All Questions
Tagged with electromagnetic-radiation photon-emission
45
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Will an electron release energy when it is added into an atom for which electron affinity value is negative (endothermic)?
According to my understanding, when an electron is added into an atom, it emits energy in the form of photons because it is a form of de-excitation or relaxation. This is when electron affinity will ...
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How many photons pass through us every second?
I just read this answer https://physics.stackexchange.com/a/229374, which says that, when a magnet rotates, photons are emitted with wavelength $λ=c/f$, where $f$ is the frequency of rotation. And ...
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Is luminescence from impact of fast neutral atoms/molecules on a suitable substance known?
Cathodoluminescence is emission of photons by electrons impacting on a luminescent material.
The Rutherford scattering experiments detected impacting helium nuclei on a phosphor screen.
Many other ...
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What happens to light absorbed by a body with color?
As everyone knows, an object with color appears that way because it reflects its specific color(s). Textbooks tell us other colors are absorbed. Now, here's the question: what happens to the absorbed ...
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Stimulated emission semiclassical model for atom recoil
In the context of Saturated absorption spectroscopy, I'm having trouble modeling stimulated emission, and getting the result that is written in articles, such as this article. I tried to use a non-...
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Blackbody Radiation vs Emission Line spectrum
A perfect blackbody has a predicable emission pattern in terms of both intensity and color, given by Planck´s law.
Similarly, elements such as Hydrogen or Helium will emit specific wavelengths when an ...
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2
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2
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What is the interplay between radiation and photon creation?
While trying to provide an answer to this question, a question popped into my mind. When a charge accelerates, is there always a photon associated with that radiation, or multiple photons? For ...
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How "wide" are absorption and emission lines?
There are various absorption lines that correspond to the difference in energy levels between electron orbits. E.g. the https://en.wikipedia.org/wiki/Lyman-alpha_line correpsonding to the difference ...
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Photons: Why not wave only? [duplicate]
It seems that Einstein's 1905 paper "Concerning an Heuristic Point of View Toward the Emission and Transformation of Light" notes the discrete quanta of light energy, an idea that leads to ...
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Luminescence vs. X-ray emission
When a target atom is struck by some kind of radiation (for example, a $\text{MeV}$ proton), electrons from lower shells are kicked off and replaced by electrons from higher shells, which in return ...
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If all matter can emit at all wavelengths, can all matter absorb at all wavelengths too?
Based on Planck’s law all matter can emit at all wavelengths at different intensities dependent of temperature. I was wondering if this holds true, does all matter absorb all wavelengths too, at ...
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Do all matter emits radiation at all wavelengths? [duplicate]
Does all matter emit radiation at all wavelengths? Do gasses also emit radiation at all wavelengths since they have a specific emission spectrum? Shouldn't they only emit radiation according to their ...
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Trouble with Einstein coefficients - what is the meaning of the transition probability?
Perhaps it seems to be a not very intelligent question, but I am unfortunately not able to understand what the probability per second that a molecule will absorb a photon is, as part of the theory of ...
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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 ...
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102
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Can Two Electromagnetic waves cancel each other if it 180 degree phase moving in same direction?
If we can send two electromagnetic waves -180 degree out of phase- in same direction, then the interaction of this wave with air molecules will be less due to the low intensity of the combination. So,...
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How exactly does one reaction of nuclear fussion exactly produce EMR of different types? [closed]
Electromagnetic radiation from sun is more likely produced by the nuclear fusion, and at a go radiation is released but how is it possible for different types of radiation to be produced such as, ...
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Where can I find data of a UV blocking glass absorption filter absorbing the visible light and re-emitting the energy as a photon of NIR?
If I understand correctly, a UV Transmitting, visible light absorbing colored glass absorption filter absorbs the visible light energy and re-emits it as near IR. On Oct 16, 2013 in How does Infrared ...
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What is the relationship between emissivity $\varepsilon$ and the imaginary part of relative permittivity constant $\epsilon^{''}_{\rm r}$ if any?
In terms of the Stefan-Boltzmann law a body that does not absorb all incident radiation emits less total energy than a black body and is characterized by an emissivity $0<\varepsilon <1$ such ...
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Why do some electromagnetic waves have more than one photon?
I know that the energy of an EM wave is equal to nhv, where n is the number of photons, but why/how do the number of photons in a wave vary? If a single atom emits an EM wave with an energy of 100 ...
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Why do objects emit color even if they are not under the influence of heat?
Do correct me if I am wrong:
I am assuming that, when you heat a material, say iron, the electrons gain thermal energy and jump to a higher energy level. When they fall back, they emit photons of ...
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Why is radiation of a particular frequency most intense in black body radiation?
Why is radiation of a particular frequency more intense than other frequencies in black body radiation? Does this mean that most electrons in the object are emitting photons of that frequency?
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Are photons really 'particles' of light? [duplicate]
In Einstein's Photon Theory of Light, he proposed that light consists of distinct chunks or distinct packets of energy called photon and the energy of a photon is given by :
$E=hν$
where $ν$ is the ...
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How is light emitted by an incandescent lamp?
I am looking for better understanding of how light is produced in an incadescent lamp. More specifically: how is the kinetic energy of electrons converted to light?
