GENERAL KNOWLEDGE

Detailed explanation-1: -Albert Einstein was awarded Nobel Prize in 1921 for discovering the photoelectric effect.

Detailed explanation-2: -Albert Einstein received his Nobel Prize in Physics in 1921 for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect. When light shines on a metal, electrons can be ejected from the surface of the metal in a phenomenon known as the photoelectric effect.

Detailed explanation-3: -Albert Einstein therefore received his Nobel Prize for 1921 one year later, in 1922.

Detailed explanation-4: -The Nobel citation reads that Einstein is honoured for “services to theoretical physics, and especially for his discovery of the law of the photoelectric effect".

Detailed explanation-5: -Since light is bundled up into photons, Einstein theorized that when a photon falls on the surface of a metal, the entire photon’s energy is transferred to the electron. A part of this energy is used to remove the electron from the metal atom’s grasp and the rest is given to the ejected electron as kinetic energy.