Question

Under normal condition or thermal equilibrium condition.......
(a) N2 >> N1
(b) N1 > > N2
(c) N1 = N2
(d) none of these​

Answer 1

Under normal condition or thermal equilibrium condition N1 = N2.

Option (c) is correct.

Explanation:

• The atoms jump from higher energy levels to lower energy levels and emit electromagnetic radiations.
• This is known as spontaneous emission and is represented by E2 > E1.
• On the other hand, at thermal equilibrium the emission is spontaneous and the atoms release energy at different energy levels.
• The population distribution of atoms at thermal equilibrium can be represented by the following equation N2 = N1