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

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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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1answer
9 views

Dissolving photoconductor (TiOPc) from Laser Printer drum possible?

When I was thinking of a Lab-On-a Chip Application which combines a lensless microscope and an optical tweezers I saw the ...
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5answers
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In famous Einsteins Photoelectric effect, Why does intensity of light doesn't raise the kinetic energy of the emitting 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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1answer
181 views

How to calculate the photoelectric effect with photon efficiency?

I am not sure exactly where to go with this problem. The problem states: "A $1.3 \, \mathrm{mW}$ laser ($\lambda = 545 \, \mathrm{nm}$) shines on a cesium photocathode ($\phi = 1.95 \, \mathrm{eV}$). ...
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1answer
71 views

Is the photon's wave function the same as an electromagnetic wave(light)? [duplicate]

The first that i have been taught in Quantum Mechanics is the photoelectric phenomenon. Without analyzing it, it concludes that when we shine light at the circuit(roughly speaking), the work required ...
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2answers
171 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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2answers
34 views

Would an ordinary or fluorescent lightbulb generate electricity when exposed to light?

I was wondering whether the physic laws or the nature in which lightbulbs are constructed would allow for lightbulb to generate electricity when subjected to strong (intensive and concentrated) ...
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1answer
122 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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1answer
293 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 current. I ...
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1answer
13 views

How to calculate the potential of a photocell?

My guess is that because the wire is connected to a single point on the plate, we can treat it as a point charge and use the formula: $$V = k\frac{k(\pm q)}{|r|}$$ But I think there are different ...
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1answer
28 views

Why don't electrons dislodge with higher intensity?

I understand that photo-electrons are not produced with increased intensity because frequency is what matters, however could someone give me a good intuition of why this is the case? What exactly do ...
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0answers
15 views

How does the maximum kinetic energy of an ejected electron affect what happen to it after being ejected? [duplicate]

So I just learned: $$K_{max} = hf - \phi$$($\phi$ for ionization energy) I wonder what will happen if $K_max$ is zero. Will it be attracted back to the ionized atom it has come from since it doesn't ...
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1answer
11 views

Will ionization energy be affected by screening effect?

It would be logical to think that the more electrons are ejected from an atom, the harder it is to eject more. I just learned about photoelectric effect experiment. The book is kinda telling me the ...
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2answers
90 views

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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1answer
37 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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3answers
2k views

Why do electrons in an atom 'fall' back to the ground state?

Why, after absorbing a photon does an atom's electron 'fall' back to its ground state (what causes it to immediately lose its absorbed energy)?
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1answer
54 views

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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6answers
4k views

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 ...
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1answer
4k views

Finding the maximum kinetic energy of any photoelectrons?

An incident photon, $f=5.5\times 10^{14}\ Hz$, hits a metal with a work function of $2.8\ eV$. How do I find the maximum kinetic energy of any photo-electrons? I'm confused exactly how to do this, ...
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1answer
251 views

Color of a Metal's Threshold Wavelength?

How do I find the color of the threshold wavelength if the metal has a threshold wavelength of $\mathrm{6.5\times 10^{-7}m}$? I know that converts down to $\mathrm{650\ nm}$, but can I still use the ...
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1answer
63 views

Color of an incident photon?

If the incident light at 360nm causes photoemission of electrons, wouldn't the color be ultraviolet? I know that it isn't a visible color, but that's what my chart of the light spectrum says. Unless ...
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1answer
118 views

Confused about the Photoelectric Effect?

If an incident photon with frequency f hits a metal with a work force of w: How do I find the color of the incident photon and the threshold frequency of the metal? What equations are necessary to ...
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1answer
38 views

Quantum efficiency of Photoelectric effect

What is the typically measured quantum efficiency of photoelectric effect experiments involving ultra violet photons incident upon common metals like copper or aluminum. In case I'm not being clear, ...
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1answer
46 views

What if I double the frequency of incident light in photoelectric effect?

The photoelectric effect occurs when the frequency of incident radiation is above a threshold frequency. If we double this incident frequency, what effect will it have on the experiment? Also what ...
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2answers
1k 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
62 views

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 ...
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1answer
65 views

Why isn't this calculation of the energy of a light wave correct? [closed]

I'm trying to calculate the energy $J(T)$ that monochromatic light wave with electric field strength $E(T)$ supplies to unit electric charge over period of time $T$: $J(T)=\int\limits ...
3
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1answer
44 views

what is the velocity distribution of photoelectrons in photoelectric effect?

