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

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Continuum Wave Function for the electron

I'm trying to understand certain processes like the photoelectric effect and Bremsstrahlung. In Bremsstrahlung I need to use the wave function of an electron coming from the continuum, and there is ...
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79 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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131 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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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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4k views

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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102 views

Photoelectric Effect - How are the electrons regained?

When the photons with enough energy impinge on a photocathode, it emits electrons. Does this mean that the solid will lose all its electron at one point? If not, how are electrons restored?
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203 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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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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2answers
55 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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48 views

Photoelectric effect: Why does monochromatic radiation produces photoelectron with a spread of velocities?

Recall that in photoelectric effect, $V = \frac{hf}{e} - \frac{Wo}{e}$. The incident photon with frequency f produces an electron with energy eV. This should result in a single velocity, why is there ...
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How to distinguish Shake-Up Satellites from Plasmons?

I am studying XPS spectra (X-ray Photoelectron Spectroscopy) at the moment. In XPS, different processes can influence the final state energy of detected electrons. One of these processes is the ...
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909 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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50 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
57 views

Calculating wavelength in photoelectric effect

How do I know what wavelength should radiate on a material with $W = 2.46 eV$ so that electrons are emitted with a maximum velocity of $1.0$x$10^{-6}$?
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32 views

Is my representation of $\varphi$ Work function correct?

I am a middle-school so my understanding of physics may not be as solid as you professional physicists but never the less thought its worth a try to learn more. I read about photo-electric effect by ...
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22 views

Definition Of Dark Current In PhotoDetectors

What is The Definition of Dark Current In PhotoDetectore. How Can I Eliminate This Effect. I Think When Electrons Near The Conduction Band Are Excited Into It By Thermal Effect Then Dark Current Is ...
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49 views

Photoelectric effect experiment: is charging time proportional to current?

I'm not really sure what tags to add to this question, but definitely this is just an introductory physics experiment. Let me refresh you first with the basics of the photoelectric effect. We all ...
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80 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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55 views

Why do electrons eject only if the frequency of incident ray is greater than the threshold frequency? [closed]

Why do the electrons start moving even if the dim light (less intense) of a specific frequency falls on the material ?
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3answers
543 views

What are thermal energy distributions?

I am trying to understand the photoelectric-effect deeply. My teacher used the Planck's law and integrated it to deduce the Stefan-Boltzmann law. He somehow showed some quantum-physical ...
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1answer
44 views

Photoelectric Effect and Electromagnetism Voltage Problem

Whenever a book talks about the photoelectric effect, it talks about how we can use a battery to attain a $V_{stop}$. Basically, you are making the metal plate on which you don't shine light have a ...
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The probability of electron-hole pair recombination as a function of physical proximity

When we shine line of an appropriate wavelength at a metal, e.g. gold, such that there is sufficient energy to promote an electron from the valence band to the conduction band, we'll generate with ...
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1answer
108 views

Direction of Photo Electron Emission

I was looking for information on how the photo electrons are emitted when under X-ray radiation. In this ancient review paper here http://authors.library.caltech.edu/1551/1/WATpr28.pdf they state that ...
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Photoelectric effect Experiment - What's the voltage bias of the set up?

What's the bias of the setup? Forward / Reverse? I'm doing a photoelectric effect experiment.The experimental setup involves a photocell, which has an emitter (cathode) Potassium and a ...
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Is Photoelectric Effect continuous or discrete?

I don't understand how electrons and photon interact with each other when a metal surface is illuminated with light. I've read that below a certain threshold frequency or wavelength of light, no ...
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92 views

Does quantum mechanics contradict macroscopic determinism?

I am wondering whether it is true to ask whether determinism is still completely viable at macroscopic scales given that the constituent particles behave according to QM when the dimensions get small ...
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9k views

What happens to the absorbed light energy?

When light comes across with a solid material, some of it is reflected, some of it passes through and some of it is absorbed. I understand the reflection and passing through, but I don't understand ...
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169 views

why stopping potential in the photoelectric effect is negative?

I am reading an introduction article for photoelectric effect. It is said that the variable potential was tuned until no single one photoelectron can reach the electron collection plate. But if we ...
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What is the difference between photoelectric effect and Compton scattering?

What is the difference between photoelectric effect and Compton scattering? These two effects explains interaction of photon with electron. Why in photoelectric effect whole energy of photon is used ...
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156 views

What happens to a metal plate in the photoelectric effect?

In the photoelectric effect the electrons are supposed to be removed from the plate if light of appropriate wavelength hits the plate. If electrons are removed, the plate should get ionized ...
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71 views

Does the photoelectric effect require a battery or a circuit?

This is how the professor showed us the photoelectric effect: Does the photoelectric effect require: a. a battery? what happens if the battery is replaced with a wire? b. a circuit? what happens ...
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52 views

Energy loss in the photoelectric effect

If a photon hits an electron with an energy that is less than the energy required to change the energy level of an electron, what happens to the energy of the photon (is it not absorbed and just pass ...
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1answer
204 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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1answer
101 views

Is a vacuum needed in photoelectric effect?

This question was asked to me. My first thought was that electrons may ionise the air and potential difference that was applied may increase or decrease the current which should have been observed. ...
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1answer
88 views

Is the photoelectric effect a type of nuclear decay?

If the frequency of light is $f$ and if $f \ge f_t$, where $f_t$ is the threshold frequency, electrons are emitted if light is shined on a metal surface. By my understanding, the light comes in and is ...
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Why photon has a wave nature? [duplicate]

Wave theory does not account for the photon model, which was developed only to explain quantum effects like photoelectric effect. Then why do we talk about a photon's reflection and rarefaction, as ...
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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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3answers
132 views

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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1answer
35 views

Is photoelectric emission same as ionization or are they different?

According to my book the mechanism of ionization is: "If an atom absorbs enough energy so that an electron is raised to the highest energy level the electron becomes free of the atom i.e. ionization ...
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Contact electricity and photoelectric effect

Most universities provide an experiment about the photoelectric effect to determine $h$ by measuring the stop voltage against the light frequency and calculating the slope $h/e$. But mostly they also ...
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Does the photoelectric effect obey Ohm's law?

So, 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. Say we have a photoelectric apparatus that simply ...
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163 views

Electromagnetic radiation and black body radiation

I was taught today that the Electromagnetic wave Theory is unable to explain black body radiation. The example that was given to me: When a metal is heated, it emits different frequencies of light as ...
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82 views

Changing threshold frequency

Consider a metal surface which is being continuously irradiated with a light with frequency greater than the threshold frequency. After some time, all the electrons should have been emitted from the ...
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44 views

Atomic physics - photoelectric emission

I understand that when photoelectric emission occurs: $$h\nu = h\nu_o + K.E.$$ Where $\nu_o$ represents the threshold frequency. What I don't understand is what happens if the frequency is just equal ...
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138 views

What happens when work function = hf

What happens when the photon which hits a metal surface has energy equal to the work function of that surface? $$\phi = hf$$ I realise the emitted electron will have no kinetic energy after escape, ...
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1answer
127 views

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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1answer
150 views

Photoelectric Effect Problem

Say in a photoelectric experiment, we find a stopping potential of 1.85V for $\lambda=3000\overset{\circ}{A}$ and of 0.82V for $\lambda = 4000 \overset{\circ}{A}$. How can I get the Planck's ...
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2answers
1k 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
90 views

Photomagnetic effect

I just saw an article on wikipedia: http://en.wikipedia.org/wiki/Photomagnetic_effect "This article appears to contain unverifiable speculation and unjustified claims. Information must be verifiable ...