How is frequency measured in an AC system?

Frequency in an AC (Alternating Current) system is fundamentally measured in Hertz (Hz). Hertz is defined as one cycle per second, which is the standard unit used to quantify the rate of periodic events. In an AC system, the frequency refers to how many times the current alternates or cycles from positive to negative in one second. For example, a frequency of 60 Hz means that the current alternates 60 times every second. This measurement is crucial for understanding the operational characteristics of AC systems, affecting aspects like motor speed, the effectiveness of transformers, and the overall design of electrical systems to match specific applications.

Other units such as Watts, Volts, and Amperes are associated with power, voltage, and current respectively, but do not provide information regarding how frequently the current alternates. Therefore, Hertz is the only unit relevant to measuring frequency in an AC system.