Define and Describe on Magnetic Permeability

Magnetic permeability is the ability of the material to allow the passage of magnetic lines of force through it.

Relative permeability μ_r of a material is defined as the ratio of the number of magnetic lines of force per unit area B inside the material to the number of lines of force per unit area in vacuum B₀ produced by the same magnetizing field.

so, Relative permeability μ_r = B/B₀

μ_r = μH/μ₀H = μ/μ₀

(since μr is the ratio of two identical quantities, it has no unit.)

The magnetic permeability of the medium, μ = μ₀ μ_r where μ₀ is the permeability of free space.

Magnetic permeability μ of a medium is also defined as the ratio of magnetic induction B inside the medium to the magnetizing field H inside the same medium.

so, μ = B/H