AC Circuits

AC circuit calculators and formulas for reactance, impedance, and resonance in alternating-current circuits. Covers capacitive reactance, inductive reactance, and resonant frequency calculations.

10Formulas

All levels Difficulty

Updated Oct 2026

← All Electrical Engineering (168) AC Circuits (10)

Fundamental

Skin Depth (Copper, Steel, Conductivity)

δ = √(2ρ / (ωμ))

Fundamental

Admittance Calculator – Calculate Y, Conductance & Susceptance

Y = 1 / Z

Fundamental

RLC Series Impedance

Z = R + j(X_L − X_C)

Fundamental

Phasor Voltage Representation

V = V_m∠θ

Fundamental

Bandwidth of a Resonant Circuit

BW = f₀ / Q

Fundamental

Quality Factor (Series RLC)

Q = ω₀L / R

Fundamental

Angular Frequency

ω = 2π·f

Fundamental

Impedance of a Capacitor

Z_C = 1 / (jωC)

Fundamental

Impedance of an Inductor

Z_L = jωL

Fundamental

Impedance of a Resistor

Z_R = R