Formulas
| Inductive reactance | X_L = 2π · f · L (Ω) |
|---|---|
| Capacitive reactance | X_C = 1 / (2π · f · C) (Ω) |
| Impedance (series RLC) | Z = R + j(X_L − X_C) |
| |Z| | = √(R² + (X_L − X_C)²) |
| Phase angle | φ = arctan((X_L − X_C) / R) |
| Resonance | X_L = X_C at f₀ = 1 / (2π √(LC)) |
X_L (inductor) at common f
| L | 60 Hz | 1 kHz | 100 kHz | 1 MHz |
|---|---|---|---|---|
| 1 µH | 0.38 mΩ | 6.28 mΩ | 0.628 Ω | 6.28 Ω |
| 10 µH | 3.8 mΩ | 62.8 mΩ | 6.28 Ω | 62.8 Ω |
| 100 µH | 37.7 mΩ | 0.628 Ω | 62.8 Ω | 628 Ω |
| 1 mH | 0.38 Ω | 6.28 Ω | 628 Ω | 6.28 kΩ |
| 10 mH | 3.77 Ω | 62.8 Ω | 6.28 kΩ | 62.8 kΩ |
| 100 mH | 37.7 Ω | 628 Ω | 62.8 kΩ | 628 kΩ |
| 1 H | 377 Ω | 6.28 kΩ | 628 kΩ | 6.28 MΩ |
X_C (capacitor) at common f
| C | 60 Hz | 1 kHz | 100 kHz | 1 MHz |
|---|---|---|---|---|
| 10 pF | 265 MΩ | 15.9 MΩ | 159 kΩ | 15.9 kΩ |
| 100 pF | 26.5 MΩ | 1.59 MΩ | 15.9 kΩ | 1.59 kΩ |
| 1 nF | 2.65 MΩ | 159 kΩ | 1.59 kΩ | 159 Ω |
| 10 nF | 265 kΩ | 15.9 kΩ | 159 Ω | 15.9 Ω |
| 100 nF | 26.5 kΩ | 1.59 kΩ | 15.9 Ω | 1.59 Ω |
| 1 µF | 2.65 kΩ | 159 Ω | 1.59 Ω | 0.159 Ω |
| 10 µF | 265 Ω | 15.9 Ω | 0.159 Ω | 16 mΩ |
| 100 µF | 26.5 Ω | 1.59 Ω | 16 mΩ | 1.6 mΩ |
Notes
- Reactance is the imaginary part of impedance — pure inductors and capacitors store energy; ideal ones dissipate none.
- At resonance, reactive parts cancel and the circuit presents pure R.
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