define isotropy and anisotropy.

Hi,

In some substances the properties like electrical conductance, refractive index, and thermal expansion are identical in all directions.  This property is called isotropy and the substances showing this property are called isotropic. Amorphous substances are isotropic in nature as in these the regular arrangement of particles is in small region only.

While, in some substances the properties like electrical conductance, refractive index, thermal expansion have different values in different directions.  This property is called anisotropy and the substances showing this property are called anisotropic. Crystalline substances are anisotropic in nature because while making arrangements in different directions, different types of particles fall on the way.

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