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Questions tagged [photoelectric-effect]

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

Frequency dependence

It can be shown experimentally that the maximum energy with which electrons are ejected varies in direct, linear proportion to frequency of the light falling on the metal (that is inversely with the wavelength).

Intensity dependence

It can be shown experimentally that for a fixed wavelength the rate with which electrons are ejected varies in direct linear proportion to the intensity of the light.

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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 explanation. [...] In fact we shall see that the photoelectric…
user4552
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How can a photon collide with an electron?

Whenever I study the photoelectric effect and the Compton effect, I have always had a question about how a photon can possibly collide with an electron given their unmeasureably small size. Every textbook I've read says that the photo-electrons are…
DH K
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Is plant photosynthesis more efficient than solar panels?

Is photosynthesis more efficient than solar panels? If so, by how much?
Chris Laforet
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Photoelectricity in daily life

Photons strike metals innumerable times in our day-to-day experience.Then, why photoelectrons do not come out of metal surface and cause current?
user182687
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Electron leaving the atom

From the photoelectric effect, we know that a photon can kick an electron outside the atom if it has the right amount of energy ($E_{\gamma} \geq W_0$). On the other hand, pair production tells us that a photon can annihilate to form an electron and…
Nour Aldein
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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 scattered at some angle, and the electron is released…
Bruno Stonek
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What's the difference between the work function and ionisation energy?

In a particular textbook, the work function of a metal (in the context of the photoelectric effect) is defined as: the minimum amount of energy necessary to remove a free electron from the surface of the metal This sounds similar to ionisation…
Huey
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Photoelectric effect – Why does one electron absorb only 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 another to make up the required amount – it was as…
TheQuantumMan
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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 increases then their velocity also increases, if…
rishabh gupta
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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 atomic properties of the metal (atomic number,…
David Z
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Photoelectric effect, low frequency light

Let's say we have a emitter, emitting light that has frequency f, less than the threshold frequency of a metal. If you leave light shining onto that metal, for long enough, does the energy of the individual photons accumulate, on the electrons, so…
Anonymous
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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 know that at saturation current all the…
humble
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What is different in the morning sunlight so it doesn't produce as much electricity as at noon?

Consider I have a solar panel setup as in the above picture. The top sketch is sketching sun rays in the early morning around 6 AM in a clear bright sky. The bottom sketch is sketching the sun ray hitting the solar panel at around 8 AM. I installed…
AirCraft Lover
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Why do electrons move towards anode in the Photoelectric effect experiment?

Consider a Photoelectric effect experiment apparatus as shown in Figure 11.1 The variation of photocurrent with the voltage applied across $\mathrm{A}$ and $\mathrm{C}$ is as shown in Figure 11.3. My question – Why is the current non-zero even if…
Apoorv Potnis
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Is photoelectric effect a surface phenomenon?

I got this question on a test and the answer key states that the answer is 'Yes'. According to what I understand electrons are emmitted with different kinetic energies based upon their depth from the metal surface i.e. an electron would come out…
Meet Shah
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