B Question about electromagnetic waves -- Penetration vs. Frequency

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High-frequency electromagnetic waves generally penetrate materials differently than low-frequency waves, with penetration depending on the interaction between the waves and the medium. While high-energy waves can penetrate more, the skin effect in metals shows that higher frequencies actually penetrate less deeply. The transparency of materials, such as glass, is determined by how electromagnetic radiation interacts with the material's atomic structure. The electromagnetic spectrum is vast, and no single rule governs penetration across all frequencies and materials. Ultimately, the penetration ability of electromagnetic waves varies based on frequency and the specific properties of the medium.
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a problem with an information i read.
I read in a book that high frequency electromagnetic waves are more able to penetrate than low ones , so why radio waves can penetrate walls when light cannot?

2022-03-07 14_08_16-5.1 Nature of Waves _ _ AP® Physics 2 - Part 3_ Optics and Modern Physics ...png
 
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It depends what exactly you mean by penetration. This statement looks to me like it is not entirely correct.

If we take penetration of EM into metal plates, the so called skin effect/depth, it is inversely proportional to frequency, that is the higher the frequency the less the depth the EM wave penetrates into the metal.
 
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samy4408 said:
I read in a book that high frequency electromagnetic waves are more able to penetrate than low ones , so why radio waves can penetrate walls when light cannot?
I think it is true if photons rather than EM waves are considered. E = h⋅u ;
More energetic particles are harder to stop.
 
What are the other two rules? The electromagnetic spectrum is so huge that no single rule applies to all the region of the EM waves. You can find examples where the high frequency penetrates more and where it penetrates less. You already found one that disproves the "rule". Depends on what you compare. And also, on the material that the wave penetrates.
 
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