All Questions
15
questions
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53
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Photons and Bremsstrahlung radiation
When fast electrons goes into a target, part of their kinetic energy is converted into electromagnetic radiation, that we call Bremsstrahlung radiation, as they change their velocity. The energy ...
- 13
2
votes
4
answers
294
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How does an antenna emit photons at a specific frequency if the antenna is made up a specific metal (Al) for example?
My base assumptions...
An antenna emits energy over long distances in the form of photons.
A photon is emitted when an electron changes energy state from higher to lower levels.
A photon's "...
- 21
2
votes
1
answer
725
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Intensity of Compton scattering photons
In various sources (1, 2, 3, 4, to name a few) I have seen this graph shown below, that shows how intensity depends on the wavelength of the scattered photon $\lambda'$.
Now, I do understand what ...
- 35
2
votes
2
answers
79
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Why do electrons come to ground state even after giving absorbing energy?
Imagine you have a hydrogen placed under sunlight, now if we look at 1st shell of hydrogen, it has energy of $-13.6$ev now for 2nd shell we have energy of $-3.4$ev.
1st shell -> $-13.6$ev
2st ...
0
votes
1
answer
43
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Does the absorption of ionizing radiation increase the absorber temperature?
Let's say a gamma ray shielding material (assume water) has absorbed 1 joule of gamma ray ionizing radiation, does the absorbed 1 joule eventually end up as heat in this material?
I ask this question ...
- 3,916
2
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0
answers
83
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Work done by radiation on an electron
I'm studying quantum mechanics (already done with relativity) and I'm trying to understand the matter-radiation interactions. It's said everywhere that matter emits or absorbs photons but nowhere it's ...
- 97
42
votes
7
answers
5k
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Do nuclei emit photons?
Generally in text books they say that when a electron goes from high energy state to a lower energy state it emits photons.
My question is, it is possible that a proton that goes from high energy ...
- 445
0
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0
answers
49
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How to explain light beams in terms of wave theory?
How can we explain the formation of light beams in terms of wave theory?
According to wave theory, shouldn't the source point of beams emit radiation omnidirectionally, rather than a concentrated ...
- 533
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1
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2k
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Finding number of photons per second crossing an area with distance $d$ from a radiating point
Let's say I have a radio tower with frequency $v[HZ]$ and power output of $P[W]$ radiating uniformly across all directions, and I need to find the number of photons crossing an area of $1m^2$ per $...
- 151
-1
votes
1
answer
586
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Energy and intensity of a radiation
I have a question about the difference between energy and intensity of a radiation, I have read the energy is the one that the photons have of the radiation and the intensity increases with the number ...
- 29
1
vote
1
answer
127
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Why are photons not involved in $\beta -$ decay?
Theory of $\beta -$ emission exclusively considers participation of one $W -$ boson, one electron and one electron-antineutrino, but no photons. However Maxwell's electrodynamics require that during ...
- 290
2
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0
answers
210
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What force causes light to reflect off a surface?
Since $\vec F=d\vec p/dt$ and light consists of photons which experience a change in their momentum when they are reflected off a surface it follows that some force must act on those photons at the ...
- 297
6
votes
2
answers
4k
views
How many photons are there in free space on average
Estimates of the amount of for example "dark matter" are of interest to the cosmologists. However, I have never seen an estimate of how many "free" photons could be speeding about in the known ...
- 1,302
1
vote
2
answers
2k
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Is compton scattering only effective by x rayphotons and gamma ray photons
Can Compton scattering work with any other forms types of photons, and why was the the Compton Scattering experiment only done with x ray photons?
- 279
2
votes
1
answer
880
views
Is there a way to increase photon energy by decreasing its wavelength?
Can I decrease a photon's wavelength by a medium or a vacuum? Are there other ways of decreasing the wavelength?
- 279