When a current in the conducting coil is changed from $5 \ A$ in one direction to $5 \ A$ in the opposite direction in $0.5 \ s$,an average induced e.m.f. in the coil is $2 \ V$. The self-inductance of the coil is (in $mH$)

$A$ circuit having a self-inductance of $1 \text{ H}$ carries a current of $1 \text{ A}$. To prevent sparking when the circuit is broken,a capacitor which can withstand $500 \text{ V}$ is connected across the switch. What is the minimum value of the capacitance of the capacitor (in $\mu \text{ F}$)?

$A$ solenoid is connected to a battery so that a steady current flows through it. If an iron core is inserted into the solenoid, then the current in the coil

If $R$ and $L$ represent respectively resistance and self-inductance,which of the following combinations has the dimensions of frequency?

Explain self-induction and obtain the equation for the self-induced $emf$ in a coil.

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: