What does the volt measure?

What does the volt measure?

• A. Electric potential energy
• B. Electric current
• C. Electric resistance
• D. Electric potential difference

Answer: (D)

Voltage is the electric potential difference between two points, and it’s measured in volts. One volt means one joule of energy per coulomb of charge moving between those points. So the volt tells you how much energy per unit charge is available to move from one point to another, not the total energy or the amount of current. For example, a 9-volt source creates a difference of 9 joules per coulomb between its terminals, so moving 1 coulomb across it would involve 9 joules of energy. It’s a relative quantity you measure with a device across two points, and it’s distinct from electric potential energy (which is energy of a specific charge), electric current (the flow of charge), or resistance (how much a component resists that current).

Voltage is the electric potential difference between two points, and it’s measured in volts. One volt means one joule of energy per coulomb of charge moving between those points. So the volt tells you how much energy per unit charge is available to move from one point to another, not the total energy or the amount of current. For example, a 9-volt source creates a difference of 9 joules per coulomb between its terminals, so moving 1 coulomb across it would involve 9 joules of energy. It’s a relative quantity you measure with a device across two points, and it’s distinct from electric potential energy (which is energy of a specific charge), electric current (the flow of charge), or resistance (how much a component resists that current).