Limitations of Using E to Find B in TEM Waves

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The discussion focuses on the limitations of using the equation H(r, t) = (1/v) ∇ × E(r, t) to find the magnetic field B from the electric field E in transverse electromagnetic (TEM) waves. Key limitations include the requirement for a charge-free medium and the necessity for E to represent a time-harmonic wave, typically a sine wave of a specific frequency. Additionally, the applicability of this formula in different mediums—such as lossless, lossy, or good conductors—poses further constraints. The conversation also touches on the relationship between E and B in TEM waves, clarifying that while they are perpendicular to each other and the direction of travel, not all plane waves qualify as TEM waves. Overall, understanding these limitations is crucial for accurate electromagnetic wave analysis.
yungman
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I have questions:
1) What is the limitation of using:

\vec H ( \vec r, t) =\frac 1 v \nabla \times \vec E(\vec r, t)\;\hbox { where }\; v= \frac 1 {\mu \epsilon}

I know for this formula to work, the medium has to be charge free. I want to know in what other cases I cannot use E to find B. I think the E has to be time harmonic wave which mean it is a sine wave of certain frequency \omega. Any other limitation?2) What is the limitation of using the formula in finding H of TEM wave in a medium ( lossless, lossy or practical good conductor )?

3) TEM wave only say E and B are perpendicular to each other and both perpendicular to direction of travel. Is plane wave part of the TEM wave?

Thanks

Alan
 
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I totally updated my original question in the first post.
 
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