What is the unit of impedance?

Impedance is the total opposition to alternating current (AC) in a circuit, combining the effects of simple resistance with the dynamic effects of reactance from inductors and capacitors. Because it represents a restriction of current flow exactly like resistance does in a DC circuit, it shares the same unit of measurement: the ohm. Even though impedance encompasses complex alternating current behaviors, you calculate and measure it using ohms. The other choices are incorrect because volts measure electromotive force, amperes measure current flow, and coulombs measure charge.