The observed behavior in which light falling on certain metals can eject electrons from the surface.

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How to increase the frequency of light

If we want to increase the energy of the emitted photoelectrons (in P.E) then we should increase the energy of the photons which are related to the frequency of the light, so how is the frequency of ...
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1answer
377 views

How is the Photoelectric Effect affected by Blue-Shifting

I was thinking about the Photoelectric Effect and Blue-Shifting when I came up with a thought experiment that I couldn't think of an answer for. The thought experiment is as follows: A metal plate is ...
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570 views

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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1answer
147 views

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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1answer
23 views

What determines photoelectric yield

Is there any difference between the photoelectric yield of different metals apart from the threshold wavelength? To be more clear: Will metals with the same work function emit the same amount of ...
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3answers
100 views

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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1answer
35 views

Photoelectric effect on charged plate

As far as I know, to observe the photoelectric effect, one has to expose a metal surface to high-energy radiation. But what happens if the surface has a surplus of electrons? What is the energy needed ...
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2answers
31 views

Photoelectric effect and wave particle duality

In a vacuum, if electrons are accelerated by a certain voltage, giving the electrons a specific de Broglie wavelength and were incident on a piece of metal, providing the wavelength was roughly the ...
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2answers
61 views

Dependence of saturation current in photoelectric tube on the time taken by the electron to reach the opposite plate?

The kinetic energy of an electron in a photoelectric tube increases with increase in the applied voltage across the plates of the tube, thus the velocity of the electrons also increases. Accordingly ...
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1answer
243 views

Relationship Between Stopping Voltage and Photocurrent

Online, I found a graph of photocurrent vs. stopping voltage: And I can’t figure out how photocurrent and stopping voltage have such a relationship. Stopping voltage is proportional to maximum KE ...
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1answer
44 views

Is the photoelectric effect 'Ionising Radiation'?

According to the definition on Wikipedia, ionising radiation is radiation which has sufficient energy to remove an electron from an atom. So a high energy gamma ray is definitely ionising, but visible ...
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2answers
52 views

Wave-like description of Compton scattering and photoelectric effect

I have found in the wikipedia page for QFT the following statement: ... Although the photoelectric effect and Compton scattering strongly suggest the existence of the photon, it is now understood ...
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0answers
43 views

Why call it a particle and not a wave pulse?

My physics textbook says that photoelectric emission provides conclusive evidence for the particle theory of light. Apparently, since photoelectric emission only works at certain frequencies, we can ...
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3answers
93 views

How does wave-particle duality describe Photoelectric effect?

I don't know if electrons work as particles or waves or maybe both in photoelectric effect. How is Photoelectric Effect actually described by Wave-Particle Duality?
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1answer
30 views

Thermionic emission

I have a pretty basic question regarding the beam of electrons as a result of thermionic emission. In an electron gun, the emitted electrons from the cathode become incident at a point on the other ...
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1answer
54 views

Why does one use different materials for cathode and anode in the photoelectric effect experiment

All photoeletric lab experiments I have seen so far have a setup where you have different materials for cathode and anode. However this raises some experimental difficulties since you have to take ...
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2answers
60 views

Photoelectric effect: Why is the saturation current the same, as you vary the frequency of incident light but keep its intensity constant?

image courtesy of http://www.learncbse.in/ Why is the saturation current the same, as you vary the frequency of incident light but keep its intensity constant? If intensity is a measure of the ...
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4answers
1k views

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 ...
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0answers
27 views

Photoelectric effect by cosmic radiation

In photoelectric effect, energy of photons are used to remove electrons from the atoms of the metal. Generally, energy of the photon determines the photoelectric current produced. But nuclear ...
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2answers
6k views

Relation between frequency and intensity of light

I was going through a question in photoelectric effect and it was a true/false which says that the intensity of the incident light gets doubled on doubling the frequency. The answer is given as true ...
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2answers
60 views

Why does lead have a higher attenuation coefficient for 5.0 MeV than for 10.0 MeV?

I was doing some calculations on radiation, and I noticed that lead has a higher attenuation coefficient for 5.0 MeV than for 10.0 MeV, namely $1.44 \, \mathrm{cm}^{-1}$ for the former and $1.23 \, ...
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1answer
24 views

The Photoelectric Effect in passive cooling?

Information on the Photoelectric Effect: https://en.wikipedia.org/wiki/Photoelectric_effect Summary: Some metals release electrons when struck by a certain frequency of photon. What does this mean ...
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2answers
301 views

Photoelectric effect stopping potential

$q_eV_s = hf - \phi$ My question is... suppose we are testing the photoelectric effect. One plate is illuminated. We have applied the stopping potential. Suppose an electron leaves one plate with $KE ...
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1answer
52 views

Why is dark current on CCD devices pixel dependent

I'm reading about sources of noise in cameras while taking images - One of them is the dark current. That is, some electrons in the CCD device of a camera are set free due to thermal noise. Those free ...
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4answers
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Stopping potential in the photoelectric effect, collector work function

In this question I am talking about the following situation: Now, I know that the max kinetic energy of the electrons emitted is $KE_{max} = h\nu - e\phi_{em}$ where $\phi_{em}$ is the work ...
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1answer
41 views

How is work function related to oxidation?

