EM waves in matter (electrodynamics)

maverik
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I'm having some trouble understanding this module. It would be great if anyone could help.

In a homogeneous nonconduction region where μr = 1, find εr and ω if

E=30(pi)e[i(ωt-4/3y)] in z direction

H=0.1e[i(ωt-4/3y)] in x direction

I am to understand that for a homognous nonconduction region D=εE and ε=εrε0. However, just equating εr=D/ε0E doesn't seem right. Judging from textbooks and notes I am assuming i must use Maxwell's eqn's for a homogenous nonconducting region, but I'm not sure where to get started. Similarly for ω i can equate ω=(ln|B/10μ0|+4/3y)/t. But again, I'm not sre that this is right.

If anyone could point me in the right direction that'd be great!
 
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maverik said:
I am to understand that for a homognous nonconduction region D=εE and ε=εrε0. However, just equating εr=D/ε0E doesn't seem right. Judging from textbooks and notes I am assuming i must use Maxwell's eqn's for a homogenous nonconducting region, but I'm not sure where to get started.

There's nothing wrong with saying \epsilon_r=\frac{D}{\epsilon_0 E}...but since D is not given to you, you'll need to express it n terms of the parameters that are given to you in the problem (like \omega, y and t)...to do that, take a look at what \mathbf{\nabla}\times\textbf{H} is...

As for finding \omega, try calculating \mathbf{\nabla}\times\textbf{E} and compare it to the relevant Maxwell equation...
 
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