What unit is used to measure frequency?

The correct unit used to measure frequency is Hertz. Frequency is defined as the number of occurrences of a repeating event per unit of time. In the context of wave motion, such as sound or electromagnetic waves, frequency specifies how many cycles occur in one second. The unit of Hertz (Hz) represents one cycle per second.

Understanding why Hertz is the appropriate choice involves recognizing the definitions of other units listed. Joules are used to measure energy, Pascals measure pressure, and Volts measure electrical potential. Each of these units serves a distinct purpose in physics, but they do not relate to the measurement of how often an event occurs within a given time, as frequency does. Therefore, Hertz is the unit that accurately captures the concept of frequency in various scientific and engineering applications.