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

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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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1answer
46 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
86 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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3answers
26 views

Photoelectric effect. current and frequency relationship [closed]

Does increasing the frequency of photons increase the photo-current? (keeping the light intensity constant) Is this graph correct?
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1answer
38 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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1answer
46 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
31 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
68 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
52 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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2answers
219 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
350 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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68 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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1answer
48 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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1answer
84 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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3answers
84 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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3answers
3k 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
125 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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2answers
5k 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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1answer
119 views

Time to emit electrons

Explaining the photoelectric effect, our teacher told us that back in that time, they calculated the time that an electron would take to be emitted from an atom if the energy got to the atom in a ...
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1answer
106 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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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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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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0answers
66 views

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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219 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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1answer
295 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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1answer
77 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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3answers
143 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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2answers
1k views

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 ...
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1answer
92 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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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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39 views

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 ...
4
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1answer
80 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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48 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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757 views

Schematic design of the apparatus (photoelectric effect)

I think I understand the basic idea of photoelectric effect but there are two things in the schematic diagram of the apparatus for the investigation of the photoelectric effect which I do not ...
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1answer
62 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
42 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 ...
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1answer
141 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
78 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? I missed out on the days in my ...
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2answers
371 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
218 views

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 ...
3
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1answer
243 views

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 ...
2
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1answer
99 views

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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1answer
108 views

How does the specific frequency of EM Radiation relate to displacing electrons from their orbits?

I've only a general grasp on how all this works, so it could be I'm asking this poorly or misunderstanding what happens. With that said: The energy of EM radiation is a function of its frequency. ...
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1answer
64 views

Assuming collision , are there fundamental forces associated with absorbtion?

I just learned that strong and weak nuclear forces relate to decay/emission. I know absorbtion depends on Energy levels(QM) and heat(thermodynamics , kinetic energy , entropy) and E = gamma mc^2 ( ...
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1answer
265 views

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 ...
2
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1answer
1k views

Meaning of the first and second laws of the photoelectric effect

I was reading the introduction to quantum mechanics in my physics book and it begins with a discussion of the photoelectric effect and energy quantas. The first law, the one that says that the ...
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5answers
175 views

Photoelectric effect without light rays

For electromagnetic waves we have the photon association, one imagines light as particles "flying around". What is the analogy for a constant electrical field, one which doesn't change in time ...
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1answer
167 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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121 views

An electron is subjected to an electromagnetic field using the canonical equations solve

So I was given the following vector field: $\vec{A}(t)=\{A_{0x}cos(\omega t + \phi_x), A_{0y}cos(\omega t + \phi_y), A_{0z}cos(\omega t + \phi_z)\}$ Where the amplitudes $A_{0i}$ and phase shifts ...