What does impedance refer to in electrical terms?

Impedance in electrical terms is a comprehensive measure that encompasses not only resistance but also the effects of both inductance and capacitance in an electrical circuit. It is represented as a complex number, combining real and imaginary components. The real part corresponds to resistance, which opposes the flow of current, while the imaginary part accounts for reactance, which includes both inductive reactance (from inductors) and capacitive reactance (from capacitors).

This total impedance is crucial for understanding how AC (alternating current) circuits behave, as it affects the voltage and current relationship, phase shifts, and overall circuit performance. In practical applications, accurately calculating impedance enables engineers to design circuits that operate efficiently and predictably across varying frequencies. This characteristic makes understanding impedance essential for anyone working with electrical systems, particularly in utility and utility specialist contexts.