Magnetisation And Magentic Intensity - Practice Questions & MCQ

 The magnetic intensity (H)-

The magnetic intensity of the magnetizing field is given by     

 And its S.I. unit is A/m while its C.G.S. Unit is oersted.

Magnetization (M) -

Magnetization is a process in which a normal material is converted into a magnetic material by exposing it to an external magnetic field. The magnetic intensity is the reason due to which a normal material changes into magnetic material.

We define magnetization M of a sample to be equal to its net magnetic moment per unit volume i.e 

Consider a long solenoid of n turns per unit length and carrying a current i 

The magnetic field in the interior of the solenoid is given by 

If  then  where N=number of turns and L=length of solenoid

Using    So we can write 

If the interior of the solenoid is filled with a material with non-zero magnetization then the material will magnetize.

And the field inside the solenoid will be greater than B₀.

The net B field in the interior of the solenoid may be expressed as

B - total magnetic field

 - the magnetic field in a vacuum

 - magnetic field due to magnetization of the material

And is proportional to the magnetization M of the material and is expressed as 

And using  we can write 

So we get 

So we get  

The Magnetization (M) of material is influenced by The magnetic intensity (H)

So the relation between M and H is given as 

where  is called magnetic susceptibility. And it is a measure of how a magnetic material responds to an external field.

Using    in    

we get 

where  is called relative magnetic permeability of the substance.

and       is the magnetic permeability of the substance