Understanding Magnetic Permeability

In summary, the conversation discusses the concept of magnetic permeability and its relationship to the density of magnetic fields. It is explained that materials with higher permeability will have denser magnetic fields than those with lower permeability. The question is asked if adding a lower permeability material to a series magnetic circuit will result in a drop in flux lines. The expert explains that both materials in the series circuit will have magnetic lines of force from north pole to south pole, assisting each other and preventing a drop in flux lines. The conversation also touches on the difference between magnetic field strength and flux density, and how adding a material with lower permeability to a magnetic circuit can decrease the flux density.
  • #1
escape_velocity
44
2
As per some websites that I visited,
"Magnetic Permeability is the ability of a material to support the formation of a magnetic field"
so in materials with higher permeability the magnetic fields should be denser that materials with lower permeability.

Lets say we have a magnetic circuit with a magnetic material of permeability 1000 and there are 500 flux lines passing through it now if I introduce another material into this circuit with permeability 100 so that both magnetic materials are in series circuit.

Would the 500 flux lines still force themselves through this material or would there be a drop in flux lines?
 
Engineering news on Phys.org
  • #2
According to your question i think that if you form series magnetic circuits with the help of the permanent magnet,the magnetic lines of force will be from north pole to south pole.
Thus two magnets which can attract will form the magnetic circuit.So both the magnets will have magnetic lines of force from north pole to south pole,and thus these lines of force assist each other.So there won't be any drop.
 
  • #3
Navin A S said:
According to your question i think that if you form series magnetic circuits with the help of the permanent magnet,the magnetic lines of force will be from north pole to south pole.
Thus two magnets which can attract will form the magnetic circuit.So both the magnets will have magnetic lines of force from north pole to south pole,and thus these lines of force assist each other.So there won't be any drop.

Actually there are 2 circuits to be compared for flux
1. Magnet + Core (Perm = 1000)
2. Magnet + Core (Perm = 1000) + Core (Perm = 100)
 
  • #4
There are two measures of magnetic field. One is magnetic field strength, commonly denoted by H and measured in A/m. The other is magnetic flux density, denoted by B and measured in Tesla. The relationship between them is
B = u uo H
u is the magnetic permeability and u0 is magnetic 'constant'
Magnetic field strength H, is related to the source. In fact, if you integrate H over a closed loop, it equals to the current enclosed by the loop.
Flux density is the quantity that describes things like forces on moving charges, induced voltage when magnetic field changes with time.
Therefore, if you had two cores same dimensions but different permeability, the magnetic field strength would be the same for both of them, but the flux density would be higher for the higher permeability core.
If you have materials with different permeability connected in series, it is the magnetic flux density that is constant across the boundary.
However, the actual field also depends on the length of the magnetic loop and also changes in cross-sectional area of the magnetic circuit. You can search for Kirchoff's law for magnetic circuits for details.

But coming to your question. I presume that the second circuit will have an extra piece of lower permeability inserted into the first one. In that case, the magnetic flux density for the second circuit would be lower. Actually, just making the magnetic circuit longer will decrease the flux density.
 

What is magnetic permeability?

Magnetic permeability is a measure of how easily magnetic flux can pass through a material. It is a physical property that describes the material's ability to be magnetized by an external magnetic field.

How is magnetic permeability measured?

Magnetic permeability is typically measured using a device called a permeameter, which measures the magnetic flux density of a material in response to an applied magnetic field. The ratio of the flux density to the applied field is the magnetic permeability of the material.

What factors affect magnetic permeability?

The main factors that affect magnetic permeability include the type of material, its temperature, and the strength of the applied magnetic field. Materials with high magnetic permeability are typically ferromagnetic or paramagnetic, while materials with low magnetic permeability are typically diamagnetic.

Why is understanding magnetic permeability important?

Understanding magnetic permeability is important for a variety of scientific and technological applications. It is crucial for designing and optimizing electromagnetic devices such as transformers, motors, and generators. It also plays a significant role in fields such as materials science, geophysics, and medical imaging.

Can magnetic permeability be changed?

Yes, the magnetic permeability of a material can be changed by applying an external magnetic field. This process is known as magnetization and can result in the material becoming temporarily or permanently magnetized. However, the change in permeability is not always proportional to the strength of the applied field and depends on the material's properties.

Similar threads

Replies
8
Views
1K
  • Electromagnetism
Replies
2
Views
3K
  • Introductory Physics Homework Help
Replies
4
Views
365
  • Electromagnetism
Replies
25
Views
3K
  • Electromagnetism
2
Replies
43
Views
1K
  • Classical Physics
Replies
24
Views
1K
  • Electromagnetism
Replies
5
Views
329
  • Electrical Engineering
Replies
1
Views
1K
  • Astronomy and Astrophysics
Replies
10
Views
5K
Replies
3
Views
636
Back
Top