I know that when light is incident on certain metallic surfaces, electrons are emitted from the surface. And I know that the maximum velocity can be calculated. But why does the textbooks use 'maximum ...
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0answers
34 views

Electrons in a gas discharge tube

I'm having some difficulty understanding regarding electrons in gas discharge tubes. My understanding is the following: In a gas discharge tube the gas must be at low pressure in order to be ...
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0answers
25 views

Does tracing paper over a solar panel count as hard shade or soft shade?

For my Physics IA I conducted an experiment to see how shade on solar panels affects the output power. I applied and secured one layer of tracing paper over the solar panels of my solar charger at a ...
2
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1answer
144 views

Photoelectric effect – Why does one electron absorb 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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6answers
56 views

Photoelectric effect and intensity [closed]

What changes occur to the maximum kinetic energy of an emitted electron from the surface of a metal if the intensity of a laser incident to the surface is reduced
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2answers
81 views

Photoelectric effect and light coming in chunks

I was watching a lecture on introduction to quantum mechanics.While explaining the photoelectric effect,the lecturer mentioned that we must think of light as coming in chunks with each chunk having ...
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0answers
45 views

Why do we get saturation current in photoelectric effect

So apparently if you increase the number of photons emitted per second to infinity, the photocurrent will approach a limiting value called the 'saturation current' I feel like we shouldn't get a ...
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2answers
114 views

photo electric effect question

When EM radiation with fixed intensity and frequency strikes the metal plate, are the outgoing electrons at higher energy if the plate were charged to some potential than if the plate were simply ...
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2answers
36 views

Does the Photoelectric Effect cause any kind of decay?

From my understanding, the Photoelectric Effect knocks electrons off of some metal using photons. Since electrons are being thrown out of the metal, does this cause some kind of decay?
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3answers
3k views

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 frequency.I ...
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3answers
99 views

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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1answer
55 views

Saturation current vs frequency

In the photocurrent experiment, if the intensity of light is kept constant, but the frequency is slightly increased, what's the effect on the saturation current? I think saturation current should ...
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2answers
40 views

Does a time-varying intensity contribute to the photoelectric effect?

I understand the photoelectric effect demonstrates that electrons are only dislodged from a metal if incident light meets a minimum threshold frequency. I wonder if a varying intensity might also ...
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1answer
53 views

Can a solar panel work with heat?

As we know that a solar panels due to the energy of light, but can we run a solar panel with the same amount of energy provided as heat?
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1answer
60 views

Would it be efficient to run a solar panel with laser?

Would it be efficient to run a solar panel with laser? I know this question is unsual as we are using electricity powered laser to run a solar panel. Actually i am paricipating in the Google Science ...
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2answers
56 views

Photoelectric effect and variation of current?

Say a photon of frequency $\nu_1$ strikes the metal, and we have certain kinetic energy which is stopped by $V_{stop1}$. Now for frequency $\nu_2$ for same metal it will have $V_{stop2}$. Now ...
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1answer
54 views

How does a photon drive out the electrons in a solar cell?

We know that solar cells work when a photon hits the n-type the photon's energy drives free the electrons in the n-type to generate a current. But we also know that when a photon hits the atoms it ...
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6answers
9k 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 ...
0
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1answer
57 views

How can silicon have a capacity of 8 electrons in the outer shell?

I was reading an article on how solar cells work in this website- http://science.howstuffworks.com/environmental/energy/solar-cell2.htm In that website I have a doubt in the first paragraph i.e.- ...
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0answers
31 views

How much energy does a PV cell need to work?

How much energy does a $1m^2$ photovolatic/solar cell need to work? Can it work using a bunch of Laser lights? Edit: Ok so this PV cell is $1m^2$ is dimesions. The N-type has silicon doped with ...
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1answer
100 views

How do solar panels generate infinite electricity?

We know that solar cells generate electricity utilizing the energy of the photon, but how can they generate electricity forever? In a n-type terminal we have the bond of silicon and phosphorous so ...
0
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1answer
94 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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2answers
2k views