In the circuit shown in Figure, it is desired to have a constant direct current $$i(t)$$ through the ideal inductor $$L.$$ The nature of the voltage source $$v(t)$$ must be

Energy stored in a capacitor over a cycle, when excited by an $$a.c.$$ source is

The v - i characteristic as seen from the terminal pair (A,B) of the network of Fig.(1) is shown in Fig.(2). If an inductance of value 6 mH is connected across the terminal - pair (A,B), the time constant of the system will be

All the resistances in the circuit of Fig. are of 1 $$\Omega$$ each. The value of current 'I' is