Photoelectric Effect -Laws of Photoelectric Emission


(1) The rate of emission of photoelectrons from the surface of a metal is directly proportional to the intensity of the incident light falling on the surface.

(ii) The maximum kinetic energy of the emitted photoelectrons is independent of the intensity of the incident light.

(iii) The maximum kinetic energy of the photoelectrons increases linearly with increase in the frequency of the incident light.

(iv) If the frequency of the incident light is below a certain lowest value, then no photoelectron is emitted from the metal. This lowest frequency (threshold frequency) is different for different metals.

(v) As soon as the light is incident on the surface of the metal, the photoelectrons are emitted instantly, that is, there is no time-lag between incidence of light and emission of electrons.

%d bloggers like this: