Inductive reactance is the opposition of an inductance to the flow of sinewave alternating current. The symbol for inductive reactance is XL.
Reactance XL is measured in ohms because it limits the current to the value I = V/XL. With V in volts and XL in ohms, I is in amperes.
XL = 2πfL, where f is in hertz, L is in henrys, and XL is in ohms.
With a constant L, XL increases proportionately with higher frequencies.
At a constant frequency, XL increases proportionately with higher inductances.
With XL and f known, the inductance L = XL (2πf).
With XL and L known, the frequency f = XL (2πL).
The total XL of reactances in series is the sum of the individual values, as for series resistances. Series reactances have the same current. The voltage across each inductive reactance is IXL.
The equivalent reactance of parallel Table 20–3 summarizes the differences between L and XL.
Table 20–4 compares XL and R.
Table 20–5 summarizes the differences between capacitive reactance and inductive reactance.
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