A bar magnet of magnetic moment $M$ is bent into a semicircle. The new magnetic moment is:

Two identical short bar magnets, each having magnetic moment $M$, are placed a distance of $2d$ apart with axes perpendicular to each other in a horizontal plane. The magnetic induction at a point midway between them is

A magnet of magnetic moment $50\,\hat i\,A{m^2}$ is placed in magnetic field $\vec B = \left( {0.5\,\hat i + 0.3\,\,\hat i} \right)T$. Torque acting on the magnet is

$P$ and $Q$ are two unlike magnetic poles. Induction due to '$P$ at the location of '$Q$' is B. and induction due to '$Q$' at the location of $P$is $B/2$. The ratio of poles strengths of ${\rm{P}}\,{\rm{and}}\,{\rm{Q}}$ is

The magnetic field due to short bar magnet of magnetic dipole moment $M$ and length $2l,$ on the axis at a distance $z$ (where $z\; > > l$) from the center of the magnet is given by formula

The magnetic induction field strength at a distance $0.2\,m$  on the axial line of a short bar magnet of moment $3.6\,A{m^2}$ is

A short bar magnet of magnetic moment $M$ is placed in a non-uniform magnetic field $B$. If the gradient of the field is $\frac{dB}{dx}$ along the axis of the magnet, the force on the magnet is:

The length of a magnet of moment $5\,A{m^2}$ is $14\,cm$. The magnetic induction of a point, equidistance from both the poles is {\rm{3}}.{\rm{2}}{\mkern 1mu}  imes {\mkern 1mu} {\rm{1}}{{\rm{0}}^{ - 5}}\,\,{\rm{wb/}}{{\rm{m}}^2}. The distance of the point from either pole is.

The points $A\;{\rm{and}}\;B$ are situated perpendicular to the axis of 2 cm long bar magnet at large distances $x$ and 3$x$ from the centre on opposite sides. The ratio of magnetic fields at $A\;{\rm{and}}\;B$ will be approximately equal to

A magnetic dipole of moment $M$ is aligned at an angle $heta$ with a uniform magnetic field $B$. The work done in rotating it by an angle $dheta$ is:

The magnetic field due to a short magnet at a point on its axis at distance $X\;cm$ from the middle point of the magnet is $200\;gauss$. The magnetic field at a point on the neutral axis at a distance $X\;cm$ from the middle of the magnet is