Timeline for Why are electromagnetic waves attenuated by thick barriers?
Current License: CC BY-SA 4.0
11 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Jun 21, 2020 at 17:19 | vote | accept | Matthew Inbox | ||
| Jun 21, 2020 at 17:19 | vote | accept | Matthew Inbox | ||
| Jun 21, 2020 at 17:19 | |||||
| Jun 21, 2020 at 9:15 | comment | added | HolgerFiedler | Why X-ray and radio waves can penetrate walls but light can not? | |
| Jun 21, 2020 at 9:10 | comment | added | HolgerFiedler | @Semoi Take an electric bulb (with no filament but a straight wire) and power it with a radio generator. You’ll get a radio wave, where the photons are polarized and are emitted periodically. What I never can agree methodically is the point, that a periodically emission is set equal to its wavelength. The zillion of photons, emitted from the skin of the wire are of very different wavelengths, sometimes in the range of X-rays. That is why it is dangerous to be in friont of a radar. physics.stackexchange.com/questions/90646/… | |
| Jun 21, 2020 at 8:56 | comment | added | NotMe | @HolgerFiedler: I was not aware of that. Furthermore, I don't know how one could produce a EM in the radio band from a thermal source. Could you please provide a reference which compares the two scenarios. | |
| Jun 21, 2020 at 5:26 | comment | added | HolgerFiedler | @ThePhoton To understand your last comment I’ll add that radio waves are radiation where zillions of polarized photons acting on the wall periodically. Radio waves are a special case of EM radiation. Using zillions photons from a thermal source with the same wavelength as in a radio wave does not the same with the wall. Simply no resonance happens and the photons get easier dissipated to heat. | |
| Jun 20, 2020 at 18:33 | comment | added | The Photon | @Matthew a single atom can have a narrow resonance. But when you combine many atoms together into a macroscopic object, those resonances spread out (because the levels they're based on are spread due to the Pauli exclusion principle) so that the macroscopic object can have strong absorption over a wide range of frequencies. | |
| Jun 20, 2020 at 17:27 | history | edited | NotMe | CC BY-SA 4.0 |
add model
|
| Jun 20, 2020 at 17:26 | comment | added | Matthew Inbox | Does that mean an atom can absorb photons with energies less than its smallest energy gap? How does that wok? | |
| Jun 20, 2020 at 17:21 | history | edited | NotMe | CC BY-SA 4.0 |
add model
|
| Jun 20, 2020 at 17:02 | history | answered | NotMe | CC BY-SA 4.0 |