question_answer

The electron in a hydrogen atom first jumps from the third excited state to the second excited state and subsequently to the first excited state. The ratio of the respective wavelengths, of the photons emitted in this process is : [JEE Main 12-4-2019 Afternoon]

A) 9/7

B) 7/5

C) 27/5

D) 20/7

Correct Answer: D

Solution :

[d]