Following properties we discuss in this class:
- Magnetising field
- Magnetic induction
- Magnetising field intensity
- Magnitisation
- Magnetic susceptibility
- Types of Magnetic susceptibility
- Paramagnetic material
- Diamagnetic material
- Ferromagnetic material
1. Magnitising fields
Magnetic material is placed in vacuum it induced the magnetism which is called magnetising field.
Ex: when a solenoid carrying current is placed in a vacuum magnetic field is set up in the solenoid, the field is called magnetising field.
2. Magnetic induction
The total magnetic field inside a magnetic material is the sum of external magnetising field and additional magnetic field produce due to magnetisation of material and its called magnetic induction.
3. Magnetising field intensity
The ability of magnetising field to magnetise a material is called magnetising field intensity or magnetic intensity.
- It is denoted by; H.
4. Magnetisation
The magnetic moment developed per unit volume of a material when placed in a magnetising field is called magnetisation.
5. Magnetic susceptibility
It is defenders the ratio of intensity of magnetization to the magnetising field better reflects a material degrade of sensitivity to the magnetic field.
There are three types of Magnetic susceptibility.
1. Paramagnetic material
They are magnetic material line along the direction of magnetic field these magnetic material have magnetic susceptibility greater than zero and they are temperature dependent and weekly attract by magnet.
- Magnetic susceptibility > 0
- Temperature dependent
- Weakly attract by magnets
- 1.001 < relative permeability < 1.003
- Ex: Alkaline Earth Metals, aluminium, oxygen etc.
2. Diamagnetic material
- Magnetic susceptibility < 0
- Temperature independent
- Strongly repelled by magnets
- Relative permeability = constant
- Align opposite to the direction of magnetic field.
- Ex: gold, tin, mercury etc.
3. Ferromagnetic material
- Highly magnetism in the presence of magnetic field
- Temperature dependent
- Strongly attract by magnets
- 1000 < relative permeability < 10000
- Ex: cobalt, nickel, soft iron etc.