Question

The figure indicates the energy levels of a certain atom. When the system moves from 2E level to E, a photon of wavelength $\lambda$ is emitted. The wavelength of photon produced during its transition from $\frac{4E}{3}$ level to E is

• A. $\frac{\lambda}{3}$
• B. $\frac{3 \lambda}{4}$
• C. $\frac{4 \lambda}{3}$
• D. $3\lambda$

Answer 1

Answer: (D)

In the first case, energy emitted, $E_1 = 2E - E = E$
In the second case, energy emitted
$E_{2} = \frac{4E}{3} - E = \frac{E}{3}$
As $E_{2}$ is $\left(\frac{1}{3}\right)^{rd} , \lambda_{2}$ must be $3$ times, i.e. $3\lambda.$