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Homework Help: EM Waves basic problem

  1. Dec 7, 2011 #1
    1. The problem statement, all variables and given/known data


    2. Relevant equations
    Savg = Em * Bm / (2*μ0 * c)

    3. The attempt at a solution
    I solved for S avg without calculating inside the cos, but I got it right.

    The z and t is given, but is there the reason why you don't solve inside the cos, or is it the bug? it's makes me confused.

  2. jcsd
  3. Dec 7, 2011 #2


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    Homework Helper

    Savg = Em * Bm / (2*μ0 * c)

    What do Savg, Em and Bm mean?

  4. Dec 7, 2011 #3
  5. Dec 7, 2011 #4
    I see, I look at my teacher's notes and saw the exact equation.

    So to solve for Savg, it only cares about the maximum values right?
  6. Dec 7, 2011 #5
    Right, the result is independent of frequency or position.
  7. Dec 7, 2011 #6
    Thanks for your help.
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