Practice question

**RMS value** I_rms = I_peak/√2, V_rms = V_peak/√2 for sinusoidal AC, significance rms gives equivalent DC value producing same heating power P = I_rms² R, average power over cycle, instruments measure rms, average over full cycle zero, half-cycle average 2 I_peak/π, peak = √2 rms. Z = √(R² + (X_L - X_C)²) = √(40² + (50 - 30)²) = √(1600 + 400) = √(2000) ≈ 44.72 Ω . RMS current: I = (V/Z) = (120/44.72) ≈ 2.68 A . Power: P = I² R = (2.68)² × 40 ≈ 287.3 W . Applying X_L = ωL, X_C = 1/ωC, Z = √(R² + (X_L -