How could you influence the number of photons emitted from a metal

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Discussion Overview

The discussion revolves around how various factors influence the number of photons emitted from a metal surface, particularly focusing on the roles of light intensity, frequency, and the work function of the metal. Participants explore theoretical implications and potential relationships between these factors.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant suggests that increasing light intensity should increase the number of emitted photons, as intensity correlates with the number of photons in light.
  • Another participant questions this assumption, highlighting that frequency may be more critical than intensity, noting that a "critical frequency" must be met for electrons to be emitted.
  • A participant elaborates on the work function, stating it represents the minimum energy required to release electrons and discusses how the distribution of electron energies affects emission at different intensities.
  • There is a suggestion that at high intensity, the number of emitted electrons could be proportional to intensity, but at low intensity, this relationship may not hold due to the distribution of electrons.
  • One participant speculates about the nature of the relationship between frequency and the number of available electrons, suggesting it may be non-proportional and dependent on energy distributions.
  • Another participant proposes a graphical representation of the relationship between intensity and current, suggesting an S-shaped curve for frequency versus current, indicating saturation effects.

Areas of Agreement / Disagreement

Participants express differing views on the relative importance of intensity versus frequency in photon emission, and the discussion remains unresolved regarding the exact nature of these relationships.

Contextual Notes

Participants mention the need for a deeper understanding of energy distributions and the implications of varying intensity and frequency, indicating that assumptions about these relationships may not be fully explored.

JDiorio
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Just wondering, how could you influence the number of photons emitted from a metal surface. I would assume that increasing the intensity of the light would cause an increase because the intensity is a measure of the amount of photons traveling in the light. But what about other factors such as frequency or even the work function of the metal. How would that affect this number of emitted photons?
 
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so I've done a little more research and I am not sure about my original hypothesis now.. I have found that the frequency at which the light is emitted is much more important then the intensity. If a "critical frequency" is not met, then no electrons will be emitted despite how intense the light it.

However, what if the intensity is changed once this critical frequency is reached. Then would there be a direct relationship between the intensity and number of emitted electrons.. or no. I believe there is a connection between the energy.. but to conclude a larger number of emitted electrons is not vaild. Any information would be great..
 


I think the following is true:
The Work Function refers only to the minimum binding energy of electrons to the surface - i.e. the minimum frequency of photons which will release a photoelectron. It's only the tip of the iceberg but proved A Einstein's point! There will be a distribution of electron energies near the surface. For very low intensity radiation with energy very near to the Work Function, some of the incident photons may not get to interact with an appropriately weakly bound electron. For a high intensity, the number of electrons produced would be proportional to intensity because there are more than enough incident photons to hit every available electron. But at low intensity, for the above reason, the current might not be proportional but related to the actual distribution of suitable electrons on the surface.

Also, as the frequency is increased above the threshold, the number of 'available' electrons will also increase non-proportionally, according to the statistics of the energy distribution of the electrons. For a better idea, you'd need to look into the actual energy distributions.
 


sophiecentaur said:
I think the following is true:
The Work Function refers only to the minimum binding energy of electrons to the surface - i.e. the minimum frequency of photons which will release a photoelectron. It's only the tip of the iceberg but proved A Einstein's point! There will be a distribution of electron energies near the surface. For very low intensity radiation with energy very near to the Work Function, some of the incident photons may not get to interact with an appropriately weakly bound electron. For a high intensity, the number of electrons produced would be proportional to intensity because there are more than enough incident photons to hit every available electron. But at low intensity, for the above reason, the current might not be proportional but related to the actual distribution of suitable electrons on the surface.

Also, as the frequency is increased above the threshold, the number of 'available' electrons will also increase non-proportionally, according to the statistics of the energy distribution of the electrons. For a better idea, you'd need to look into the actual energy distributions.

Hmm, non-proportionally concave up or concave down? (just trying to get a general feel for what happens)
 


Concave down, in the case of intensity - approaching 45degrees - one photon for one electron, eventually.
I would thing S shaped for the frequency / current - ending up horizontal (i.e. once saturation has occurred, no extra electrons will be available to come off. I pictures a sort of Fermi distribution but that's very speculative - verging on BS, I'm afraid.
 

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