Viva Question on Single Phase AC Circuits
Viva Question on Single Phase AC Circuits Q.1. What is the phase relationship between the supply voltage and current flowing through a purely resistive circuit? Ans. Both supply voltage and circuit current are in phase with each other. Q.2. What is the phase relationship between the supply voltage and current flowing through a purely inductive circuit? Ans. In a purely inductive circuit current lags behind the supply voltage by 90° or π/2 radians. Q.3. Why are the inductors usually iron cored? Ans. Inductors or choke coils are made of the iron core because large valued flux densities cab be produced in iron cores and so inductances of large value can be had. Air-cored inductors become too much bulky to provide an inductance of a required value. Q.4. Does an inductance draw instantaneous power as well as average power? Ans. An inductance draws instantaneous power but no average power. The power drawn by inductance during a one-quarter cycle is released in anothe...