A circular coil is in $y-z$ plane with centre at the origin. The coil is carrying a constant current. Assuming direction of magnetic field at $x = -25\, cm$ to be positive direction of magnetic field, which of the following graphs shows variation of magnetic field along $x-$ axis
A symmetric star conducting wire loop is carrying a steady state current $\mathrm{I}$ as shown in figure. The distance between the diametrically opposite vertices of the star is $4 a$. The magnitude of the magnetic field at the center of the loop is
A long wire carries a steady current. It is bent into a circle of one turn and the magnetic field at the centre of the coil is $B$. It is then bent into a circular loop of $n$ $turns$. The magnetic field at the centre of the coil will be
Two thick wires and two thin wires, all of the same materials and same length form a square in the three different ways $P$, $Q$ and $R$ as shown in fig with current connection shown, the magnetic field at the centre of the square is zero in cases
$B _{ X }$ and $B _{ Y }$ are the magnetic field at the centre of two coils of two coils $X$ and $Y$ respectively, each carrying equal current. If coil $X$ has $200$ turns and $20 cm$ radius and coil $Y$ has $400$ turns and $20 cm$ radius, the ratio of $B _{ X }$ and $B _{ Y }$ is
The radius of a circular current carrying coil is $R$. At what distance from the centre of the coil on its axis, the intensity of magnetic field will be $\frac{1}{2 \sqrt{2}}$ times that at the centre?