Question

Ratio of Einstein’s coefficients for absorption and stimulated emission, B12 and B21 is
A. 2
B. 1
C. 0.5
D. none of the above​

Answer 1

Answer:

c is correct I am lohitha

Answer 2

The ratio of Einstein's coefficients for absorption 'B12' and stimulated emission 'B21' is 1.

• Einstein's theory of absorption and emission is based on Planck's theory of radiation.
• At thermal equilibrium rate of absorption and rate of emission is always equal according to Boltzmann's distribution law.

• B12 is the probability of absorption transition per unit time.
• B21 is the probability of stimulated emission of radiation per unit time.
• From Boltzmann distribution law and Planck's theory of radiation, we get B12 = B21.
• Then, their ratio is 1.