What does frequency measure in an electrical circuit?

Frequency measures the number of cycles in one second in an electrical circuit. This concept is fundamental in understanding alternating current (AC) systems where the current changes direction periodically. A cycle is defined as one complete waveform from beginning to end, including both its positive and negative phases.

In practical terms, frequency is measured in hertz (Hz), where one hertz equals one cycle per second. This characteristic is crucial for various applications, including radio communications, where different frequencies allow for different channels, and in power systems, where maintaining the standard frequency (like 60 Hz in North America) ensures the consistent operation of electrical devices.

The other concepts mentioned, such as resistance, flow of electrons, and electrical pressure, relate to other aspects of electrical circuits. Resistance pertains to the opposition to the flow of current, the flow of electrons indicates the actual movement of charge, and electrical pressure (voltage) refers to the potential difference that drives the flow. However, these do not describe what frequency specifically measures within an electrical circuit.