Question

A photon of $1.7\times {10}^{-13}$ joule is absorbed by a material under special circumstances. The correct statement is :

• A. Electron of the atoms of absorbed material will go the higher energy states.
• B. Electron and positron pair will be created
• C. Only positron pair will be produced
• D. Photoelectric effect will occur and electron will be produced

Answer 1

The correct option is B Electron and positron pair will be created

For electron and positron pair production, minimum energy is $1.02MeV$.
Energy of photon is given: $1.7\times {10}^{-3}J=\frac{1.7\times {10}^{-13}}{1.6\times {10}^{-19}}$$=1.06MeV$.
Since energy of photon is greater than 1.02 MeV, electron positron pair will be created.