What does an amp measure?

An ampere, often shortened to amp, is defined as a unit of electric current. It measures the amount of charge passing a point in an electric circuit per unit time. Specifically, one ampere corresponds to one coulomb of charge moving past a given point in one second. This foundational concept in electrical engineering and physics plays a crucial role in understanding how electrical systems function, as current flow is essential for electronic devices to operate.

Understanding that current is a measure of the flow of electrons helps clarify how electrical circuits work and is fundamental for both theoretical and practical applications in technology and engineering. The other choices pertain to different electrical concepts, such as voltage (electrical potential difference), resistance (the opposition to current flow), and power (the rate at which electrical energy is transferred), but they do not define what an ampere measures.