Are we dealing with interband ...
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Feynman Lectures on Physics Vol-I 32-3 Radiation damping. How does this classical result relate to QM?
The following is from https://www.feynmanlectures.caltech.edu/I_32.html#Ch32-S3
Now let us actually calculate the Q of an atom that is emitting light—let us say a sodium atom. For a sodium atom, the ...
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What are the lowest and highest energetic (electron shell) emission lines considering ANY molecule or atom (observed & theoretical)?
I am making this public interactive infographic of the electromagnetic spectrum on the web. In it I visualize all interactions of EM waves with matter. And I try to display boundaries for every ...
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Can inner electrons get excited? Can an already excited electron get excited again without first dropping to a lower energy level?
Is it only the valence electrons that can get excited or can the inner electrons get excited too?
Plus, say for example can a electron of a hydrogen atom go from n=2 to n=3 without first returning to ...
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How can energy conservation not be violated in stimulated emission processes?
Fermis golden rule, derived from time-dependent perturbation theory, give the rate for a quantum system, disturbed by a weak harmonic pertubation with frequency $\omega$, to transition from a state $|...
user224659
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Can X-ray diffraction be applied to liquids, gasses or non-crystalline materials?
I learned that X-ray diffraction happens due to the periodic arrangement of atoms in a crystalline material, so can X-ray diffraction studies be done on liquids and non-crystalline materials?
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Radiation Emission due to High Temperatures?
We know that an object emits radiation at all temperatures above absolute zero.
But when an object is heated to high temperatures like the stars, Wouldn't it cause thermionic emission to take place?
...
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Does shaking an atom produce photons?
I have a vague recollection of a description of the relationship between matter and light. It went something along the lines of this: "Grab hold of a thing and ...
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Which color in emission spectrum do we really see?
For example, potassium has this emission spectrum according to google image
It is typical (and kinda necessary) for atoms to have multiple emission lines, so what determines which color we actually ...
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What is the difference between scattering and absorption/emission?
As far as I know, scattering occurs when light excites the atoms or molecules to their higher energy state(virtual state for scattering) followed by emitting photons corresponding to energy ...
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What is electromagnetic radiation (when it is not a 'wave' of EM fields or interacting locally as a photon)? [closed]
My questions are related to the question asked at Are EM radiation and EM waves the same thing?. My background is in math (my Ph.D. thesis was in geometric analysis), and I have only taken basic ...
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How is energy conserved in spontaneous emission?
I was reading through the section on spontaneous emission in Introduction to Quantum Mechanics (2nd Ed.) by Griffiths. In section 9.2.2 he explained that spontaneous emission is really a stimulated ...
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When does an oscillating charged particle emit a photon as a result of acceleration?
As far as I know a charged particle emits a photon when it undergoes acceleration.
When it comes to collisions it seems quite straightforward that a single photon is emitted with an energy related to ...
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How do we detect infinitely narrow emission / absorption lines within continuous electromagnetic spectra?
This always bothered me, especially in the case of absorption lines. for instance, if you have a blackbody emitting a continuous spectrum, and then a filter in front that only filters out one very ...
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Calculating the intensity of an emission spectrum line
I'm writing a program which generates the emission spectrum of an element with atomic number $Z$. To do this, I have used the equation:
$$\frac{1}{\lambda} = R_{\infty}Z^2\left(\frac{1}{n_1^2}-\frac{...
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Why don't absorption and emission lines cancel out in our Sun?
I was looking at this answer on why absorption lines and emission lines don't cancel out:
An experiment shining light on the material and looking at the
reflected spectrum will see absorption ...
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3
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Question on relation between resistance and photon emitting
|Hello, everyone, I have a question regarding the relation between photon emitting in terms of electricity. I asked the question in the Electrical Engineering forum but I was told that here is the ...
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Are there limits for photon energy?
Inspired by this question, I have slightly different question.
One way how photons are produced is through quantum oscillator transition from upper state $E_2$ to lower state $E_1$. The photon energy,...
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Why is the energy expressed in an electron orbital change of state electromagnetic (photon)? [closed]
As I understand it, Schrodinger's wave equation predicts the allowable energy states an electron can have under the electromagnetic forces of a given nucleus (and I assume other 'orbital' electrons). ...
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How many photons are there in free space on average
Estimates of the amount of for example "dark matter" are of interest to the cosmologists. However, I have never seen an estimate of how many "free" photons could be speeding about in the known ...
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Estimating temperature with Boltzmann relation with split emission lines
I'm trying to estimate the temperature of a plasma through the use of hydrogen lines, $H_{\alpha}$ and $H_{\beta}$ using the Boltzmann relation:
$$ \frac{ n_{2} }{ n_{1} } = \frac{ g_{2} }{ g_{1} }e^...
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What are the properties of the electromagnetic radiation from a magnetron?
There are different modes of EM radiation. A bulb emits photons in a wide range of wavelengths and without polarisation. Radio waves are polarized modulated radiation.
What is about the radiation ...
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Excited Energy levels of Hydrogen vs Solids
My question has to do with Excited Energy Levels.
I keep reading and learning that all objects/most solids emit infrared radiation.
But to emit radiation, an object's particles must first enter a ...
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