Impedance comprises which components?

• A. Resistance, conductance, and susceptance
• B. Resistance, capacitive reactance, and inductive reactance
• C. Resistance only
• D. Inductive reactance only

Answer: (B)

The key idea is that impedance combines a real, loss-causing part with a reactive part that stores and returns energy. In AC circuits, impedance is written as Z = R + jX, where R is the resistance (the real part) and X is the net reactance (the imaginary part). The reactance comes from both capacitors and inductors, with X = XL − XC. So impedance includes resistance plus both forms of reactance, not just one kind or admittance terms. That’s why the statement that lists resistance together with capacitive reactance and inductive reactance best describes impedance. The other options misstate impedance by focusing only on resistance, or only one type of reactance, or by using admittance concepts (conductance and susceptance) instead of impedance.