Advantages of AC and DC,Phasor representation,Behaviour of pure resistor for AC excitation,Behaviour of pure Resistor Inductor for AC excitation,Behaviour of pure capacitor for AC excitation,Behaviour of series RL circuit for AC excitation,Impedance triangle for series RL circuit,Active Reactive and Apparent powers,Power triangle for series RL circuit,Behaviour of series RC circuit for AC excitation,Impedance triangle for series RC circuit,Behaviour of series RLC circuit for AC excitation,Advantages of 3-phase over 1-phase system,Star and Delta Connection,Important Questions.