B About electrons and the photoelectric effect

rareEarthminerals
I understand that electrons can be released from a material, such as metal, through the photoelectric effect. I also understand that some of them might "re-attach" themselves to the metal. For practical uses, it sounds like the electrons would be re-captured in some way, but for the electrons that are cast away - how far away can they go? Do they just float around in space forever? Or can they attach to other things? If they do not attach to something else, can they "die," or are they converted to different forms of energy eventually?

I am very much a beginner to physics, but I can't seem to find an explanation of this anywhere so would appreciate any help. Thank you!
 
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rareEarthminerals said:
I understand that electrons can be released from a material, such as metal, through the photoelectric effect. I also understand that some of them might "re-attach" themselves to the metal. For practical uses, it sounds like the electrons would be re-captured in some way, but for the electrons that are cast away - how far away can they go? Do they just float around in space forever? Or can they attach to other things? If they do not attach to something else, can they "die," or are they converted to different forms of energy eventually?

I am very much a beginner to physics, but I can't seem to find an explanation of this anywhere so would appreciate any help. Thank you!

You need to figure out the rest of the setup.

The standard photoelectric effect experiment has an anode to attract the emitted photoelectrons. So these electrons just simply do not "float" endlessly. It is how we could detect the photocurrent and thus, say that there is emitted electrons.

If there is no anode source (such as in a photoemission experiment), then the electrons will simply go along the direction that they were emitted until they bump into something, usually the walls of the vacuum vessel. Most of the electrons are emitted with a net energy, so they already have a momentum in a particular direction. So again, they simply do not meander endlessly.

Zz.
 
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rareEarthminerals said:
for the electrons that are cast away - how far away can they go?
That very much depends on the frequency provided by the source. The higher the frequency of the wave emitted, the more momentum the photo-electrons will have and thus will travel a longer distance (provided that it has not bumped into anything) than a photo-electron being emitted by a wave with the threshold frequency.
 
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. Towards the end of the first lecture for the Qiskit Global Summer School 2025, Foundations of Quantum Mechanics, Olivia Lanes (Global Lead, Content and Education IBM) stated... Source: https://www.physicsforums.com/insights/quantum-entanglement-is-a-kinematic-fact-not-a-dynamical-effect/ by @RUTA
If we release an electron around a positively charged sphere, the initial state of electron is a linear combination of Hydrogen-like states. According to quantum mechanics, evolution of time would not change this initial state because the potential is time independent. However, classically we expect the electron to collide with the sphere. So, it seems that the quantum and classics predict different behaviours!
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