Energy of a photon corresponding to a wavelength of 600 nm is 2.08 eV. The energy of a photon of wavelength 400 nm will be:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 3.12 eV
The energy of a photon is \( E = hc/\lambda \), so for photons \( E \propto 1/\lambda \): a shorter wavelength means a larger energy.
\( \displaystyle \frac{E_2}{E_1} = \frac{\lambda_1}{\lambda_2} \;\Rightarrow\; E_2 = 2.08\,\mathrm{eV} \times \frac{600\,\mathrm{nm}}{400\,\mathrm{nm}} = 3.12\,\mathrm{eV} \)