Use the Einstein relation E = hf and the relation E = pc to show that the de Broglie relation A.3 holds for photons.

Solution 3P

Given in the question are two energy magnitudes. We can equate the both equations and then arrive at the desired expression. The steps are discussed below.

Step 1

Given, …..(1)

Here, Planck’s constant

frequency of a photon

The energy of a photon with momentum and speed is

…..(2)