$A$ choke coil works on the principle of

The magnetic flux through a circuit carrying a current of $2.0\,A$ is $0.8\,Wb$. If the current reduces to $1.5\,A$ in $0.1\,s$,the induced $emf$ is......$V$.

The self-inductance $L$ of a solenoid of length $l$ and area of cross-section $A$,with a fixed number of turns $N$,increases as:

Consider a solenoid carrying current supplied by a $DC$ source with a constant $emf$ containing an iron core inside it. When the core is pulled out of the solenoid,the change in current will:

Current in a circuit falls from $5.0 \ A$ to $0.0 \ A$ in $0.1 \ s$. If an average emf of $100 \ V$ is induced,then the value of self-inductance of the circuit is . . . . . . . (in $H$)

In the given circuit, if $\frac{dI}{dt} = -1 \, A/s$, then the value of $(V_A - V_B)$ at this instance will be (in $\, V$)