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Impedance consists of the vector sum of resistance and reactance.
The moving magnetic field produced by a change in current causes an induced voltage to oppose the original change. Circuit having greater inductive reactance than capacitive reactance. Measured in Ohms and varies in direct proportion to frequency. The conductor is usually wound into a coil to concentrate the magnetic lines of force and maximize the inductance. While any conductor has inductance, in common usage the term inductor usually refers to a coil.