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.)

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.]

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 $H$)

When three inductors of same inductance $L$ are connected in series and $I$ is the current passing through the circuit,the energy stored in the circuit is:

Two coils of self-inductance $L_{1}$ and $L_{2}$ are connected in series. If the mutual inductance of the coils is $M$,the equivalent self-inductance of the combination shown in the figure will be:

$A$ circuit contains two inductors of self-inductance $L_1$ and $L_2$ connected in series as shown in the figure. If $M$ is the mutual inductance between them,then the effective inductance of the circuit will be