Questions tagged [absorption]
A transition by which the energy of at least one photon is completely transferred to a material.
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How does one account for the momentum of an absorbed photon?
Suppose I have an atom in its ground state $|g⟩$, and it has an excited state $|e⟩$ sitting at an energy $E_a=\hbar\omega_0$ above it. To excite the atom, one generally uses a photon of frequency $\...
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How are photons "consumed"?
I have very little background in physics, so I apologize if this question is painfully naive.
Consider the following thought experiment: an observer is in a closed room whose walls, floor, and ...
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Why don't absorption and emission lines cancel out in our Sun?
I was looking at this answer on why absorption lines and emission lines don't cancel out:
An experiment shining light on the material and looking at the
reflected spectrum will see absorption ...
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Where do photons go when they are absorbed?
The answer I usually get (and I'm paraphrasing here) is that they disappear and are instead absorbed as heat energy.
But I find it hard to believe that the photon simply "disappears." Common sense ...
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How precise must the energies match for absorption of photons?
According to Quantum Mechanics, in order for an atom to absorb a photon the energy of the photon must be precisely that of a "jump" between energy states of the atom.
How precise must it be?
If I ...
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Photoelectric effect absorption coefficient decreases with energy, why?
Consider the diagram below:
(Author: Joshua Hykes source: Wikipedia)
From this diagram we can see that the absorption coefficient for the photoelectric effect generically decreases with the increase ...
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How can an object absorb so many wavelengths, if their energies must match an energy level transition of an electron?
I believe I have a misunderstanding of some principles, but I have not, even through quite a bit of research, been able to understand this problem.
My current understanding of transmission, ...
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Why do bass tones travel through walls?
I was in the shower while my roommate was listening to music and got to thinking about the fact that I could only hear the bass and lower drums through the walls. Why is this? The two possibilities I ...
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Why do lines in atomic spectra have thickness? (Bohr's Model)
Consider the atomic spectrum (absorption) of hydrogen.
The Bohr's model postulates that there are only certain fixed orbits allowed in the atom. An atom will only be excited to a higher orbit, if it ...
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How do Black Bodies Absorb and Emit Radiation? [duplicate]
I have learnt how the gases of elements are able to absorb only certain wavelengths of EM radiation corresponding to the energy transitions between energy levels of orbitals. Furthermore, these ...
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Why can't we see gases?
I am not sure what causes gas molecules to be invisible.This question may look silly but I really want to know the story behind it.
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Is the Energy of an absorbed photon exactly the energy of the band gap?
I was wondering, if the Energy of a Photon which is absorbed by an Electron, hast to be exactly the Energy of the bound gap.
So if i have two energy levels in an atom $E_2$ and $E_1$, does my ...
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Excitons - Increase in absorption
I have consulted a book by Mark Fox on Optical Properties of Solids, and it states:
" The absorption of a photon by an inter-band transition in a semiconductor or insulator creates an electron in ...
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Why do X-rays go through things?
I always heard that the smaller the wavelength, the more interactions take place. The sky is blue because the blue light scatters. So why is this not true for X-rays, which go through objects so ...
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Can a photon be absorbed by a proton?
When incident light passes through a hydrogen gas, for example, does it have 50% chance (since it's a 1:1 ratio of protons to electrons) of getting absorbed by the proton? Any chance at all? If no, ...
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