The current in a coil decreases from $1 \, A$ to $0.2 \, A$ in $10 \, s$. Calculate the coefficient of self-inductance if the induced $e.m.f.$ is $0.4 \, V$. (in $, H$)

When a current of $1 \,A$ is passed through a coil of $100$ turns, the flux associated with it is $2.5 \times 10^{-5} \,Wb/\text{turn}$. The self-inductance of the coil in millihenry is:

An air-cored solenoid with length $30 \ cm$,area of cross-section $25 \ cm^2$ and number of turns $500$ carries a current of $2.5 \ A$. The current is suddenly switched off for a brief time of $10^{-3} \ s$. How much is the (nearly) average back e.m.f. induced across the ends of the open switch in the circuit (in $V$)? (Ignore the variation of magnetic field near the ends of solenoid)

The momentum in mechanics is expressed as $m \times v$. The analogous expression in electricity is

In the given circuit,what happens when the switch $S$ is opened?

The network shown in the figure is a part of a circuit. (The battery has negligible internal resistance). At a certain instant,the current is $2 \ A$ and it is decreasing at the rate of $10^2 \ A \ s^{-1}$. What is the potential difference between the points $B$ and $A$ (in $V$)?