A series AC circuit contains a resistance of 30 ohms, an inductive reactance of 50 ohms, and a capacitive reactance of 10 ohms. What is the impedance of the circuit?

Why B is correct

Net reactance X = XL − XC = 50 − 10 = 40 Ω. Impedance Z = √(R² + X²) = √(30² + 40²) = √(900 + 1600) = √2500 = 50 Ω. Reactive and resistive components add vectorially, not arithmetically, per NEETS Mod. 2 §4-1.