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Homework Help: A 50cm wavelength EM wave in air has 50mW/m^2 of energy.

  1. Dec 11, 2011 #1
    1. The problem statement, all variables and given/known data

    A 50cm wavelength EM wave in air has 50mW/m^2 of energy.
    what is the frequency?
    what is the average E field?
    What is the B field strength?
    What would be the λ in water?


    2. Relevant equations

    I found the λ. How do I find it in water

    3. The attempt at a solution

    E = √50/.5*ε°*c... is that correct?
    frequency = 17.3 Khz
     
  2. jcsd
  3. Dec 11, 2011 #2

    Kurdt

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    Staff Emeritus
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    Gold Member

    Re: wavelength

    You will have to use the index of refraction for water.
     
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