The component of impedance that arises from the resistance portion is called

• A. Resistance
• B. Inductive Reactance
• C. Capacitive Reactance
• D. Real Impedance

Answer: (A)

Impedance has a real part and an imaginary part: Z = R + jX. The real part arises from the resistance, which represents the portion of impedance that dissipates energy as heat. The imaginary part comes from reactance (inductive or capacitive), which stores energy in magnetic or electric fields and causes phase shifts between voltage and current. So the component of impedance due to the resistance is called resistance. (The real part of impedance is equal to R, sometimes referred to as real impedance, but the standard name for that portion is simply resistance.)