Question

Write any two types of electron emission.

Answer 1

Thermionic emission : - In this type of emission the electron is achieved by heating the electrode. Due to heating the electrons get enough energy that they emit from the surface of that material.

Photoelectric emission : - Electron emission from metallic surface by the application of light is known as photoelectric emission. When a beam of light strikes the surface of cathode normally made of potassium, Sodium the energy of photon of light is transfer to the free electrons of cathode. If the energy of incident photon is greater than the free electrons of the metal then the emission of electron from the metal take place.