Calculateur d'Impédance AC Gratuit
Calculez l'impédance d'un circuit en courant alternatif. Déterminez l'impédance complexe avec résistance et réactance.
Impedance (Z)
122.0656 Ω
Impedance (Z) vs Resistance (R)
Formule
AC Impedance
Impedance is the total opposition to current flow in an AC circuit, including both resistance and reactance.
Formula
Z = sqrt(R² + (XL - XC)²)
where XL = 2*pi*f*L is inductive reactance and XC = 1/(2*pi*f*C) is capacitive reactance. The phase angle is phi = arctan((XL - XC) / R).
Exemple Résolu
A series RLC circuit with R = 100 Ω, XL = 150 Ω, XC = 80 Ω.
- 01Z = sqrt(R² + (XL - XC)²)
- 02Z = sqrt(100² + (150 - 80)²)
- 03Z = sqrt(10000 + 4900)
- 04Z = sqrt(14900) = 122.07 Ω
- 05phi = arctan(70/100) = 34.99°
Questions Fréquentes
What is the difference between resistance and impedance?
Resistance opposes DC and AC equally. Impedance is the AC equivalent that includes reactance from capacitors and inductors, causing phase shifts.
When is impedance minimized?
When XL = XC (resonance). At resonance, impedance equals pure resistance R, and the circuit passes maximum current.
What does the phase angle mean?
It indicates the time difference between voltage and current peaks. Positive phase means current lags voltage (inductive); negative means current leads (capacitive).
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