Question

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

• A. $1/4$
• B. $4$
• C. $1/2$
• D. $2$

Answer 1

The correct option is D $2$

As we know,

$E=hc/\lambda$

So,

$E_1/E_2={\lambda }_2/{\lambda }_1=4000/2000=2$