10.7: Electric Potential

Describe the electric potential due to a configuration of charged objects

Electric potential describes the electric potential energy per unit charge at a point in space.

The electric potential due to multiple point charges can be determined by the principle of scalar superposition of the electric potential due to each of the point charges.

Electric potential difference between two points is the change in electric potential energy per unit charge when a test charge is moved between the two points.

• Electric potential difference may also result from chemical processes that cause positive and negative charge to separate, such as within a battery.

Describe the relationship between electric potential and electric field

The average electric field between two points in space is equal to the electric potential difference between the two points divided by the distance between the two points.

Electric field vector maps and equipotential lines are tools to describe the field produced by a charge or configuration of charges, and can be used to predict the motion of charged objects within the field.

• Equipotential lines represent lines of equal electric potential in space. These lines are also referred to as isolines of electric potential.

• Isolines are perpendicular to electric field vectors. An isoline map of electric potential can be constructed from an electric field vector map, and an electric field map may be constructed from an isoline map.

• An electric field vector points in the direction of decreasing potential.

• There is no component of an electric field along an isoline