Question

Ratio of longest wavelengths corresponding to Lyman and Balmer series in hydrogen spectrum is:-

• A. $\frac{9}{31}$
• B. $\frac{5}{27}$
• C. $\frac{3}{23}$
• D. $\frac{7}{29}$

Answer 1

Answer: (B)

${\left(\frac{{\lambda }_{\text{Lyman }}}{{\lambda }_{\text{Balmer }}}\right)}_{\max }=\frac{\left(\frac{1}{2^2}-\frac{1}{3^2}\right)}{\left(\frac{1}{1^2}-\frac{1}{2^2}\right)}$
$=\frac{5/36}{3/4}=\frac{5}{27}$