Questions tagged [photoelectric-effect]
The observed behavior in which light falling on certain metals can eject electrons from the surface.
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Can the photoelectric effect be explained without photons?
Lamb 1969 states,
A misconception which most physicists acquire in their formative years is that the photoelectric effect requires the quantization of the electromagnetic field for its explanation. ...
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Photoelectric Effect, Why can't two quanta interact with an electron at the same time? [duplicate]
I understand that assuming light is quantized implies that if a lower energy interacts with metal, it is possible that that quanta will not have enough energy to eject the electron. What prevents two ...
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Photoelectric effect – Why does one electron absorb only one photon?
When I read about the photoelectric effect, I came across this:
"The electrons could not absorb more than one photon to escape from the surface, they could not therefore absorb one quanta and then ...
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Compton scattering vs. photoelectric effect
Say a photon hits some atom.
What determines whether there will be a photoelectric effect (photon is absorbed, electron is released) or whether there will be a Compton scattering (the photon is ...
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Photoelectric Effect - Dependence of current on frequency
We all know that the amount of current flowing b/w the plates is independent of the frequency. If I were to ask why doesn't it depend then you'd probably say that it depends on the number of electrons ...
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Is energy exchange quantized?
In the photoelectric effect there is a threshold frequency that must be exceeded, to observe any electron emission, I have two questions about this.
I) Lower than threshold:
What happen with lesser ...
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Why doesn't photoelectric current increase with frequency of the incident wave?
If the frequency of the incident wave is increased, then the kinetic energy of the photoelectrons increases. If so, why doesn't the photoelectric current increase?
If the kinetic energy of electrons ...
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Why does classical physics imply every mode of vibration should have the same thermal energy?
I've just started reading about photo electric effect here, and my high school level understanding goes something like this :
1) By 1900 we had Maxwell equations and treated light as a wave.
2) But ...
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Why is the K shell electron preferred in the photo electric effect?
I have read in many books and on Internet as well that photoelectric effect is only possible when an electron is emitted from the K shell of the metal. Why not other bonded electrons?
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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 a photon collide with an electron?
Whenever I study the photoelectric effect and the Compton effect, I have always had a question about how a photon can possibly collide with an electron given their unmeasureably small size. Every ...
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What's the difference between the work function and ionisation energy?
In a particular textbook, the work function of a metal (in the context of the photoelectric effect) is defined as:
the minimum amount of energy necessary to remove a free electron from the surface ...
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Saturation current in photoelectric effect
While studying photoelectric in my school, my teacher drew a graph of current versus the potential difference across the two electrodes:
I am not able to understand why do we get saturation current. ...
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Why are photoelectrons emitted in the direction of incident photons?
In the experiments for photoelectric emission, the light is incident on one face of the emitting plate, for example the anode, when determining the stopping potential. The electrons are emitted by ...
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Expression for the (relativistic) mass of the photon [closed]
I started learning a bit ahead from an old physics book, and they were discussing the photoelectric effect and after that Planck's hypotheses and energy quantas.
The book said that the mass of a ...
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Photoelectric effect, low frequency light
Let's say we have a emitter, emitting light that has frequency f, less than the threshold frequency of a metal.
If you leave light shining onto that metal, for long enough, does the energy of the ...
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In the famous Einstein's Photoelectric effect, why does the intensity of light not raise the kinetic energy of the emitted electrons?
The work function of any metal is no doubt constant for it is related to electromagnetic attraction between electrons and protons. However on increasing the intensity of any light source the kinetic ...
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How long does it take for an excited electron to return to ground state?
During a mock Cambridge interview, one of the questions was about how small a computer could theoretically be.The way I approached it was in terms of what something must be to be considered a computer....
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Does Quantum Theory allow an Electron to take a fraction of Photon energy
In Photoelectric Effect of Theory of Spectral Lines , an electron takes the entire or none of the energy of the Photon ( it absorbs the entire quanta not its fractionS resulting in the disappearance ...
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What is the relation between photoelectric current and frequency of incident light?
I googled it a bit and found that photoelectric current is independent of frequency(of incident light). Some further look revealed that actually "saturation current" is independent of ...
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Kinetic energy of photoelectrons
I came across the following question:
A photon of energy $h\nu$ is absorbed by a free electron of a metal having work function $W<h\nu$. Then:
The electron is sure to come out
The electron is ...
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Specific electron energy gap values $E_{i+1}-E_i$ vs. photons with arbitrary energy $\hbar \omega$
The energy levels of electrons in an atom are quantized $E_i$. A photon of a specific momentum $\vec p$ and energy $$\omega=(E_{i+1}-E_i)/\hbar$$ hits an atom and gets absorbed. Okay now say the ...
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Should electrons always absorb all the energy from a photon? [duplicate]
The Wikipedia article on photoelectric effect has the following line:
Electrons can absorb energy from photons when irradiated, but they usually follow an "all or nothing" principle. All of the ...
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Photocurrent's dependence on frequency [duplicate]
Sounds like a rookie question, this, but could someone please explain to me why doesn't photocurrent increase when we increase the frequency of the incident radiation? I mean, an increase in frequency ...
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Photoelectric effect and work function
In a photoelectric effect we remove electrons from a metal using high energy photons, the work function is the minimal energy required for this effect.
My question is why doesnt the work fucntion ...
