Practice question

**AC through inductor** voltage leads current by 90°, V = L dI/dt, V(t)=V_peak sin(ωt+90°), I(t)=I_peak sin ωt, instantaneous power P= V I =½ V_peak I_peak sin2ωt, average zero over cycle because energy stored in magnetic field ½ L I² returned to source each quarter cycle, no net dissipation. X_L = ω L , ω = 2π × 60 = 376.8 rad/s . L = 65 × 10⁻³ H . X_L = 376.8 × 0.065 = 24.49 Ω . RMS current: I = (V/X_L) = (110/24.49) ≈ 4.49 A . Applying X_L = ωL, X_C = 1/ωC, Z = √(R² + (X_L - X_C)²), I_rms =