$A$ 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

Two coils with self-inductance $1 H$ and $3 H$ are connected in series. Their mutual inductance is $5 H$. The equivalent self-inductance of the combination is: (in $H$)

Three inductances are connected as shown in the figure. The equivalent inductance is

An inductor coil of inductance $L$ is divided into two parts and both parts are connected in parallel. The net inductance is

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 inductance between $A$ and $D$ is