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Mechanically, what does light intensity mean?

  1. Dec 23, 2015 #1
    I am not sure what intensity actually looks like and means for light. Does this mean that ex red photon, that there are more than one photon that are superimposed on each other hitting the same spot?
  2. jcsd
  3. Dec 24, 2015 #2
    Intensity is defined as Power / Area. Therefore you can simply think of intensity as being correlated to the number of photons hitting at a surface in a given time period. Also, it depends on the frequency of the photons, since higher frequency photons are more energetic. I can't think of a reason the photons would be superimposed on one another.
  4. Dec 24, 2015 #3


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    In classical wave picture, higher intensity implies a larger amplitude of the wave. In photon picture, it means more photons per unit time.

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