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E&M - Electric Field Intensity in Microwave

  1. Sep 25, 2006 #1

    This problem has me stumped and I keep thinking that I'm missing something simple. The question gives us a simple model for modelling a microwave. We consider a plane wave travelling through an object in the microwave (in the z direction), with no reflection.

    So, the general form should be; [tex]E(z) = E_0e^{-yz}[/tex]

    We are given that the waves radiate 500W of power at f = 2 GHz in a cylindrical volume with radius r=4. The object has an outer layer 5mm thick. We are also given [tex]\epsilon_r[/tex] and [tex]\mu_r[/tex]. And we have to find the peak electric field intensity at the top of the surface.

    Any ideas where to start on this one? I assume it's asking for E0, but I don't know what theorems I should apply to get that one. Maxwell's equations only give me the general solution I posted above. I tried doing boundary conditions, but that didn't get me anywhere either. I have a feeling it may have something to do with the power and the frequency, and possibly the Poynting Theorem. And maybe I should integrate [tex]P = 1/2 \int |E|^2 dV[/tex] over the cylindrical volume and set P = 500 W?

    Am I on the right track? Thanks for any help you can offer!
  2. jcsd
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