Question

A hydrogen atom in the ground state is excited by radiations of wavelength $975A$${}^o$. The energy state to which the atom is excited, is

• A. $1$
• B. $2$
• C. $3$
• D. $4$

Answer 1

The correct option is D $4$

$\lambda =97.5nm$

Let it jumped to energy state $n$.

$\frac{1}{975\times {10}^{-10}}=1.1\times {10}^7\times 1^2[\frac{1}{1^2}-\frac{1}{n^2}]$

$0.935=1-\frac{1}{n^2}$

$n=4$