Define magnetic susceptibility of a material. Name two elements, one having positive susceptibility and the other having negative susceptibility . What does negative susceptibility signify ?

Explanation

Magnetic susceptibility:Magnetic susceptibility of material is defined as the ratio of the intensity of magnetisation `(I)`induced in the material to the magnetisation force `(H)` applied on it.
Magnetic susceptibility is represented by `X_(m)=I/H` Diamagnetic substances like copper, lead etc. has negative susceptiblity.
Paramagnetic substance like aluminimum calcuim etc.has positive susceptibility.
Negative susceptibility of diamagnetic substance does not change with temperature.