Photocurrent and frequency of incident light

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SUMMARY

The discussion centers on the relationship between photocurrent and the frequency of incident light in the photoelectric effect. It is established that once the threshold frequency is surpassed, the photocurrent remains constant despite increases in frequency. This is because while higher frequency light results in electrons with greater kinetic energy, it does not increase the number of electrons emitted, thus not affecting the current. The kinetic energy of electrons is indeed dependent on wavelength, as demonstrated by Millikan's experiments, which confirmed Einstein's relation.

PREREQUISITES
  • Understanding of the photoelectric effect
  • Familiarity with Einstein's photoelectric equation
  • Knowledge of Millikan's oil drop experiment
  • Basic principles of quantum mechanics
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  • Research the photoelectric effect and its implications in modern physics
  • Study Millikan's experiments and their significance in validating quantum theory
  • Explore the relationship between wavelength and energy in electromagnetic radiation
  • Investigate applications of the photoelectric effect in photovoltaic cells
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Physics students, educators, and researchers interested in quantum mechanics and the photoelectric effect, as well as those studying the practical applications of these principles in technology.

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Why is photocurrent in the photoelectric effect independent of the incident frequency of light after the threshold frequency? If more frequency means more kinetic energy of electrons, then doesn't that mean that there should be more electrons passing a cross-section of the metal tube per second i.e more current?
 
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Actually, the kinetic energy of the electrons is dependent on the wavelength, that is how Millikan verified Einstein's relation:

http://www.fisica.net/quantica/millikan_a_direct_photoelectric_determination_of_plancks_h.pdf

Shorter wavelength => greater energy => greater current.
 
So decreasing the wavelength does increase the current. I thought it had no effect.

I will read that link when I have the time.

Thanks a lot Jano L.!
 

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