Question

Voltage, electric potential difference, electric pressure or electric tension is the difference in electric potential between two points, which (in a static electric field) is defined as the work needed per unit of charge to move a test charge between the two points. What exactly is a point in this definition?

Answer 1

A point in voltage and electric potential difference context is a specific location where electric potential is measured, and the reference or zero potential is arbitrary. The electric potential of a point charge is scalar, denoted by V = kQ/r, distinct from the vector nature of an electric field.

Step-by-step explanation:

In the context of voltage and electric potential difference, a point refers to a specific location in an electric field where the electric potential is measured. When discussing voltage, it is the potential difference between two points that is considered. For example, a battery's voltage is the potential difference between its positive and negative terminals. The choice of the reference or zero potential point is arbitrary, similar to choosing sea level as the reference for gravitational potential energy. The electric potential of a point charge is given by the equation V = kQ/r, where V is the electric potential, k is Coulomb's constant, Q is the charge amount, and r is the distance from the point charge. This measurement is scalar, while the electric field is a vector.