What does frequency (in Hz) represent in electrical terms?

Frequency, measured in hertz (Hz), specifically refers to the number of cycles per second of alternating current (AC). In AC systems, the electrical current alternates direction periodically, and the frequency indicates how many complete cycles of this alternating flow occur in one second. For example, a frequency of 60 Hz means that the current changes direction 60 times in one second. This characteristic is crucial in understanding how electrical systems operate, especially in relation to appliances and devices that rely on AC power.

The other options pertain to different electrical properties: voltage refers to the electrical potential difference, resistance measures how much a material opposes the flow of electric current, and total current indicates the flow of electric charge through a circuit. Each of these are distinct concepts that do not define frequency. Therefore, identifying frequency as the number of cycles of AC per second is critical in understanding the behavior of electrical currents.