Photoelectric effect supports quantum nature of light because

Light is quantized when absorbed in photo electric effect i.e. any radiation is not given out completely but released in packets. This packet of light is called Quanta and has energy equal to:

where h is plank’s constant and ν is the frequency.


Hence, energy of photon depends upon the frequency.


Now by the photoelectric equation


hv = K+


K=kinetic energy of electron.


=work function. ( =


hv =energy of photon.


The minimum frequency (is required to make electron emit and the maximum kinetic energy is also dependent on the frequency (v) of photon falling on the surface.


And if the light of suitable frequency which is greater than the minimum frequency (falls on the metal surface, it surely emits photoelectron whether it is faintly illuminated or not)


By wave nature, photoelectrons energy depends on its intensity not frequency. By this, not a particular electron but all the electrons will get equal energy at any instant. Hence, electric charge of the photoelectrons is not quantized.

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