B Question about electromagnetic waves -- Penetration vs. Frequency

AI Thread Summary
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.
samy4408
Messages
62
Reaction score
9
TL;DR Summary
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
 
Physics news on Phys.org
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.
 
  • Like
Likes rude man and vanhees71
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.
 
Thread 'Gauss' law seems to imply instantaneous electric field propagation'
Imagine a charged sphere at the origin connected through an open switch to a vertical grounded wire. We wish to find an expression for the horizontal component of the electric field at a distance ##\mathbf{r}## from the sphere as it discharges. By using the Lorenz gauge condition: $$\nabla \cdot \mathbf{A} + \frac{1}{c^2}\frac{\partial \phi}{\partial t}=0\tag{1}$$ we find the following retarded solutions to the Maxwell equations If we assume that...
Dear all, in an encounter of an infamous claim by Gerlich and Tscheuschner that the Greenhouse effect is inconsistent with the 2nd law of thermodynamics I came to a simple thought experiment which I wanted to share with you to check my understanding and brush up my knowledge. The thought experiment I tried to calculate through is as follows. I have a sphere (1) with radius ##r##, acting like a black body at a temperature of exactly ##T_1 = 500 K##. With Stefan-Boltzmann you can calculate...
Thread 'Griffith, Electrodynamics, 4th Edition, Example 4.8. (First part)'
I am reading the Griffith, Electrodynamics book, 4th edition, Example 4.8 and stuck at some statements. It's little bit confused. > Example 4.8. Suppose the entire region below the plane ##z=0## in Fig. 4.28 is filled with uniform linear dielectric material of susceptibility ##\chi_e##. Calculate the force on a point charge ##q## situated a distance ##d## above the origin. Solution : The surface bound charge on the ##xy## plane is of opposite sign to ##q##, so the force will be...
Back
Top