Question

Show that the wavelength of electromagnetic radiation is equal to the de Broglie wavelength of its quantum (photon).

Answer 1

We know momentum of photon, $p=\frac{h}{\lambda }$

$\Rightarrow \lambda =\frac{h}{p}-\left(1\right)$

De broglie wavelength of photon, $\lambda =\frac{h}{mv}$

Also, $p=mv$

$\therefore \lambda =\frac{h}{p}-\left(2\right)$

From $\left(1\right)$ and $\left(2\right)$, it can be inferred that wavelength of electromagnetic and de-Broglie are same.