Two incandescent light bulbs of $$40$$ $$W$$ and $$60$$ $$W$$ rating are connected in series across the mains. Then

Given two coupled inductors $${L_1}$$ and $${L_2}$$, their mutual inductance $$M$$ satisfies

Consider the star network shown in Fig. The resistance between terminals $$A$$ and $$B$$ with $$C$$ open is $$6\,\Omega ,$$ between terminals $$B$$ and $$C$$ with $$A$$ open is $$11\,\Omega ,$$ and between terminals $$C$$ and $$A$$ with $$B$$ open is $$9\,\Omega $$ . The values of $${R_A},\,\,{R_B},\,\,{R_C}$$ are:

A unit step voltage is applied at $$t = 0$$ to a series $$RL$$ circuit with zero initial conditions.