Phasor Imaginary Part (Polar → Rect)

Formula

Description

The imaginary (quadrature) component of a phasor in rectangular form is its magnitude times the sine of the phase angle. This is the reactive part of an impedance or the out-of-phase part of a voltage or current. It stores and returns energy each cycle rather than dissipating it, and it determines the reactive (VAR) power in a circuit.

Variables

• X — Imaginary / quadrature component (Ω)
• |Z| — Phasor magnitude (Ω)
• θ — Phase angle (degrees)

Practical Notes

Positive X is inductive, negative is capacitive. Combine with the real part R = |Z|·cos(θ) to write the impedance as R + jX.