In an AC circuit, the impedance Z is a complex quantity with units of ohms. What is the units of R and X individually?

In an AC circuit, the impedance Z is a complex quantity with units of ohms. What is the units of R and X individually?

• A. Volts
• B. Ohms
• C. Amperes
• D. Webers

Answer: (B)

In AC circuits, impedance is written as Z = R + jX, where R is the resistance (the real part) and X is the reactance (the imaginary part). Since Z is measured in ohms, its components must share the same unit. That means both R and X carry the unit of ohms. The sign of X can indicate inductive (positive) or capacitive (negative) behavior, but the unit remains ohms. The other options (volts, amperes, webers) are not units for resistance or reactance.

In AC circuits, impedance is written as Z = R + jX, where R is the resistance (the real part) and X is the reactance (the imaginary part). Since Z is measured in ohms, its components must share the same unit. That means both R and X carry the unit of ohms. The sign of X can indicate inductive (positive) or capacitive (negative) behavior, but the unit remains ohms. The other options (volts, amperes, webers) are not units for resistance or reactance.