Number of photons in photoelectric effect

AI Thread Summary
The intensity of light correlates with the number of photons, meaning higher intensity results in more photons per second. Each photon can release a maximum of one photoelectron, establishing a direct relationship between photon count and photoelectric effect. However, the number of photons is subject to statistical fluctuations, known as "Shot Noise," which can affect measurements. While a consistent average can be observed, actual photon counts may vary from second to second. Understanding these concepts is crucial in fields like photometry and astrophotography.
cbram
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Does the intensity of light mean increase no. of photons?
 
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cbram said:
Does the intensity of light mean increase no. of photons?
For a given frequency of photons it does. A maximum of one photoelectron for each arriving photon.
 
Then for instance if the light carries 21 photons per second then the next second also should carry the same amount of photons
 
cbram said:
Then for instance if the light carries 21 photons per second then the next second also should carry the same amount of photons


The equivalence is only there for statistically large numbers. You would not get 21 every second.
 
Thanks for the information
 
cbram said:
Then for instance if the light carries 21 photons per second then the next second also should carry the same amount of photons

Oh, if only! The statistical fluctuation in photons per unit of time is known as "Shot Noise" and is a major source of noise in photometry, astrophotography, and other areas.
 
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