Question

The ratio of the energy of a photon of $2000\stackrel{o}{A}$ wavelength radiation to that of $4000\stackrel{o}{A}$ radiation is:

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

Answer 1

The correct option is D $2$

To find the ratio of the energy of a photon to the radiation, let us find $E_1$ and $E_2$
$E=\frac{hc}{\lambda }$
$\Rightarrow \frac{E_1}{E_2}=\frac{{\lambda }_2}{{\lambda }_1}=2$
Thus, we have the ratio of energies $\frac{E_1}{E_2}=2$.