MCQ's On Permeability|Absolute And Relative Permeability

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Absolute and Relative Permeabilities of a Medium

The phenomena of magnetism and electromagnetism are dependent upon a certain property of
the medium called its permeability. Every medium is supposed to possess two permeabilities :
(i) absolute permeability (μ) and (ii) relative permeability (μr).
For measuring relative permeability, vacuum or free space is chosen as the reference medium. It
is allotted an absolute permeability of μ0 = 4π × 10−7 henry/metre. Obviously, relative permeability
of vacuum with reference to itself is unity. Hence, for free space,
absolute permeability μ0 = 4π × 10−7 H/m
relative permeability μr = 1.
Now, take any medium other than vacuum. If its relative permeability, as compared to vacuum is
μr, then its absolute permeability is μ = μ0 μr H/m.