Question about electromagnetic waves -- Penetration vs. Frequency

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Discussion Overview

The discussion revolves around the penetration abilities of electromagnetic waves at different frequencies, specifically addressing why radio waves can penetrate walls while light cannot. The conversation explores theoretical aspects, material interactions, and the nuances of electromagnetic wave behavior.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants assert that high frequency electromagnetic waves are generally more capable of penetration than low frequency waves, questioning the apparent contradiction with radio waves and light.
  • Others argue that the transparency or opacity of a medium to electromagnetic radiation is influenced by the interaction between the radiation and the material, suggesting that penetration is not solely frequency-dependent.
  • A participant introduces the concept of the skin effect, noting that in metals, higher frequency waves penetrate less deeply, indicating that penetration can vary significantly based on the medium and context.
  • Another participant suggests that the energy of photons may play a role in penetration, proposing that more energetic particles are harder to stop, which could influence the discussion on penetration.
  • One participant highlights the complexity of the electromagnetic spectrum, noting that no single rule applies universally and that penetration depends on both frequency and the specific material being penetrated.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between frequency and penetration, with no consensus reached on a definitive rule governing this behavior. Multiple competing perspectives remain regarding the factors influencing penetration.

Contextual Notes

Limitations in the discussion include varying definitions of penetration, the dependence on specific materials, and the complexity of interactions between electromagnetic waves and different media. Unresolved mathematical or theoretical aspects are also present.

samy4408
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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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