4th Year Lineman Apprentice Practice Exam

Inductive reactance is measured in ohms because it represents the opposition that an inductor offers to the flow of alternating current (AC) due to the inductance of the coil. This opposition arises when the magnetic field around the inductor changes, which creates a counter-emf (electromotive force) that resists the change in current. The formula for calculating inductive reactance (X_L) is given by \(X_L = 2\pi f L\), where \(f\) is the frequency of the AC signal and \(L\) is the inductance in henries.

In context, inductive reactance is a key component in AC circuit analysis, similar to resistance in direct current (DC) circuits. While farads measure capacitance, coulombs measure electric charge, and volts measure electrical potential or voltage, none of these units are applicable to inductive reactance. Understanding that inductive reactance is specifically related to the frequency and inductance in a circuit helps solidify why ohms is the correct unit of measure for this property.