## Electric charge

### Définition :

Electric charge it is a scalar quantity, representing a fundamental property of matter that helps explain certain phenomena (electrostatics, electromagnetism, etc.).

There are two types of electric charge, positive and negative.

Elementary charge: This is the smallest amount of charge Q= |e| = 1.602176634x10-19 C

the electrical charge of an:

electron : Qe = -e = -1.602176634x10-19 C

and proton : Qp = +e = +1.602176634x10-19 C

Two charges of the same sign repel each other, and two charges of opposite signs attract each other.

### Définition : Point charge

it is an electric charge localized at a dimensionless point.

### Définition : conservation of electric charge

In an isolated body, the algebraic sum of electric charges remains constant: qfinal = qinitial