Q.
The variation of the intensity of magnetisation (I) with respect to the magnetising field (H) is a diamagnetic substance is described by the graph :-
Intensity of magnetization I=χH where χ is the magnetic susceptibility
For diamagnetic substances, χ is negative but has magnitude very very small than 1 .
Slope of I Vs H graph for diamagnetic substance is very small in magnitude but negative.