
Physical and Electrical Background
49
μ
0
being the absolute magnetic permeability of the empty space a universal con-
stant equal to 4π* 10
-7
[Tm/A], and μ
r
the relative magnetic permeability,itsvalue
depending on the material.
In SI units
is Tesla,
T
(Nikola Tesla, Croatian-born Serbian-American inven-
tor, 1856 –1943).
The presence of a strong permeability means the material is made of some-
thing that can align strongly to an external magnetic eld. To understand how the
same vector
can produce different results in different materials, we consider
two materials that are diamagnetic and paramagnetic (Figure 2.29).
Diamagnetic materials a ...