Question

Relation between wavelength of photon and electron of same energy is :

• A. $\lambda _{ph} > \lambda _{e}$
• B. $\lambda _{ph} < \lambda _{e}$
• C. $\lambda _{ph}=\lambda _{e}$
• D. $ \frac{\lambda _{e}}{\lambda _{ph}}=$ constant

Answer 1

Answer: (A)

Wavelength $\lambda=\frac{h c}{p}\,\,\{p=\sqrt{2 m E}\}$
$\therefore \lambda=\frac{h c}{\sqrt{2 m E}}$
$\therefore \lambda \propto \frac{1}{\sqrt{m}}$
Mass of photon is less than that of electron.
$\therefore $ wavelength of photon is greater than that of electron $\lambda_{p h}>\lambda_{e}$