Question

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

Answer 1

The wavelength of electromagnetic radiation
$\lambda =\frac{c}{v}$
For a photon from De-Broglie hypothesis
$\lambda =\frac{h}{P}$
Since momentum of photon,$p=\frac{hv}{c}$
$\lambda =\frac{hc}{E}$
$\lambda =\frac{c}{v}$
This shows that the wavelength of electromagnetic radiation is equal to the de Broglie wavelength of its quantum (photon).