The pure inductors,each of inductance $6 \ H$,are connected as shown in the figure. Their equivalent inductance between the points $P$ and $Q$ is (in $H$)

Two coils of self-inductances $6 mH$ and $8 mH$ are connected in series and are adjusted for the highest coefficient of coupling. The equivalent self-inductance $L$ for the assembly is approximately: (in $mH$)

In the given circuit below, the inductance values of $L_1$, $L_2$, and $L_3$ are the same. The magnetic energy stored in the entire circuit is $U_t$ and that stored in the $L_2$ inductor is $U_l$. The ratio $U_t/U_l$ is . . . . . . . (Ignore the mutual inductance, if any.)

The equivalent inductance between $A$ and $B$ is ..... $H$.

Two identical inductors, each of inductance $L$, are connected in two different configurations $P$ and $Q$, through which a time-varying current $I(t)$ flows. The induced emf between points $a$ and $b$ for configuration $P$ is $E_P$ and that for configuration $Q$ is $E_Q$. The ratio $E_P/E_Q$ is: [Neglect the effect of mutual inductance.]

Two inductors $L_1$ and $L_2$ are connected in parallel,and a time-varying current flows as shown. The ratio of currents $i_1/i_2$ at any time $t$ is: