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

The current in a coil changes from $2 \,A$ to $5 \,A$ in $0.3 \,s$. The magnitude of emf induced in the coil is $1.0 \,V$. The value of self-inductance of the coil is (in $\,mH$)

What length of a very thin wire is required to obtain a solenoid of length $l_0$ and inductance $L$?

$A$ hollow cylinder has length $l$,radius $r$,and thickness $d$,where $l >> r >> d$,and is made of a material with resistivity $\rho$. $A$ time-varying current $I$ flows through the cylinder in the tangential direction. Assume the current is always uniformly distributed along the length of the cylinder. The cylinder is fixed so that it cannot move; assume that there are no externally generated magnetic fields during the time considered for the problems below. Assume current at $t = 0$ to be $I_0$. What is the current $I(t)$ for $t > 0$?

$A$ long solenoid has $1000$ turns. When a current of $4\, A$ flows through it,the magnetic flux linked with each turn of the solenoid is $4 \times 10^{-3}\, Wb$. The self-inductance of the solenoid is......$H$

The self-inductance of a coil having $500$ turns is $50\,mH$. The magnetic flux through the cross-sectional area of the coil when the current through it is $8\,mA$ is found to be: