Meaning – The term impedance, refers to the combined effect of resistance, inductance, and capacitance on a signal at a given frequency.

In electrical engineering, electrical impedance is the measure of the opposition that a circuit presents to a current when a voltage is applied. Impedance extends the concept of resistance to alternating current (AC) circuits. Impedance possesses both magnitude and phase, unlike resistance, which has only magnitude.

Unlike electrical resistance, electrical impedance’s opposition to current depends on the frequency of the circuit. Resistance can be thought of as impedance with a phase angle of zero.

In the AC circuit, the cumulative effect of reactance and resistance is termed impedance. The impedance is normally denoted by the English letter Z.

Example of usage“While studying the design of electronic systems, the student was required to have a firm grip on fundamental concepts such as resistance, capacitance, and impedance.”