ARRL Technician Practice Exam

Electrical current is measured in which of the following units?

1. Volts

2. Ohms

3. Amperes

4. Watts

The correct answer is: Amperes

Electrical current is measured in amperes, often abbreviated as "amps." This unit is named after André-Marie Ampère, a French physicist whose work laid the foundation for the field of electromagnetism. In the context of electrical circuits, current represents the flow of electric charge, typically carried by electrons in a conductor. To clarify the distinctions between the options, volts refer to the unit of electric potential or voltage, which measures the difference in electric potential energy per unit charge. Ohms measure electrical resistance, indicating how much a material opposes the flow of current. Watts, on the other hand, measure electrical power, which is the rate at which energy is transferred or converted. Thus, while volts, ohms, and watts are all important in electrical theory and practice, amperes specifically quantify the flow of electric current.