A solenoid has an inductance of 50 henry and a resistance of 30 ohm. If it is connected to
a 100 volt battery, how long will it take for the current to reach one-half of its final
equilibrium value?
The average value for half cycle in a 200 V AC source is
A closed circuit consists of a source of emf E and an inductor coil of inductance L, connected in series. The active resistance of whole circuit is R. At the moment t = 0, inductance of coil abruptly decreased to L/n. Then current in the circuit immediately after, is