Practise calculating the total gamma-photon energy released when an electron and positron annihilate using E = 2mc², checking the particle masses and units.
An electron, at rest, has mass me and charge -q.
A positron is a particle that, at rest, has mass me and charge +q.
A positron interacts with an electron. The electron and the positron may be considered to be at rest.
The outcome of this interaction is that the electron and the positron become two gamma-ray ( γ-ray) photons, each having the same energy.
Calculate, for one of the γ-ray photons:
the photon energy, in J
energy =
E=mc2
C1
=9.11×10−31×(3.0×108)2=8.2×10−14 J
A1