Relative magnetic permeability of diamagnetic materials is always less than unity that is μr < 1 Explanation:
Relative magnetic permeability is defined as the ratio of permeability of medium (μ) to the permeability of free space (μ0) μr = μ/μ0 or μr
Magnetic permeability is defined as the degree to which the magnetic lines of force can penetrate or permeate the material. It can also be defined