# Magnetic Permeability: Definition and Factors Effecting

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What is magnetic permeability? Magnetic permeability 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 is the ability of a magnetic material to support magnetic field development. 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 demonstrates the ease with which an external magnetic field can make a higher magnetic force of fascination in the material. The SI unit of magnetic permeability is Henry per meter.

# 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 certainly not a consistent and is impacted by numerous elements, such as temperature, the medium used, humidity and strength of the magnetic field connected. 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 corresponding consistent of that material or medium and it is named 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 penetrability is the proportion of permeability of any substance to that of free space and it is signified 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 close around 1 but not actually 1, this material is pitifully pulled in by external magnetic field.

Ferromagnetic: μr is greater than 1, this material is unequivocally pulled in by external magnetic field.

## What is Complex form of Permeability?

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