Show diagrammatically the behaviour of magnetic field lines in the presence of :
(i) Paramagnetic and
(ii) Diamagnetic substance, How does one explain this distinguishing feature ?

Explanation

(i) The behavior of magnetic field lines in the presence of a paramagnetic substance is shown :

The behavior of magnetic field lines in the presence of a diamagnetic substance is shown :
This distinguishing feature is because of the difference in their relative permeabilities. The relative permeability of the diamagnetic substance is negative: so, the magnetic lines of forces do not prefer passing through the substance. The relative permeability of a paramagnetic substance is greater than 1, so, the magnetic lines of force prefer passing through the substance.