EM Wave Boundary Layer Question

AI Thread Summary
The discussion centers on the transition of electromagnetic waves from air into a conductive medium, specifically regarding whether the wavelength changes instantaneously or if a boundary layer exists. It is noted that for low-frequency waves, such as those with a wavelength of 3000 km transitioning to 158 m, the wavelength changes at the interface without a significant transition region. The conversation highlights that in conductive media, the wave will experience attenuation over a finite distance. Additionally, there is curiosity about potential near-field effects similar to those observed in antennas, suggesting that interesting physics could occur over a large boundary due to the wavelengths involved. Overall, the inquiry seeks resources on the behavior of waves in boundary layers during such transitions.
DJungquist
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I understand application of Snell's law for transition from one medium to another but I have a question regarding this model. When an electromagnetic wave transitions from air into a conductive medium does the wavelength change instantaneously as the theory seems to imply or is there a boundary layer which is ignored because at usual wavelengths the boundary transition is so small it doesn't matter?

The case I am interested in is a low frequency wave which has a wavelength of 3000 km into a medium that reduces the wavelength to 158 m. So is there a transition region? If so, can someone point me to a resource that discusses the behavior in the boundary layer as the wavelength changes.
 
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The wav length changes at the interface wilth no transition region.
If it is a conductive medium, the wave will attenuate in a finite distance.
 
Meir Achuz said:
The wav length changes at the interface wilth no transition region.
If it is a conductive medium, the wave will attenuate in a finite distance.

I understand the attenuation will be a function of frequency, permeability and conductivity. I was just wondering if there was something similar to a near field effect on an antenna where in the first wavelength you get some interesting physics. Given the wavelengths involved if there was a near field like effect it would be over a fairly large boundary.
 
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