impedance (electrical)

of: a single electrical component or a two terminal network, in which an alternating current of peak value flows in response to an externally supplied alternating voltage of peak value

is: the quantity [P5.4, P5.5]

is analogous: to the resistance of a d.c. circuit component. [P5.4, P5.5]

is given: by where is the resistance and is the reactance of the component or network. [P5.4]

has as its SI unit: the ohm [P5.4, P5.5]

generally depends: on the angular frequency of the supply (since depends on that frequency)

is at a minimum: for a series LCR circuit at the circuit's natural frequency. [M6.3, P5.3, P5.4]

is at a maximum: for a parallel LCR circuit at the circuit's natural frequency. [M6.3, P5.3, P5.4]