Does a moving charge give more electric field since it has more electromagnetic mass ? Or Let I have a moving charge with speed 0.9c. kinetic energy hence gained is $m 10.5c^2$. Total energy of electron has increased to $11.5mc^2$ Now, let I am moving with 0.9 c. I would see charge at rest. But it has $11.5mc^2$ energy. Does this increased energy emit more electric field? > In 1897, Searle gave a more precise formula for the electromagnetic energy of charged sphere in motion:[5] ![enter link description here][1] [1]: > Electromagnetic mass was initially a concept of classical mechanics, denoting as to how much the electromagnetic field, or the self-energy, is contributing to the mass of charged particles. It was first derived by J. J. So, an increased electromagnetic energy means increased self energy or electromagnetic field. $E = \frac{kq^2}{r}$ So, increased field means increased charge.