Calculate the equivalent impedance in complex and polar forms
This calculator determines the equivalent impedance of a resistor and inductor connected in parallel in an AC circuit. The result is presented as a complex number in both standard and polar forms, giving you complete information about the impedance magnitude and phase angle.
For a parallel RL circuit, where:
The impedance of the inductor is given by:
\(Z_L = j\omega L\)
The equivalent impedance \(Z\) of the parallel RL circuit is:
\(\dfrac{1}{Z} = \dfrac{1}{R} + \dfrac{1}{Z_L}\)
Which simplifies to:
\(Z = \dfrac{R Z_L}{R + Z_L} = \dfrac{j R \omega L}{R + j\omega L} = \dfrac{1}{\dfrac{1}{R} - j\dfrac{1}{\omega L}}\)
The magnitude (modulus) and phase angle of the impedance are:
Modulus: \(|Z| = \dfrac{1}{\sqrt{\dfrac{1}{R^2} + \dfrac{1}{\omega^2 L^2}}}\) in ohms (Ω)
Phase angle: \(\theta = \arctan\left(\dfrac{R}{\omega L}\right)\) in radians or degrees
Enter the values for resistance, inductance, and frequency to calculate the impedance: