Electric Potential

Definition

Electric potential is the amount of work done per unit charge to move a test charge from an infinite distance to a specific point in an electric field. It represents the potential energy per unit charge at a given location and is a scalar quantity, meaning it has magnitude but no direction.

5 Must Know Facts For Your Next Test

1. Electric potential is measured in volts (V), which is the same unit as potential difference.
2. The electric potential at a point is the work done per unit charge in moving a test charge from infinity to that point.
3. The electric potential at a point is independent of the path taken to reach that point, as long as the starting and ending points are the same.
4. The electric potential at a point is directly proportional to the electric charge and inversely proportional to the distance from the charge.
5. Equipotential surfaces are perpendicular to the direction of the electric field, and the electric field is strongest where the equipotential surfaces are closest together.

Review Questions

• Explain how electric potential is related to the work done in moving a test charge within an electric field.
  • The electric potential at a point in an electric field is defined as the amount of work done per unit charge in moving a test charge from an infinite distance to that point. This means that the electric potential represents the potential energy per unit charge at a given location. The difference in electric potential between two points, known as the potential difference, represents the work done per unit charge in moving a test charge between those two points.
• Describe the relationship between electric potential and electric field, and how this is represented by equipotential surfaces.
  • The electric field is a vector quantity, with both magnitude and direction, while electric potential is a scalar quantity, with only magnitude. The electric field is directed from higher to lower electric potential, and the electric field lines are perpendicular to the equipotential surfaces. Equipotential surfaces are imaginary surfaces in an electric field where the electric potential is constant. The electric field is strongest where the equipotential surfaces are closest together, and weakest where they are farthest apart.
• Analyze how the electric potential of a point charge varies with distance from the charge, and explain the significance of this relationship.
  • The electric potential of a point charge is directly proportional to the electric charge and inversely proportional to the distance from the charge. This means that as the distance from the charge increases, the electric potential decreases. This relationship is important because it allows us to understand the potential energy of a test charge in an electric field, which is crucial for analyzing the behavior of charged particles and the flow of electric current. The inverse relationship between electric potential and distance also explains why equipotential surfaces around a point charge are spherical, with the potential decreasing as the distance from the charge increases.

Related terms

Electric Field:

The region surrounding a charged particle or object in which a test charge would experience an electric force. The electric field is a vector quantity, with both magnitude and direction.

Potential Difference:

The difference in electric potential between two points in an electric field. This difference in potential represents the work done per unit charge in moving a test charge between the two points.

Equipotential Surfaces: Imaginary surfaces in an electric field where the electric potential is constant. Points on an equipotential surface have the same electric potential.