Question

Wavelength of the electromagnetic waves emitted due to transition from $L$ to $K-level$ is

• A. $8\times {10}^{-10}m$
• B. $7.104\times {10}^{-11}m$
• C. $22.46nm$
• D. $142.6\times {10}^{-8}m$

Answer 1

The correct option is B $7.104\times {10}^{-11}m$

$E_L-E_K=3\times {10}^{-15}-2\times {10}^{-16}=28\times {10}^{-16}J$
which is equal to $\frac{hc}{\lambda }$
Therefore, wavelength of the emitted electromagnetic waves is:
$\lambda =\frac{(6.625\times {10}^{-34})(3\times {10}^8)}{28\times {10}^{-16}}=7.1\times {10}^{-11}m$