Give similarity between Biot-Savart law and electrostatic law of Coulomb.
A uniform wire is bent in the form of a circle of radius $R$. A current $I$ enters at $A$ and leaves at $C$ as shown in the figure :If the length $ABC$ is half of the length $ADC,$ the magnetic field at the centre $O$ will be
The current of $1\,A$ is passed through a hexagonal conducting wire of side $1\,m$ . The magnetic induction at its centre $O$ in $Wb/m^2$ will be
Magnetic field at the centre $O$ due to the given structure is
A beam of neutrons performs circular motion of radius, $r=1 \,m$. Under the influence of an inhomogeneous magnetic field with inhomogeneity extending over $\Delta r=0.01 \,m$. The speed of the neutrons is $54 \,m / s$. The mass and magnetic moment of the neutrons respectively are $1.67 \times 10^{-27} \,kg$ and $9.67 \times 10^{-27} \,J / T$. The average variation of the magnetic field over $\Delta r$ is approximately ....... $T$