Question

Electrons are bombarded to excite hydrogen atoms and six spectral lines are observed. If $E_g$ is the ground state energy of hydrogen, the minimum energy the bombarding electrons should possess is

• A. $\frac{8E_g}{9}$
• B. $\frac{15E_g}{16}$
• C. $\frac{35E_g}{36}$
• D. $\frac{48E_g}{49}$

Answer 1

The correct option is B

$\frac{15E_g}{16}$

To obtain 6 spectral line, as electron must be excited to fourth orbit with energy $\frac{E_g}{16}$, so that the difference is $\frac{15E_g}{16}.$