Relationship between energy and electrical charge?

[Jhenrique]

E=mc² shows the relationship between matter (mass) and energy, but another elementary information in the atomic physics is the electrical charge. So exist some relationship between energy and electrical charge?

 

[Matterwave]

Certainly, see:
http://en.wikipedia.org/wiki/Electric_field#Energy_in_the_electric_field
http://en.wikipedia.org/wiki/Electric_potential

The energy of a spherical distribution of charge Q with radius R can be calculated quite easily as:

$$E=\frac{3}{5}\frac{1}{4\pi\epsilon_0}\frac{Q^2}{R}$$

 

[Simon Bridge]

The famous relationship is properly $E=\gamma mc^2$, where the gamma comes from relativity.
It is an identity - mass is another form of energy.

The Universe has other rules - you cannot freely convert one form of energy into another.
i.e. kinetic energy does not spontaneously turn into gravitational potential energy - you also have to direct the momentum upwards.

As well as conservation of energy, you have to obey other conservation laws.
One of them is a conservation of charge.

The effect of charge is that you can only create charged particles in oppositely charged pairs.