Mechanics of the photoelectric effect

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SUMMARY

The discussion centers on the mechanics of the photoelectric effect, specifically addressing the relationship between light frequency and the number of ejected electrons. When the frequency of light is increased while maintaining constant intensity, the number of ejected electrons decreases due to the higher energy of individual photons. This phenomenon occurs because, to keep the power constant, fewer high-energy photons are available to impact the metal surface. Thus, while the kinetic energy of the ejected electrons increases, the total number of electrons decreases.

PREREQUISITES
  • Understanding of the photoelectric effect
  • Knowledge of photon energy and frequency relationship
  • Familiarity with concepts of light intensity and power
  • Basic principles of electron behavior in metals
NEXT STEPS
  • Research the equation E=hf to understand photon energy
  • Explore the concept of threshold frequency in the photoelectric effect
  • Learn about the implications of light intensity on photon count
  • Investigate experimental setups for measuring photoelectric effect outcomes
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Physics students, educators, and researchers interested in quantum mechanics and the behavior of light-matter interactions will benefit from this discussion.

D.Freya
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Given an experiment of the photoelectric effect, if we keep the intensity of the shining light source constant, by increasing the frequency of the light, the number of ejected electrons from the metal surface "decreases". I understand that increasing frequency (assuming it is already higher than the threshold) will eject electrons at higher kinetic energies, thus resulting in a higher final voltage. But I am confused as to why the number of ejected electrons decreases with higher frequencies?? I don't see the relationship.

Side note: I thought about how wavelength is inversely proportional to frequency and so higher frequency --> lower wavelength and the possibility of a photon impacting an electron decreases. I also thought about how the the increased final voltage would build up faster, preventing additional electrons from being ejected. Both answers are apparently incorrect.
 
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Higher frequency photons have more energy, so in order to keep the intensity (power) the same you have to have fewer of these higher energy photons.
 
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