AC Circuits Formulas
AC circuit formulas describe how voltage, current, and impedance interact in sinusoidal systems. These calculators handle reactance, phase, and resonance so you can analyse filters, tuned circuits, and power factor. They are the bridge between simple DC analysis and real-world signals.
AC Circuits Formula Calculators
- Resonant Frequency f = 1 / (2π√(LC))
- Impedance (RLC Series) Z = √(R² + (XL − XC)²)
- Quality Factor (Bandwidth) Q = f₀ / BW
- Quality Factor (RLC) Q = (1/R) × √(L/C)
- Power Factor PF = P / S = cos(φ)
- Apparent Power S = √(P² + Q²)
- Reactive Power Q = S × sin(φ)
- RLC Circuit Bandwidth BW = f0 / Q
- AC RMS / Peak Conversion V_rms = V_peak / √2
- Transformer Turns Ratio N = V1 / V2
- Average Rectified Voltage V_avg = 0.637 × Vpeak
- Three-Phase Line vs Phase Voltage V_line = √3 × V_phase
- Power Factor Correction Capacitor C = Qc / (ω × V²)
- Transformer Efficiency η = Pout / (Pout + Piron + Pcopper)
- Inrush Current I_inrush = Vpeak / Zsource
- Complex Impedance Magnitude (RLC) |Z| = √(R² + (ωL − 1/(ωC))²)
- AC Phase Angle φ = arctan((XL − XC) / R)
- Power Triangle (S, P, Q) S² = P² + Q²
- Phasor Magnitude (Rect → Polar) |Z| = √(R² + X²)
- Phasor Angle (Rect → Polar) θ = atan(X / R)
- Phasor Real Part (Polar → Rect) R = |Z| · cos(θ)
- Phasor Imaginary Part (Polar → Rect) X = |Z| · sin(θ)
- Parallel (Tank) Resonant Frequency f = (1/2π)·√(1/LC − R²/L²)
- Waveform Form Factor FF = Vrms / Vavg
- Peak-to-Peak Voltage Vpp = 2 · Vpeak
- Instantaneous AC Voltage v = Vmax · sin(θ)
- Angular Frequency ω = 2π · f
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