What is the SI unit of voltage?

The SI unit of voltage is the volt, which is a measure of electric potential difference between two points in an electrical circuit. It quantifies how much energy per unit charge is available to drive the flow of electrical current. The volt is defined such that one volt corresponds to one joule of energy per coulomb of charge. This relationship makes it essential for understanding how electrical energy is transferred in systems, such as those found in HVACR applications.

In contrast, other units provided serve different purposes in the field of electricity. The watt is the unit of power, indicating the rate at which electrical energy is consumed or produced. The ohm is the unit of resistance, specifying how much a material resists the flow of electric current. The ampere, on the other hand, is the unit of electric current, representing the flow of electric charge. Therefore, while all these units are integral to the understanding of electrical systems, the volt specifically relates to voltage, making it the correct choice.