Three identical specimens of magnetic materials Nickel, Antimony, Aluminium are kept in a uniform magnetic field. Draw the modification in the field lines in each case. Justify your answer.

Figure below shows a small magnetized needle $A$ placed at a point $O$. The arrow shows the direction of its magnetic moment. The other arrows show different positions (and orientations of the magnetic moment) of another identical magnetized needle $B$.

In which configuration is the system in stable equilibrium.

Figure below shows a small magnetized needle $A$ placed at a point $O$. The arrow shows the direction of its magnetic moment. The other arrows show different positions (and orientations of the magnetic moment) of another identical magnetized needle $B$.

In which configuration is the system in unstable equilibrium.

Find Curie constant for chromium potassium alum from its $x$ vs. $1/T$ graph shown in figure below.