Electric Field Definition
- An electric field is a region of space in which an electric charge experiences a force
- The electric field at a point is defined as:
The electrostatic force per unit positive charge acting on a stationary point charge at that point
- It is important to use a positive test charge in this definition, as this determines the direction of the electric field
- An electric field is always directed:
- Away from a positive charge
- Towards a negative charge
Electric Field Lines for Positive and Negative Charges
Electric fields are always directed away from positive charges and towards negative charges
- Recall that opposite charges (positive and negative) charges attract each other
- Conversely, like charges (positive and positive or negative and negative) repel each other
Attraction and Repulsion of Charges
Like charges repel; opposite charges attract