When a resistive AC circuit contains inductance the total opposition to current flow is called?

Answer 1

The resistance of an a.c. load is called 'resistance' (R). Resistance is not affected by frequency, only by the cross-sectional area, length, and resistivity of the conductor. Having said that, because of the skin effect, which causes an a.c. current to flow closer to the surface of the conductor, the effective cross-sectional are is reduced, so the value of a.c resistance is somewhat higher than the d.c. resistance -this difference increases with frequency.

The opposition to a.c due to inductive or capacitive loads is called reactance (inductive reactance or capacitive reactance), and the overall opposition to a.c. current is the vector sum of resistance and reactance, and is called impedance. That is:

(impedance)2 = (resistance)2 + (reactance)2

Answer 2

An inductive load opposes a.c. current due to its inductive reactance (symbol: Xc), expressed in ohms. Inductive reactance is directly-proportional to the inductance (expressed in henrys) of the load and the frequency (expressed in hertz) of the supply.

The overall opposition of an resistive-inductive circuit to a.c. current is the vectorial-sum of a load's resistance and inductive reactance is termed impedance (symbol: Z), and is also expressed in ohms.