An electron has a total energy of 2.8 MeV. What is its momentum?

Answer 1

In c = 1 units:

E^2 - p^2 = m^2 ------>

p = sqrt[E^2 - m^2] =

sqrt[2.8^2 - 0.511^2] MeV =

2.753 MeV

Put c back by dividing by c

p = 2.753 MeV/c = 1.47*10^(-21) kg m/s