Inductive Element in Series AC Circuit
- The voltage always leads the current by a quarter of a period across an inductor, f = 90 0 = 2p/4 = p/2.
- An inductor as a circuit element follows a modified form of Ohm's law, "V = R I"
- Here XL is the effective ohmic resistance of the inductor called the inductive reactance or more generally the impedance of an inductor.
- To find the voltage at any given moment in time one must multiply by the effective resistance XL by the current not at that moment but by the current in the inductor T/4 seconds later, i.e. at t + T/4.
- The voltage in an inductor has its greatest value when the current changing most rapidly, and is zero when the current is at its maximum or minimum value.
- An inductor cannot dissipate any energy in series AC circuit. The inductor stores energy in its magnetic field as current increases and releases it when current is decreasing.