Impedance Triangle Explorer
How to Use
- Resistance R slider — set the resistive component (0–100 Ω). The horizontal side of the triangle.
- Reactance X slider — set the reactive component (−100 to +100 Ω). Positive = inductive (triangle points up), negative = capacitive (triangle points down).
- The right panel shows live calculations of |Z|, θ, and power factor.
What to Observe
- The blue horizontal side represents resistance R — always positive, dissipates power.
- The vertical side is reactance X: red when positive (inductive), green when negative (capacitive).
- The purple hypotenuse is the impedance magnitude |Z|.
- The phase angle θ opens at the origin — positive for inductive, negative for capacitive.
- When X = 0, the triangle collapses to a horizontal line and the circuit is purely resistive.
- When R = 0, the triangle collapses to a vertical line and the circuit is purely reactive (θ = ±90°).
- Power factor = cos(θ) = R/|Z|; ranges from 0 (purely reactive) to 1 (purely resistive).
Key Equations
\[Z = R + jX \quad \text{(rectangular form)}\]
\[|Z| = \sqrt{R^2 + X^2} \quad \text{(Pythagorean theorem)}\]
\[\theta = \tan^{-1}\!\left(\frac{X}{R}\right) \quad \text{(phase angle)}\]
\[Z = |Z|\angle\theta \quad \text{(polar form)}\]
\[\text{Power Factor} = \cos\theta = \frac{R}{|Z|}\]
| Condition | θ | Circuit Type |
|---|---|---|
| X = 0 | 0° | Purely resistive |
| X > 0 | 0° to 90° | Inductive (current lags) |
| X < 0 | 0° to −90° | Capacitive (current leads) |
| R = 0 | ±90° | Purely reactive |
Key Concepts
- Impedance Z: Complex ratio of voltage to current in an AC circuit (Ω)
- Resistance R: Real part of Z — dissipates energy as heat
- Reactance X: Imaginary part of Z — stores and returns energy
- Phase angle θ: Angle by which current lags (positive) or leads (negative) voltage
- Power factor: Fraction of apparent power that does real work