Q. The ratio of the frequencies of the long wavelength limits of Lyman and Balmer series of hydrogen spectrum is

A) 27 : 5
B) 5 : 27
C) 4 : 1
D) 1 : 4
Explanation

(a) For Lyman series
$v_{Lyman} = \frac{c}{\lambda_{\max}} = RO\left\lbrack \frac{1}{(1)^{2}} - \frac{1}{(2)^{2}} \right\rbrack = \frac{3RC}{4}$
For Balmer series
$v_{Balmer} = \frac{c}{\lambda_{\max}} = RO\left\lbrack \frac{1}{(2)^{2}} - \frac{1}{(3)^{2}} \right\rbrack = \frac{5RC}{36}$
$\therefore\frac{v_{Lyman}}{v_{Balmer}} = \frac{27}{5}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.

Want more practice?
Practice Nuclei MCQs