define different type of magnetic material
Answers
There are three types of magnetic materials. They are:
Diamagnetic material
Paramagnetic material
Ferromagnetic material
Diamagnetic material
Those substances which are feebly magnetized in the direction opposite to the applied field are called diamagnetic material. Examples of diamagnetic materials are bismuth, copper, water, mercury, alcohol, argon, gold,tin, mercury, antimony etc. The magnetic moment of atoms of a diamagnetic material is zero. They acquire induced dipole moments when the material placed in an external magnetic field. These moments are in opposite in the direction to the applied field.
Some properties
The diamagnetic materials are repelled by magnets.
When a diamagnetic liquid in a watch glass is placed over two closely spaced pole pieces of the magnet, it is depressed at the middle while in the case of pole pieces separated by a distance, it rises at the middle. Similarly, when a diamagnetic liquid is placed in a U-tube and one of the limbs of the tube is placed between the two strong pole pieces of magnet, the liquid depressed at that limb.
The diamagnetic materials move from a stronger to a weaker field.
A diamagnetic rod, freely suspended in a magnetic field, slowly turns to set at right angle to the applied field.
Since magnetized is opposite in direction to an applied field, the diamagnetic materials have the small value for the intensity of magnetization, I.
The materials have always negative magnetic susceptibility, χ=(μr−1)χ=(μr−1) and accounts from -10-6 to -10-5.
These materials are independent of temperature.
Paramagnetic Material
Those materials which are weekly magnetized in the same direction of the applied magnetic field are called paramagnetic material. The examples of paramagnetic materials are aluminum, chromium, oxygen, manganese, alkali, alkaline earth metal etc.
The paramagnetic materials have permanent magnetic moments. These moments interacts weekly with each other and randomly orient in the different direction.
Some Properties
The paramagnetic materials are feebly attracted by magnets.
A paramagnetic rod, freely suspended in a magnetic field, aligns along the field.
The paramagnetic materials are temperature dependent and follow curve law.
The relative permeability is nearly unity than ranges from 1.00001 to 1.003 for common ferromagnetic materials at room temperature. So, the magnetic lines of force inside the material placed in a magnetic field are more than that outside it.
The susceptibility of paramagnetic substances has small positive value.
Ferromagnetic Material
The ferromagnetic materials are highly magnetized in a magnetic field. The examples of ferromagnetic materials are iron, nickel and cobalt, and their alloys such as alnico. Gadolinium and dysprosium are ferromagnetic at low temperature.
Some Properties
Ferromagnetic materials are highly attracted by magnets.
Ferromagnetic materials more from weaker to stronger field.
A ferromagnetic rod, freely suspended in a magnetic field, turns fast to set along the applied field.
The magnetic susceptibility is positive and very high and varies with applied field.
The relative permeability is very high in the order of 1000 to 100,000.
Ferromagnetic dust in a watch glass, placed over two closely spaced pole-pieces of the magnet, increases at the middle, while pole piece is separated by a distance, depresses in the middle.
Domain Theory of Ferro Magnetism