What is the momentum of a photon having the same total energy as an electron with a kinetic energy of 100 keV?

The momentum of the photon is 1.707 x 10⁻²² kg.m/s

Explanation:

Given;

kinetic of electron, K.E = 100 keV = 100,000 eV = 100,000  x 1.6 x 10⁻¹⁹ J = 1.6 x 10⁻¹⁴ J

Kinetic energy is given as;

K.E = ¹/₂mv²

where;

v is speed of the electron

Therefore, the momentum of the photon is 1.707 x 10⁻²² kg.m/s