What is Magnetic Permeability? Definition and Factors Effecting

What is Magnetic Permeability? Definition and Factors Effecting

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What is magnetic permeability? Magnetic permeability definition: is the ability of a material to respond to how much electromagnetic flux it can support to pass through itself within an applied electromagnetic field. Or magnetic permeability definition: is the ability of a magnetic material to support magnetic field development. Magnetic permeability definition in other words, magnetic permeability is the constant in the proportionality between magnetic induction and magnetic field intensity. And also In other word magnetic permeability of a material is the degree of magnetization capability.

The greater the magnetic permeability of the material, the greater the conductivity for magnetic lines of force, and vice versa. The magnetic permeability of a material indicates the ease with which an external magnetic field can create a higher magnetic force of attraction in the material. The SI unit of magnetic permeability is Henry per meter.

What is Magnetic Permeability? Definition and Factors Effecting

Magnetic permeability is expressed in μ that is a Greek Letter. In 1885, Mathematician Oliver Heaviside had termed magnetic permeability as μ.

A material with good magnetic permeability either gets magnetized in the direction of the magnetic field or in opposition to the magnetic field. The magnetic permeability of a vacuum or air is considered the poorest.

Magnetic permeability is not a constant and is influenced by many factors such as temperature, the medium used, humidity and strength of the magnetic field applied. As a result, in engineering applications, magnetic permeability is usually expressed in relative terms rather than in absolute terms. Purified iron and many magnetic alloys have maximum relative magnetic permeability.

In electromagnetism, H is known as the magnetizing force that signifies the ability of magnetic dipole organizations in any material or medium by magnetic field density B. The relation between B and H is directly proportional, i.e. B α H.

Or, B = μH, where, μ is the proportional constant of that material or medium and it is termed as magnetic permeability.

Hence we can write:

So, in other word magnetic permeability is defined as the ratio of magnetic flux density (B) of a material to its electro-magnetizing force (H).

Unit of Electromagnetic Permeability

The unit of Electromagnetic Permeability is Henry/meter or Newton/sq-ampere.

Permeability in Free Space

Permeability in free pace is denoted as μ0. Its value is 4ᴫ × 10-7 H/m. This value of permeability is taken as standard value that is treated as permeability constant.

Permeability of another Medium or Substance

Permeability of another medium or substance is denoted as μ only. Relative permeability is the ratio of permeability of any substance to that of free space and it is denoted as μr, i.e.

So, permeability of any medium or material is:

Factors Effecting on Permeability

As permeability of any material depends on several factors:

  • Humidity
  • Temperature
  • Position in the medium
  • Frequency of the applied field

Classification of Materials as per Permeability

Diamagnetic: μr is less than 1, this material has opposition to external magnetic field. Paramagnetic: μr is near about 1 but not exactly 1, this material is weakly attracted by external magnetic field.

Ferromagnetic: μr is greater than 1, this material is strongly attracted by external magnetic field.

What is Complex form of Permeability?

Complex permeability comes into account for high frequency magnetic field effects. A phase lag is created between H and B.

Magnetic Permeability Conclusion

After going through the above portion of magnetic permeability we can now establish a magnetic permeability definition. I hope you enjoy when reading this article, thank you.