$A$ coil having an inductance of $0.5\, H$ carries a current which is uniformly varying from zero to $10\, A$ in $2\, s$. The $e.m.f.$ (in volts) generated in the coil is

The length of a wire required to make a solenoid of length $l$ and self-induction $L$ is

$A$ copper wire is wound on a wooden frame,whose shape is that of an equilateral triangle. If the linear dimension of each side of the frame is increased by a factor of $3$,keeping the number of turns of the coil per unit length of the frame the same,then the self-inductance of the coil:

Current in a circuit falls from $5.0 \, A$ to $0.0 \, A$ in $0.1 \, s$. If an average $emf$ of $200 \, V$ is induced,give an estimate of the self-inductance of the circuit in $H$.

If in a coil the rate of change of area is $5 \, m^2/ms$ and the current changes from $2 \, A$ to $1 \, A$ in $2 \times 10^{-3} \, s$. If the magnetic field is $1 \, T$,then the self-inductance of the coil is......$H$

The current in a coil changes from $4 \, A$ to $0 \, A$ in $0.1 \, s$. If the average induced $e.m.f.$ is $100 \, V$,what is the self-inductance of the coil in $H$?