What is ax and RL circuits and the difference

Describe AC RL series circuit

the unit of apparent power is VA or mVA not mVAr as above ! VAr is unit of reactive power.

this is a far more comprehensive form of Ohm's Law than what was taught in DC electronics (E=IR), just as impedance is a far more comprehensive expression of opposition to the flow of electrons than resistance is. Any resistance and any reactance, separately or in combination (series/parallel), can be and should be represented as a single impedance in an AC circuit.

Nice video. RL series circuit are very common in electric circuit. A series RL circuit is an electric circuit in which resistor and inductor are in series with each other. Since they are in series the current in both the elements are same. And the sum of voltage drop in resistor Vr and in inductor Vl is equal to the source voltage according to Kirchoffs second law. In these circuits when the power is switched off, the current do not instantly fall to zero but it take a bit time. This happens due to the presence of insuctor which opposes the change in the current according to Faraday's law.