I'm attempting to calculate the above, but I'm stuck.(adsbygoogle = window.adsbygoogle || []).push({});

What I have thus far:

intensity is the time average of the poynting vector, where the poynting vector is the cross product of the E and B fields.

Using the given expressions, I get:

[tex] \frac{\sqrt{a^2 + b^2}}{\mu \omega} E_0^2 \exp(-2bz) \frac{\cos\phi}{2} [/tex]

where a and b are the real and imaginary parts of the complex wave number, k.

[tex] \phi [/tex] is of course the phase angle between the E and B fields (since this is a conducting medium the B field lags).

I'm supposed to show that the intensity is

[tex] \frac{a}{2 \mu \omega} E_0^2 \exp(-2bz) [/tex]

but I dont know how to proceed.

any help would be greatly appreciated.

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# Homework Help: Intensity of EM waves in a conducting medium

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