What unit is used to measure electric current?

The unit used to measure electric current is the ampere. This unit quantifies the flow of electric charge in a circuit, specifically indicating the amount of charge that passes a point in the circuit per unit of time. One ampere is defined as one coulomb of charge passing through a point in one second.

Understanding electric current is fundamental in various applications, especially in fields like electrology, where precise control of electrical devices is critical for hair removal processes. In this context, the ampere provides a clear understanding of how much electrical energy is being utilized during treatments.

Other options, such as volt, ohm, and watt, refer to different electrical properties. The volt measures electric potential or voltage, the ohm measures resistance to current flow, and the watt measures power, which is the rate at which energy is used. Each of these units plays an important role in the study of electricity, but they do not represent the flow of electric current itself, making the ampere the correct choice for this question.