Practice question

**Average power** in resistor P_avg = V_rms I_rms = V_rms²/R = I_rms² R, for 254.6 V peak, V_rms =180 V, R=90 Ω, P=180²/90=360 W, for 226.3 V peak, V_rms=160 V, R=80 Ω, P=320 W, illustrating rms use for power. "Wattless current" refers to the component of current in a purely reactive (inductive or capacitive) AC circuit that is 90° out of phase with the voltage. It does not contribute to average power dissipation, as power is zero when cos 90° = 0 , hence "wattless.". Applying X_L = ωL, X_C = 1/ωC, Z = √(R² + (X_L - X_C)²), I_rms = V_rms/Z, P = V_rms