Low work function metals, such as Li and K, oxidize in ambient conditions, whereas high work function metals such as Au do not oxidize. In chemistry there's activation energy and reaction rate ...
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1answer
356 views

Is the current vs. frequency graph hyperbolic for the photoelectric effect?

Concerning the photoelectric effect: When the intensity and applied voltage are both constant, then the current is inversely proportional to frequency $f$ (above threshold frequency). If we increase ...
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0answers
32 views

Photon spin and photo electric effect

If a photon with spin angular momentum $+1$ with sufficient energy strikes an electron with spin $+1/2$, emission will take place. As angular momentum can't be conserved, what will happen?
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6 views

Solar cell using graphite

I recently heard that single graphite layer is developed so as to produce solar electricity. Is that possible. If so, then how is that process takes place?
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1answer
35 views

Number of photoelectrons vs Frequency

This is the graph plotted between photocurrent (proportional to number of photoelectrons) and potential applied with different frequencies. As it can be seen, the number of photoelectrons released ...
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3answers
52 views

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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2answers
89 views

Is their real difference between photoelectric and thermo ionic current?

All books say only a single photon can remove an electron at a time. But we see that during thermal emissions electrons are removed by heat waves which are actually infrared rays. These infrared rays ...
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1answer
185 views

What is the difference between the photoelectric effect and secondary emission?

What is the difference between photoelectric effect and secondary emission in photo multiplier tubes? In other words, why the difference between the energy of the incident photon and the work function ...
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6answers
13k views

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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1answer
43 views

Why work function is not identical to first ionization energy?

From Wikipedia: The ionization energy (IE) is qualitatively defined as the amount of energy required to remove the most loosely bound electron of an isolated gaseous atom to form a cation. ...
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2answers
57 views

Compton effect in photo-electric?

In photo-electric effect Einstein said that photons incidents on material and gives their energy which will gives kinetic energy to electrons. But i also want to know that why Compton's effect not ...
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0answers
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How can I calculate the bipartition angle for photoelectrons produced by photoelectric effect?

I'm taking a course in radiation physics and I'm studying the photoelectric effect. In the notes that he gave us my professor states that half of the emitted electrons are emitted forward with an ...
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2answers
158 views

Super massive Black Hole and photon reduction [closed]

This is a picture of 2 galaxies taken from The Hubble. The arrow shows a smaller galaxy's black hole starving of the usual stars because of the binary rotation about the bigger galaxy that is pulling ...
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2answers
82 views

What is basic difference between photoelectric effect and Compton effect?

What is basic difference between photoelectric effect and Compton effect? In both case a photon hits a loosely bound electron So whats the difference? We get current in photoelectric effect but not in ...
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1answer
321 views

Why don't metals disintergrate in light?

I've been learning about photoelectricity. An electron can gain the energy from a single photon, and if that energy is greater than the work function of the metal the electron can leave the metal. ...
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1answer
606 views

How is a CCD able to collect images in drastically different lighting conditions?

I have read the basics of how a digital camera works. As much as I have understood, the digital cameras have a device called a CCD on which photons coming from the lens are incident. The CCD then ...
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1answer
50 views

Has time lag been calculated?

Books says time lag in which an electron leave atom, in photoelectric effect, is negligible. Is this negligible value been calculated?
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24 views

How to measure the maximum kinetic energy of electrons emitted due to photoelectric effect?

From Einstein's photoelectric equation, $$hf = \phi + k.e_{\text{max}}$$ where $\phi$ is the work function of the metal. My question is : how to experimentally determine the kinetic energy of ...
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1answer
41 views

Why is there a longer time lag if light behaves as a wave?

In this problem: According to a model based on the electromagnetic theory of light, the electron absorbs all the energy that is incident on the surface within a distance of $5.0\times 10^{-11}\ ...
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2answers
113 views

Can one photon emit two electrons?

My question refers to the photoelectric effect. I have heard that it is possible, that for one photon, two electrons leave the irradiated metal. Is this correct and by which process can this be ...
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1answer
49 views

So why are photoelectric panels flat? (Part II)

In this post So why are photoelectric panels flat?, I've asked if we could use flat photoelectric panels with hemispheric cells. Most of the answers seemed to say it would not work. Anyway, I'm ...
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4answers
1k views

So why are photoelectric panels flat?

In this post Why not use our own light production to produce new energy instead of wasting it?, I naively asked if it was possible to also recycle our own lightning at night. someone, in his answer, ...
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2answers
98 views

Why doesn't silicon emit light? [closed]

Why doesn't silicon re-emit light when light falls on it? Or if it emits light then why we can't see it?Hence it has valence electrons.
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0answers
27 views

Extraction efficiency in photoeffect

I am looking at the extraction efficiency of the photoeffect (how many electrons end up in vacuum per photon). I have read in this forum that 1e-5 or less electrons make it outside of metal. Reason is ...
2
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0answers
47 views

Why not 2, 3, 4, or more photons can be absorbed by single electron? [duplicate]

During Photoelectric effect and other such phenomenon, when light is made to fall on metal surface, single photon is absorbed by the single electron present in metal atom. Why not 2, 3, 4, or more ...