In which circuit will the current be maximum immediately after closing the switch $S$?

$A$ long coaxial cable carries current $I$ along its surface. The current flows down the surface of the inner cylinder of radius $a$ and back along the outer cylinder of radius $b$.

In the given circuit, if $dI/dt = -1 \text{ A/s}$, then the value of $V_{AB}$ at this instant will be: (in $\text{ V}$)

Current in a circuit falls from $5.0\, A$ to $0\, A$ in $0.1\, s$. If an average $emf$ of $200\, V$ is induced,estimate the self-inductance of the circuit in $H$.

Which of the following units denotes the dimensions $\frac{M L^2}{Q^2}$,where $Q$ denotes the electric charge?

$A$ coil is wound on a core of rectangular cross-section. If all the linear dimensions of the core are increased by a factor of $3$ and the number of turns per unit length of the coil remains the same,the self-inductance increases by a factor of: