A short bar magnet of magnetic moment 0.4 J T^$$-$$1 is placed in a uniform magnetic field of 0.16 T. The magnet is in stable equilibrium when the potential energy is

There are four light-weight-rod samples A, B, C, D separately suspended by threads. A bar magnet is slowly brought near each sample and the following observations are noted
(i)  A is feebly repelled
(ii)  B is feebly attracted
(iii)  C is strongly attracted
(iv)  D remains unaffected

Which one of the following is true ?

Two identical bar magnets are fixed with their centers at a distance d apart. A stationary charge Q is placed at P in between the gap of the two magnets at a distance D from the centre O as shown in the figure


The force on the charge Q is

The magnetic moment of a diamagnetic action is