Question

The following diagram 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. $\lambda/3$
• B. $3\lambda/4$
• C. $4\lambda/3$
• D. $3\lambda$

Answer 1

Answer: (D)

$3\lambda$

Answer 2

$2E - E = \frac{hc}{\lambda} \Rightarrow E = \frac{hc}{\lambda}$

$\frac{4E}{3} - E = \frac{hc}{\lambda'} \Rightarrow \frac{E}{3} = \frac{hc}{\lambda'}\mspace{6mu}\mspace{6mu}\therefore\frac{\lambda'}{\lambda} = 3 \Rightarrow \lambda' = 3\lambda$.