Question

What is the shortest wavelength present in the Paschen series of spectral lines?

Answer 1

Rydberg’s formula is given as

$hc/\lambda =21.76\times {10}^{-19}(1/n_1^2-1/n_2^2)$

$h=6.6\times {10}^{-34}$ is the plank's constant.

$c=3\times {10}^8$ is speed of life.

The shortest wavelength present in the Paschen series of the spectral lines is given for values $n_1=3$ and $n_2=\infty$.

From the above values,

$\lambda =819nm$