Magnet :
A piece of substance when attracts small pieces of iron and towards north south directions when suspended freely is called magnet.
Magnetism :
The power of attracting small pieces of iron is magnetism.
The region or space around a magnet in which it can exert its magnetic force on other magnet is called magnetic field.
Magnetic lines of force :
The path along which an isolated north pole move in a magnetic field is called magnetic lines of force. It is the part of north poles of magnetic lines of force always start.
Type of magnetic material :
There are two types of magnetic material.
Soft Magnetic Material :
The material which can be easily magnetized by an external magnetic field are called soft magnetic material. The magnetism of soft magnetic material is temporary and is removed if external field is removed.
Hard Magnetic Material :
The material which can be magnetized only if the external magnetic field is very strong is called hard magnetic material. They are magnetism is permanent and it is not removed by removing the external field.
Non-magnetic material :
The material which do not give any response to the external magnetic field are called non-magnetic material. Example of non magnetic material wood, glass and polymers etc.
Example of magnetic material iron Nickel Cobalt etc.
Classification of Magnetic Material on the basis of their properties :
The magnetic material are divided into three classes on the basis of their property :
Peramagnetic Material :
Material which are attracted by other magnets are called peramagnetic material .
For example aluminium , magnesium , Platinum, Crown glass and solution of salt of iron and oxygen.
Properties of peramagnetic material :
Following are the properties of peramagnetic material.
- They move from weaker to set stronger part of magnetic field when their place in external magnetic field.
- They are magnetic character is dependent of temperature.
- The align themselves parallel to the external magnetic field then place in the external field.
- Its magnetic susceptibility is greater than one.
- Unpaired electrons are present in it.
- Their relative permeability is greater than 1.
