If X stands for the magnetic susceptibility of a given material, identify the class of materials for which
(i)` -1 le X lt 0`,(ii) `0 lt X lt epsi` (`epsi` stands for a small positive number).
(a) Write the range of relative magnetic permeability of these materials.
(b) Draw the pattern of the magnetic field lines when these materials are placed in an external magnetic field.

Explanation

(i) Material for which `-1 le X lt 0` is a diamagnetic material
(ii) Material having `0 lt X lt epsi` is a paramagnetic material.
(a) Relative magnetic permeability `mu_r =1 + X`. Hence, for diamagnetic materials `0 le mu_r lt 1` and for paramagnetic materials `1lt xlt (epsi + 1)`.
(b) Pattern of magnetic field lines for dia-and paramagnetic materials .