To understand the concept of reactance (of an inductor) and itsfrequency dependence.
When an inductor is connected to a voltage source that variessinusoidally, a sinusoidal current will flow through the inductor,its magnitude depending on the frequency. This is the essence of AC(alternating current) circuits used in radio, TV, and stereos.Circuit elements like inductors, capacitors, and resistors arelinear devices, so the amplitude I0 of the current will beproportional to the amplitude V0 of the voltage. However,the current and voltage may not be in phase with each other. Thisnew relationship between voltage and current is summarized by thereactance, the ratio of voltage and current amplitudes,V0, and I0:XL=V0/I0, where the subscript Lindicates that this formula applies to an inductor.
What is the reactance XL of an inductor?
