Question

19. Show that it is impossible for a photon to give up all its energ
and momentum to a free electron. This is the reason why th
photoelectric effect can take place only when photons strik
bound electrons. [A + CO]​

Answer 1

Answer:

A photoelectric effect is the absorption of a gamma quantum by an electron, in which the gamma quantum gives up almost its entire energy to the electron. Absorption by a free electron is impossible, as the law of momentum conservation is not satisfied.