Calcultat the frequency of the spectral line emitted when the elercton in ` n= 3` in ` H-`atom de-excites to ground state ` R_H = 109737 cm^(-1)`.

Explanation

We know ,
` 1/( lambda ) = R_H [ 1/n_1^2 - 1/n_2^2]`
` :. c/(lambda ) = v = R _H . C [ 1/n_1^2 - 1/n_2^2]`
` = 109737 xx 3. xx 10^(10) [ 1/1^2 - 1/3^2]`
` = 2 . 92 xx 10^(15) sec ^(-1)`.