Question

The energies $E_1$ and $,E_2 $ of two radiations are $25 \, eV$ and $50 \, eV$ respectively. The relation between their wavelengths, i.e. $\lambda_1$ and $ \lambda_2$ will be

• A. $\lambda_1 = 2\lambda_2$
• B. $\lambda_1 = 4\lambda_2$
• C. $\lambda_1 = \frac{1}{2}\lambda_2$
• D. $\lambda_1 = \lambda_2$

Answer 1

Answer: (A)

$ E_{1}=25 \,eV , E_{2}=50\, eV $
$ E_{1}=\frac{h C}{\lambda_{1}} $ and $ E_{2}=\frac{h c}{\lambda_{2}}$
or $\frac{E_{1}}{E_{2}}=\frac{\lambda_{2}}{\lambda_{1}}$
or $\frac{25}{50}=\frac{\lambda_{2}}{\lambda_{1}}$
or $\lambda_{1}=2 \lambda_{2}$