CLASSIFICATION OF MAGNETIC SUBSTANCES

CLASSIFICATOIN OF

MAGNETIC SUBSTANCS

ALL THE SUBSTANCES ARE CLASSIFIED INTO THREE TYPES BASED ON THEIR MAGNETIC PROPERTIES. THEY ARE 1. DIA, 2. PARA AND 3. FERRO MAGNETIC SUBSTANCE

1 Dia substances are repelled

by the magnet.

Para substances are feebly attracted by the magnet.

Ferro substances are strongly attracted by the magnet

2 Example of dia substances: Bi, Zn, Ag, Cu, Au .

Example of para substances Al, Pt, Mn, CuCl2,O2.

Example of ferro magnetic substances : Fe,Co, Fe2O4,Ni

3 Susceptibility of dia substances is negative.

Susceptibility of para magnetic substances is positive, low.

Susceptibility of ferro substances is positive , high

4 Permeability of dia magnetic substances is less than 1.

Permeability of para magnetic substances is greater than1

Permeability of ferro magnetic substances is greater than1

5. When a dia substance is placed in the form of liquid in a non- uniform external field, it moves from stronger part towards weaker part.

When a para substance is placed in a non-uniform external field,it moves from edges part towards poles.

When a Ferro substance in the form of liquid is placed in a

non-uniform external field,it moves towards poles.

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