What is the unit of electrical resistance called?

The unit of electrical resistance is called the ohm. This measurement describes how much a conductor resists the flow of electric current. The resistance is determined by the physical properties of the material (such as its length, cross-sectional area, and type of material) and is key to Ohm's Law, which relates voltage, current, and resistance in an electrical circuit.

The other options represent different electrical concepts: the watt measures power, which is the rate at which electrical energy is transferred or converted; the volt measures electrical potential or voltage, which signifies the potential difference that drives current flow; and the joule measures energy, which is the work done when a current is applied over a period of time. Understanding the specific definitions and applications of these units is essential in grasping electrical concepts and their interactions within circuits.