Electric Fields

An electric field is an area surrounding a charged particle or object that can influence other charged particles or objects. Although you cannot see an electric field, when another charged object enters the field, a non-contact force acts on it.

A non-contact force is a force that acts on an object without physically touching it. As the charged objects do not need to touch for the forces to act on them, it is a non-contact force.

Electric fields are typically shown using electric field lines, which are diagrams with arrows.

The field lines always go:

  • Outwards, away from positive charge.
  • Inwards, towards negative charge.

The electric fields can be drawn like the diagrams below.

It is important to note :

  • The direction of the field lines is the same as the direction of the force acting on a positively charged particle in the electric field.
  • The strength of the electric field is related to the distance between the field lines. The further the distances between the field lines are, the weaker the field. Keep in mind, that the greater the distance from the charged object is, the weaker the electric field will be. You can see this visually, as the field lines get further apart the further you get from the charged particle.

Below is the electric field between two opposite charges.