Test: Inductive & Non-Inductive Circuits - Electrical Engineering (EE) MCQ

The formula for frequency in an inductive circuit is:
X_L=2*π*f*L.
Therefore: f is inversely proportional to L.

Inductance is inversely proportional to current since, as the inductance increases, current decreases.

 The power factor, that is, cos(phi) is equal to the resistance divided by the impedance in the circuit, hence as impedance increases, the power factor decreases.

The power factor is the cosine of the angle in between the voltage and the current. If the angle between the voltage and current is 90, then cos90=0. Hence, the power factor is zero.

In a pure inductive circuit, current is lagging by 90 degrees from the voltage. The power factor is the cosine of the angle in between the voltage and the current. If the angle between the voltage and current is 90, then cos90=0. Hence, the power factor is zero.

We know that:
cos(φ)=R/Z

given Z = 20 ohm, cos(φ) = 1/10

so R comes out to be 2 ohm.

We know that:
cos(ϕ) = R/Z = 2/20 = 1/10 ohm.

We know that:
cos(phi) = R/Z
From the given question, we find that the inductive reactance is 20 ohm.

Inductive reactance is nothing but the impedance. Impedance is the AC equivalent of resistance, hence the unit for inductive reactance is ohm.

Any circuit in which a change of current is accompanied by a change of flux, and therefore by an induced emf, is said to be inductive.