Practice question

**Capacitive reactance** X_C =1/(ω C)=1/(2π f C) (Ω), C capacitance (F), current leads voltage by 90°, I_rms = V_rms/X_C = V_rms ω C, I_peak = V_peak ω C, impedance Z = X_C for pure C. For 45 μF, 60 Hz, X_C=1/(2π×60×45×10⁻⁶)=58.9 Ω, V_rms=110 V, I_rms=1.867 A, I_peak=2.64 A. Z = √(R² + (X_L - X_C)²) = √(60² + (80 - 20)²) = √(3600 + 3600) = √(7200) ≈ 84.85 Ω . RMS current: I = (V/Z) = (180/84.85) ≈ 2.12 A . Power: P = I² R = (2.12)² × 60 ≈ 269.66 W . Applying X_L = ωL, X_C = 1/ωC, Z = √(R²