The magnetic susceptibility of the oxygen gas at 20°C is 400 π × 10^-11 H/m. The absolute and relative permeabilities are respectively

 

When a magnetic material (say iron) of cross-sectional area A, and relative permeability 𝜇ᵣ is placed in a uniform field of intensity H, two types of lines of induction pass through it: one due to the magnetizing field H and another due to the iron piece itself being magnetized by induction.

Thus total flux density B will be given by

B = μ₀H + I

where,

Now, absolute permeability is given by μ_a

Dividing either side by μ₀, we get the relative permeability.

 

 

 

Then;

and