Where:
XL = inductive reactance, Ohms
f = frequency, Hertz
L = inductance, Henrys
Reactance, XL =
Inductors - Complex Impedance
When working with circuits that contain combinations of ideal capacitances, inductances and resistance, it is more correct to deal with inductance in terms of a "complex impedance". In this form, components have a combination of a "real" resistance part, and an "imaginary" reactance part. The pure inductor, of course, has a zero real part (it doesn't have resistance) but a positive imaginary part.
Where:
j = √-1
XL = inductive reactance, Ohms
ω = angular frequency, radians per second
f = frequency, Hertz
L = inductance, Henrys