The concept of photoelectric effect should be explained.
Albert Einstein explained famous mysterious phenomenon, called the photoelectric effect. In the photoelectric effect, electrons are ejected from the surface of a metal when it is exposed to the light. The incident light should be of a certain minimum frequency called the threshold frequency. The number of electrons ejected was proportional to the intensity of the light. The energies of the ejected electrons weren’t related to it. Electrons weren’t ejected below the threshold frequency.