The diagram shows magnetic field lines. We move from above to below and back.Below shows the graph of variaton of magnetic flux with time. We will measure the flux of

A bar magnet of length $6\,cm$ has a magnetic moment of $4\,J\,T^{-1}$. Find the strength of magnetic field at a distance of $200\,cm$ from the centre of the magnet along its equatorial line.

A bar magnet having centre $O$ has a length of $4 $ $cm. $ Point $P_1$ is in the broad side-on and $P_2 $ is in the end side-on position with $OP_1 = OP_2 = 10$ metres. The ratio of magnetic intensities $H$ at $P_1$ and $P_2$ is

A short bar magnet of magnetic movement $5.25 \times 10^{-2} \;J\, T ^{-1}$ is placed with its axis perpendicular to the earth's field direction. At what distance from the centre of the magnet, the resultant field is inclined at $45^{\circ}$ with earth's field on

$(a)$ its normal bisector and

$(b)$ its axis.

Magnitude of the earth's field at the place is given to be $0.42 \;G$. Ignore the length of the magnet in comparison to the distances involved.

The dipole moment of a short bar magnet is $1.25\, A-m^2$. The magnetic field on its axis at a distance of $0.5$ metre from the centre of the magnet is

Assertion : The poles of magnet can not be separated by breaking into two pieces.

Reason : The magnetic moment will be reduced to half when a magnet is broken into two equal pieces.