Q. In the spectrum of hydrogen, the ratio of the longest wavelength in the Lyman series to the longest wavelength in the Balmer series is :
A) $\frac{5}{27}$
B) $\frac{4}{9}$
C) $\frac{9}{4}$
D) $\frac{27}{5}$
Explanation
[Solution] $\lambda_L = \frac{4}{3R}$ (2→1), $\lambda_B = \frac{36}{5R}$ (3→2); ratio = $\frac{4}{3} \times \frac{5}{36} = \frac{5}{27}$. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.