Question

What is the energy equivalent of the mass of an electron?

Answer 1

The invariant mass of an electron is approximately9.109×10−31 kilograms, or5.489×10−4 atomic mass units. On the basis of Einstein's principle of mass–energy equivalence, this mass corresponds to a rest energy of 0.511 MeV. The ratio between the mass of a proton and that of an electron is about 1836.