Suppose we take 2 rays of light with 10 photons each as an example. Let one of the rays be of a higher frequency than the other. We have learnt that intensity of light is the energy passing through a unit area in unit time. Also higher frequency of a wave corresponds to higher energy. Does this mean that though both the rays have same no. of photons the one with higher frequency has more intensity? I am a bit confused about the idea. Plz help.
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You are mixing the intensity definition of wave picture with particles one.
In layman's terms, when we consider particle picture of EM radiation, we define intensity as no. of photons per unit area of incidence per unit time, (since we consider energy is quantized).
To make it more understandable,
In Particle picture, one photon interacts with 1 electron irrespective of the energy it carries, hence more energy means no additional ejected electrons and intensity remains the same. (Experimentally this has been verified to be right).
In wave picture, the entire wave interacts with all the electron simultaneously, hence more energy means more ejected electrons and intensity also increases. (Experimentally this has been verified to be wrong).
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intensity means, usually, the number of photons per second. the shorter the wavelength of any single photon, the more energy it contains. so a single short-wavelength photon can do more work than a long-wavelength photon, but it is not more "intense". – niels nielsen Dec 06 '17 at 22:01