Dear student, I think you want to know the S.I unit of impedance. Impedance is a complex number, with the same units as resistance, for which the SI unit is the ohm (Ω).They both are obtained by dividing the given potential difference with current. Its symbol is usually Z, and it may be represented by writing its magnitude and phase in the form |Z|∠θ. Impedance is the measure of the opposition that a circuit presents to a current when a voltage is applied. The term complex impedance may be used interchangeably.

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