Question

A substance absorbs electromagnetic radiations of wavelength 12.3 nm and then emits another electromagnetic radiations of wavelength 24.6 nm . If ratio of number of photons absorbed to number of photons emitted is `2:1` then ratio of energy absorbed to energy emitted will be :
A. `2:1`
B. `1:1`
C. `4:1`
D. `1:4`

Answer 1

Correct Answer - C
`(E_("absorbed")=n_(ab)xx1240/12.3)/(E_("emitted")=n_(em) xx1240/24.6)`
`=2/1xx24.6/12.3=49.2/12.3`