Question:
If $\lambda_{1}$ and $\lambda_{2}$ are the wavelengths of the third member of Lyman and first member of the Paschen series respectively, then the value of $\lambda_{1}: \lambda_{2}$ is:
Correct Option: , 3
Solution:
$\frac{1}{\lambda_{1}}=\mathrm{R}\left[\frac{1}{1^{2}}-\frac{1}{4^{2}}\right]$
$\frac{1}{\lambda_{2}}=\mathrm{R}\left[\frac{1}{3^{2}}-\frac{1}{4^{2}}\right]$
$\frac{\lambda_{1}}{\lambda_{2}}=\frac{\left[\frac{1}{9}-\frac{1}{16}\right]}{\left[1-\frac{1}{16}\right]}=\frac{7}{9 \times 15}$
$\frac{\lambda_{1}}{\lambda_{2}}=\frac{7}{135}$
Click here to get exam-ready with eSaral
For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.