Question

In a hydrogen like atom, when an electron jumps from the M-shell to the L-shell, the wavelength of emitted radiation is $\lambda$. If an electron jumps from N-shell to the L-shell, the wavelength of emitted radiation will be?

• A. $\frac{27}{20}\lambda$
• B. $\frac{16}{25}\lambda$
• C. $\frac{20}{27}\lambda$
• D. $\frac{25}{16}\lambda$

Answer 1

The correct option is C $\frac{20}{27}\lambda$

For M $\to$ L steel
$\frac{1}{\lambda }=K(\frac{1}{2^2}-\frac{1}{3^2})=\frac{K\times 5}{36}$
for N$\to$L
$\frac{1}{{\lambda }^{\prime }}=K(\frac{1}{2^2}-\frac{1}{4^2})=\frac{K\times 3}{16}$
${\lambda }^{\prime }=\frac{20}{27}\lambda$.