Ohm's Law
The meaning of electrical impedance can be understood by substituting it into Ohm's law.
The magnitude of the impedance acts just like resistance, giving the drop in voltage amplitude across an impedance for a given current . The phase factor tells us that the current lags the voltage by a phase of (i.e., in the time domain, the current signal is shifted later with respect to the voltage signal).
Just as impedance extends Ohm's law to cover AC circuits, other results from DC circuit analysis such as voltage division, current division, Thevenin's theorem, and Norton's theorem can also be extended to AC circuits by replacing resistance with impedance.
Read more about this topic: Electrical Impedance
Famous quotes containing the word law:
“There are no fixtures in nature. The universe is fluid and volatile. Permanence is but a word of degrees. Our globe seen by God is a transparent law, not a mass of facts. The law dissolves the fact and holds it fluid.”
—Ralph Waldo Emerson (1803–1882)