Magnetic properties of matter are their macroscopic behaviour in a magnetic field under varying conditions ; These are : permeability ,susceptibility, hysteresis retentivity and coercivity. Permeability : Suppose that a long unmagnetised bar of a substance is placed in a uniform magnetic field of induction B0. Before the specimen is introduced into the field it is represented by a set of parallel lines known as lines of inducton.

1. MAGNETISM
Presented By
Asst. Prof. Amresh Chandra Pandey

2. Magnetic properties of matter
Magnetic properties of matter are their
macroscopic behaviour in a magnetic
field under varying conditions ; These
are : permeability ,susceptibility,
hysteresis retentivity and coercivity.

3.  Permeability : Suppose that a long unmagnetised
bar of a substance is placed in a uniform magnetic
field of induction B0. Before the specimen is
introduced into the field it is represented by a set
of parallel lines known as lines of inducton.

4. Figure(1)

5. Figure(2)

6.  Figure(3)

7. When the specimen is introduced the lines of
induction are distributed as shown in fig -2.
We have shown in figure the general behaviour of
magnetic substance.We observed that the lines of
induction are crowded inside or outside in magnetic
material.

8. Thus we see that different magnetic substance are
penetrable to a magnetic field to different extant.
So we can say that , the property of a magnetic
substance representing the extent to which it is
penetrable to the external magnetic field is called its
permeability.

9. Mathematically, the ratio of magnetic induction B in
the material to the field intensity vector H is called
permeability.
It is generally denoted by(µ).
µ = B/H

10. Susceptibility : When two identical specimen of the
same volume and size but of different material are
placed turn by turn , in the magnetic field of the same
intensity vector (H). It is found that they have been
magnetised to different extents.

11. This property representing the extent to which a magnetic
substance is magnetisable is called its susceptibility.
Mathematically,
The ratio of magnetisation to the intensity vector of
applied field is called magnetisation.
That is ,
ᵪ = M/H
 Hysteresis
The lagging of Magnetic induction B behind intensity
vector H is called hysteresis.

12. FERRIMAGNETISM
antifrromamagnetism Ferromagnet
magnetic domain