Inductive Reactance
Xₗ = 2πfL
Opposition offered by an inductor to AC current flow.
Capacitive Reactance
Xᴄ = 1 / (2πfC)
Opposition offered by a capacitor to AC current flow.
Series Impedance
Z = √(R² + X²)
Total opposition to AC current in a series R-X circuit.
RMS Voltage
Vᵣᵐₛ = Vₚₑₐₖ / √2
RMS (effective) value of a sinusoidal AC voltage.
Resonant Frequency
fᵣ = 1 / (2π√(LC))
Frequency at which inductive and capacitive reactances cancel.