If induction of magnetic field at a point is $B$ and energy density is $U$ then which of the following graphs is correct
The magnetic induction at the centre $O$ in the figure shown is
A charge particle $A$ of charge $q = 2\,\, C$ has velocity $v = 100\,\, m/s.$ When it passes through point Aand has velocity in the direction shown. The strength of magnetic field at point $B$ due to this moving charge is.......$\mu T$ $(r = 2\,\, m).$
If an electron revolves around a nucleus in a circular orbit of radius $R$ with frequency $n$, then the magnetic field produced at the centre of the nucleus will be
Three rings, each having equal radius $R,$ are placed mutually perpendicular to each other and each having its centre at the origin of co-ordinate system. If current $I$ is flowing thriugh each ring then the magnitude of the magnetic field at the common centre is
Magnetic field at the centre $O$ due to the given structure is