Calculate torque acting on a bar magnet of length 20 cm magnetic dipole moment `4 xx 10^(-6) Am^(2)` , which is placed in earth's magnetic field of flux density ` 2 xx 10^(-5) T` , perpendicular to the field .

Calculate the torque acting on a magnet of length 20 cm and of pole strength 2 xx 10^(-5) Am , placed in earth's magnetic field of flux density 2 xx 10^(-5) T , when (i) magnet is parallel to the field (ii) magnet is perpendicular to the field .

Magnetic dipole moment of a bar magnet is 3 hat(i) "Am"^(2) and the magnetic field intensity is 2 xx 10^(-5) T in y direction calculate the torque on the magnet.

A magnetised needle of magnetic moment 3.6 xx 10^(-2) T^(-1) is placed at 30^(@) with the direction of uniform magnetic field of magnitude 2 xx 10^(-2)T . Calculate the torque acting on the needle.

A magnetised needle of magnetic moment 4.8xx10^(-2)JT^(-1) is placed at 30^@ with the direction of uniform magnetic field of magnitude 3xx10^(-2)T . Calculate the torque acting on the needle.

Calculate the work done in deflecting a small magnet of magnetic moment 10Am^(2) through 180^(@) from a uniform magnetic field of strength 0.4 xx 10^(-4)T .

A magnetised needle of magnetic moment 4.8 xx 10^-2JT^-1 is placed at 30^@ with the direction of uniform magnetic field of magnitude 3xx10^-2T . Calculate the torque acting on the needle.

The magnitude of earth magnetic field at magnetic equator is 2.8 xx 10^(-5) T . Find magnitude of earth's magnetic field near geomagnetic poles .