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Effect Of Frequency on Photocurrent
The situation is this.. I am performing a photoelectric effect experiment - just the usual - evacuated glass tube containing two metal electrodes connected to an external source of DC voltage (say an ...
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Why do electrons move towards anode in the Photoelectric effect experiment?
Consider a Photoelectric effect experiment apparatus as shown in Figure 11.1
The variation of photocurrent with the voltage applied across $\mathrm{A}$ and $\mathrm{C}$ is as shown in Figure 11.3.
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Does Tesla's photoelectric "solar cell" really work?
Tesla patented a device for gathering energy from light, using the photoelectric effect. (US 685,957 - Apparatus for the Utilization of Radiant Energy):
Basically just a sheet of "highly polished or ...
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Is there a way to calculate the photoelectric effect in QED via a Feynman diagram?
The photoelectric effect is the historic origin of the quantum particle description of light. From it we learn that when light is shone onto a metal single photons interact with single electrons in ...
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Does electron absorb energy? [closed]
According to my teacher, an electron is point sized and it does not absorb or release energy. Moreover, my teacher says their orbital absorbs energy rather than the electron. If that is the case, then ...
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Why doesn't saturation current in the photoelectric effect depend on the frequency of light absorbed by the metal emitter?
If current $I$ is given by $I = nAev$, where $n$ is the number of electrons per unit volume, $A$ is the area, $e$ is the charge of an electron and $v$ is the velocity of the electron, it must mean ...
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Classical (or semi-classical) interpretation of photoelectric effect?
This site says that "it has recently been proven that the photoelectric effect can be interpreted classically (or at least semi-classically) in non-particle, wavelike terms". Is anyone familiar with ...
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Why is the photopeak at a higher energy than the Compton edge?
Why does the photoeffect deposit more energy than interactions via Compton scattering?
Or the other way around: Why is the photopeak right (at a higher energy) than the Compton edge?
Compton edge (...
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Diffrence between thermionic emission and photoelectric emission
Thermionic emission involves heat energy to excite the electron and remove it. In the photoelectric effect, a beam of light is involved.
As per my understanding heat and photons, both are energy. Heat ...
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Direction of emission of Photoelectrons [duplicate]
Where does the information about the direction of the emission of the Photoelectron come from? Does it get it from the incoming Photon?
I have seen a picture on wikipedia-page of the photoelectric ...
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How bright can we make a sun jar?
A sun jar is an object that stores solar energy in a battery and then releases it during dark hours through a led.
Assume:
a $65cm^2$ solar panel
a 12h/12h light/dark cycle
insolation of $2.61kWh/m^...
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Photoelectric effect
Why the photoelectric effect is observed only for metals and not for non-metals?
Isn't it possible for the photon to release an electron from a non-metal surface?
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Photoelectric effect in a a frequency range
I know how to calculate the kinetic energy of the emitted electrons
$$KE=hf-\phi$$
And the number of the emitted electrons, but this is valid for a certain frequency
$$N=\frac{IA}{hf}=\frac{P}{hf}$...
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Why wave theory cannot explain photoelectric effect and provides evidence for particle nature of light?
I am able to understand how light can be modeled to have wave characteristics from Young's double slit experiment.
But I am unable to comprehend how we can understand light to have particle ...
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Does a single photon's energy depend on frequency? (photoelectric effect)
Essentially this question boils down to "why does the energy of light depend on frequency?".
The analogy my textbook (pg. 272 principles of chemistry A molecular Approach 3rd edition by Nivaldo J. ...
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Ejected Electrons with 0 KE?
So I was taught that:
Kinetic Energy (of electron) = Energy (of photon) - Ionization Energy
If E(photon) = IE, then KE=0 of the electron.
What does this physically/theoretically mean?
My current ...
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Photoelectric effect intensity
I understand the PE effect quite well but I'm failing to understand one thing.
Intensity is the amount of energy per second incident to a given area.
So can you can increase the intensity by either ...
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The rate of electrons emitted by the photoelectric effect
I had this question in my exam:
It asked me to compare between the effect of incresing light frequency and the effect of increasing light intensity in respect to the rate of electron emitted from the ...
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Why photon-electron energy transfer can't occur in steps or does it?
The process of exchange of energy between a photon and an electron only occur after a specific energy called work-function of the material. Thus, the energy transferred is quantised due to the fact ...
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Is photocell current equal zero at threshold frequency?
In photocell is there currant at threshold frequency $f=f_o$?
I mean $I=0$ at $f=f_o$?
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Is plant photosynthesis more efficient than solar panels?
Is photosynthesis more efficient than solar panels? If so, by how much?
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How would I calculate the work function of a metal?
In the photoelectric effect, the work function is the minimum amount of energy (per photon) needed to eject an electron from the surface of a metal. Is it possible to calculate this energy from the ...
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Does the photoelectric effect obey Ohm's law?
I've been reading about the photoelectric effect for my modern physics class, and I was confused about how Ohm's law works in relation to it. Let's say we have a photoelectric apparatus that simply ...
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Kinetic energy and Potential of a photon
How does the potential and kinetic energy of a photon relate? Do they mean the same thing?
Also how does De broglie wavelength and Potential relate?
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What if all the electrons leave a metal?
I was studying photoelectric effect. Then I thought that what will happen if all the electrons from a metal piece come out as photoelectrons by using a light source of particular frequency?
Will the ...
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