# AQA A-Level Physics/Electric Fields

Electric Fields

Coulomb’s Law-This law is about the force between two point charges in a vacuum.

Electric Field Strength-The electric field strength E is the force per unit charge, it’s unit is the newton per Coulomb.

The magnitude of E in a radial field is given by the equation below.

The magnitude of E in a uniform field is given by the equation where V is the potential difference between the two plates and d is the distance between the two plates.

Electrical Potential:

Absolute Electrical potential is the amount of potential energy needed to move a unit positive charge from infinity to a specific point within the field. The electric potential at infinity is assumed to be zero.

E against r: