$A$ toroid with thick windings of $N$ turns has inner and outer radii $R_{1}$ and $R_{2}$,respectively. If it carries a steady current $I$,the variation of the magnetic field due to the toroid with radial distance $r$ is correctly graphed in

An infinitely long hollow conducting cylinder with inner radius $R/2$ and outer radius $R$ carries a uniform current density $J$ along its length. The magnitude of the magnetic field,$|\vec{B}|$ as a function of the radial distance $r$ from the axis is best represented by:

The correct curve between the magnetic induction $B$ along the axis of a long solenoid due to current flow $i$ in it and distance $x$ from one end is:

If the number of turns per unit length of a solenoid is doubled, what happens to the magnetic field in the solenoid?

$A$ current of $1/4\pi \ A$ is flowing through a toroid. It has $1000$ turns per meter. The value of the magnetic field (in $Wb/m^2$) along its axis is:

In a current-carrying long solenoid,the magnetic field produced does not depend upon: