Reactance occurs in circuits that contain capacitors and inductors and describes how the voltage in the circuit is out of phase with the current.
Resistive elements in a circuit have a single resistance value, whereas reactance describes a curve of values that differ at various frequencies.
To compute inductive and capacitive reactance, two equations are used, one involving omega (ω) and the other involving mu (μ) and epsilon (ε).
Understanding the derivation of these equations relies on knowledge of calculus, with hackaday.com suggesting that beginners in the field might experience panic upon studying the topic.
However, the website also states that calculus is “not as hard as you think” to master and is a necessary tool for many areas of electrical engineering and physics.