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

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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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1answer
72 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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50 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
48 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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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
24 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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1answer
38 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
61 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 could ...
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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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834 views

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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1answer
72 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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0answers
29 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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2answers
39 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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1answer
46 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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1answer
63 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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2answers
161 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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1answer
66 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
246 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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2answers
174 views

Is plant photosynthesis more efficient than solar panels?

Is photosynthesis more efficient than solar panels? If so, by how much?
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1answer
62 views

CCD's and the photoelectric effect

Do charge coupled devices as found in telescopes use the photoelectric effect if not what eles librates the electons. Also what is charge intergration in reation to CCD's.
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57 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 ...
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1answer
59 views

What causes the Fermi Tail in Photoelectric effect?

I did a Photoelectric effect experiment, with this setup (schematic): Figure 1 Scheme of the setup The kathode is made of Potassium. Light is passing through the monochromator and on the kathode. ...
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1answer
27 views

Do I need to take both particles' momentum into account in photoelectric emission? [closed]

An aluminum dust particle of mass $m=2.2*10^{-18}$ grams is floating in space ( initial velocity is zero). The particle emits electron under influence of a photon whose frequency is $8*10^{17}$ ...
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1answer
89 views

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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0answers
183 views

How does a Photocell/Photoresistor work? [closed]

I'm just curious highschooler beginning an interest in electronics and this concept of light detecting resistance component is really intriguing to me. I assume it's an application of the ...
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2answers
111 views

Photoelectric effect: current vs wavelength

In an experiment where the type of metal,intensity of light and potential difference across a battery is kept constant at 2V the results show that an increase in wavelength, obviously in turn ...
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1answer
63 views

Unusual observation in photoelectric effect simulation

I was studying a photoelectric simulation (http://phet.colorado.edu/en/simulation/photoelectric) and I observed a really unusual thing. When I held intensity and potential at a constant value and then ...
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2answers
69 views

Why 'max' in $hf=\phi+{1\over{2}}mv_\text{max}^2$?

The equation for the photoelectric effect is $$hf=\phi+{1\over{2}}mv_{\text{max}}^2$$ How does this make sense given that $hf$ describes a single photon and ${1\over{2}}mv_{\text{max}}^2$ describes ...
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3answers
161 views

where does the photon go after scattering?

My question is about photo electric but it could be applied to other daily routine phenomenon. As we know rest mass of photon is zero. When a photon strikes the ...
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2answers
813 views

Relationship between stopping potential and work function

Suppose I have a cathode with a work function of 3eV and an anode at a potential of 2V above the cathode. If a photon having 2eV of energy hits the cathode, what happens? A. An electron is emitted ...
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1answer
108 views

Photoelectric Effect, Why can't two quanta interact with an electron at the same time?

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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1answer
105 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
382 views

Can a photon survive a collision? If so, is it at rest during the process?

Background Irving Kaplan, in Article 6.7: The Compton Effect of Nuclear Physics (2nd Ed.) explains the Compton effect as follows: Compton (1923) was able to show that when a beam of ...
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1answer
134 views

Light behaves as a particle or wave in this thought experiment?

Consider a metal plate, on which a light of appropriate wavelength is incident such that it creates an interference pattern. The wavelength is chosen such that it can cause detectable photo-electric ...
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1answer
130 views

Doubt in solving question related to photoelectric effect?

Question:- When a beam of $1.06eV$ photon of intensity = $2.0 W/m^2$, falls on a platinum surface of area $1.0*10^{-4}m^2$, and work function $5.6eV$, $0.53$% of incident photons ejected photo ...
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photoelectric effect - $dN/dt$

Lets say we have a photocell which intercepts the photons of energy $E$ and power $P$. Between an anode and cathode there is a positive voltage so that we get an electric current: \begin{align} ...
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321 views

Intensity of light that produces largest current in Photoelectric Effect + Stopping Voltage Question

For the first image: For the Sodium metal, the Current produced by the cell is the highest when shined on by 196nm light - Not the highest, why is that? What determines the intensity of the light ...
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3answers
5k views

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
94 views

Photoelectric effect - shining light on a silver ball

Lets say we have a silver ball hanging on an isolator string. The work function $A_0$ of a silver and radius $r$ of the ball are known. Now we shine light of known $\lambda$ on it from all the ...
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1answer
415 views

Photoelectric effect - calculating a current in the photocell in which only $5\%$ of photons manage to cause the effect

I have been trying to solve a problem about photocell and have obtained the wrong result. Can anyone tell me where did I go wrong? So it is easier I will write down all my calculations. We have a ...
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3answers
160 views

Photoelectric effect: according to classical physics?

This is a sample test question I've encountered twice in some practice chemistry finals. I'm a little bit confused about what it's asking. You are conducting an experiment on the photoelectric ...
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1answer
101 views

Do photoelectrons move fast enough to use special relativity? (+ homework)

What are the speeds of the photoelectrons which are knocked out of the metal during photoeffect? Do i have to use special relativity? I am having trouble solving a homework using relativity. But if ...
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Experimental study of the Photoelectric effect [duplicate]

As I was reading about the experimental arrangement for photoelectric effect, I saw a diagram that puzzled my knowledge of electrodes. I found that in the experimental setup the cathode of the ...
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5answers
2k 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
86 views

Why are there multiple L-edges in X-ray photoionization?

In heavier elements, why are there multiple L-edges in photoionization? In the image below, what do $\rm{L_{I}}$, $\rm{L_{II}}$ and $\rm{L_{III}}$ stand for? In this handout, (page 141 Figure 7.13), ...
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1answer
60 views

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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1answer
70 views

Charge gained due to photoelectric effect [closed]

Here I think, one beam will knock out just one electron. So, I am not able to even understand what the question says. Please someone give a hint as to what the question asks... As source of the ...
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1answer
2k 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 $2.8\ eV$. Find the maximum kinetic energy of any photo-electrons (in Joules). I'm confused exactly how to do ...
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1answer
164 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
50 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 really isn't a color, but that's what my chart of the light spectrum says. Unless I ...