Question

The given 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 the transition from level $\frac{4E}{3}$ to level $E$ is:

• A. $\lambda /3$
• B. $3\lambda /4$
• C. $4\lambda /3$
• D. $3\lambda$

Answer 1

The correct option is A $\lambda /3$

For the transition from one enrgy state to other wavelength of light emitted is given by

$\lambda =hc/\Delta E$

where $\Delta E=E_2-E_1$

given: $\lambda =hc/(2E-E)=hc/E$

for $4E/3\to E$

${\lambda }_2=hc/\Delta E=hc/(4E/3-E)$

${\lambda }_2=hc/3E$

or ${\lambda }_2=\lambda /3$

option D is correct