What is the symbol used to signify impedance in circuits?

The symbol used to signify impedance in circuits is represented by the letter Z. Impedance is a complex quantity that combines resistance and reactance in an AC circuit and is fundamental in understanding how circuits respond to alternating currents. It encompasses both the opposition to current flow (resistance) and the effects of inductance and capacitance on current flow (reactance).

Using Z as the symbol allows for clear communication in electrical engineering and related fields, as it efficiently captures this dual nature of impedance in its complex form. Thus, when dealing with calculations and discussions regarding AC circuits, Z is the standard notation employed by engineers and technicians alike, making it the correct answer in this context.