

    Find the electric and magnetic field amplitudes in an electromagnetic wave that has an average energy density of 3.0 J/m3.

    2. Relevant equations

    u=1/2 eo E^2 + 1/(2uo) B^2
    u=eo E^2
    u=B^2 /uo

    3. The attempt at a solution

    I tried using these equations, but I wasn't getting the right answer. Do I have to change the units or am I just using the wrong equations?
  2. jcsd
  3. Mar 26, 2007 #2
    just kidding...I figured it out :)
  4. Apr 1, 2008 #3
    how do you do it?!
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