What is the primary unit of frequency?

The primary unit of frequency is Hertz, which is defined as one cycle per second. It is widely used in various fields such as physics and engineering to describe the frequency of waves, including sound waves, electromagnetic waves, and alternating current in electrical circuits. Understanding that frequency is essentially a measurement of how often a repeating event occurs within a specific time period helps clarify why Hertz is the correct answer.

In contrast, Watt is a unit of power, Voltage is a measure of electric potential difference, and Ohm is a unit of resistance in electrical circuits; none of these units relate directly to the concept of frequency. This distinction reinforces the uniqueness of Hertz as the measurement that specifically quantifies cycles per second, making it the fundamental unit for frequency.