The inductance of a coil is $60\,\mu H$. $A$ current in this coil increases from $1.0\,A$ to $1.5\,A$ in $0.1\,s$. The magnitude of the induced $e.m.f.$ is

$A$ wire in the form of a tightly wound solenoid is connected to a $DC$ source and carries a current. If the coil is stretched so that there are gaps between successive elements of the spiral coil,will the current increase or decrease? Explain.

$A$ toroid is a long coil of wire ($N$ turns) wound over a circular core. The coefficient of self-induction of the toroid is [The magnetic field in it is uniform and $R >> r$,where $r=$ radius of wire,$R=$ radius of coil] ($\mu_0=$ permeability of free space).

$A$ solenoid is tightly wound with wire of diameter $0.10\,cm$,has a cross-sectional area $\frac{1}{\pi}\,cm^2$,and is $40\,cm$ long. If the current through the solenoid decreases uniformly from $10\,A$ to $0\,A$ in $0.10\,s$,then the $emf$ induced inside the solenoid is.....$mV$.

The self-inductance of a circuit is numerically equal to

$A$ branch of a circuit is shown in the figure. If the current is decreasing at the rate of $10^3 \ A \ s^{-1}$, then the potential difference between $A$ and $B$ is (in $V$)