Physics-
General
Easy
Question
A photon of 
Joules is absorbed by a material under special circumstances. The correct statement is
- Electrons of the atom of absorbed material will go the higher energy states
- Electron and positron pair will be created
- Only positron will be produced
- Photoelectric effect will occur and electron will be produced
The correct answer is: Electron and positron pair will be created
For electron and positron pair production, minimum energy is 1.02 MeV.
Energy of photon is given 1.7 ´ 10-3 J 
= 1.06 MeV.
Since energy of photon is greater than 1.02 MeV,
So electron, positron pair will be created.
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