Electric charge is the amount of electricity a body possesses and there are two types of electric charges; positive and negative. The quantity of charge on a body is measured in coulombs (C).
All matter is made up of tiny particles called atoms. A model of the structure of an atom is shown in the figure below;
The nucleus contains two sub-atomic particles;
- Protons each of them carrying a positive charge.
- Neutrons which carry no charge (neutral).
So overall, the nucleus is positively charged.
The electronic shells surrounding the nucleus carry electrons and each electron carries a negative charge.
The number of electrons is always equal to the number of protons in an atom and it is said to be neutral.