Intensity of Magnetization Made Simple

 Intensity of magnetization, relation between B, H, and M, 

Magnetization is the measure of the density of permanent or induced dipole moment in a given magnetic material. It is a vector quantity that results from the magnetic moment, which is caused by the motion of electrons in the atoms or the spin of electrons. The intensity of magnetization, denoted by M, is the magnetic moment per unit volume.

The magnetic field inside a material can be described by two vectors: magnetic induction (B) and magnetic field intensity (H). B is the magnetic field strength in a material due to the magnetic field induced by external sources, while H is the magnetic field strength generated by the material itself in response to an external magnetic field. The relationship between B, H, and M is given by the following equations:

B = μ0(H + M)  -----------  (1)

H = (B/μ0) - M  ----------- (2)

M = χmH           ----------- (3)

where μ0 is the permeability of free space, and χm is the magnetic susceptibility of the material.

The role of magnetization in Maxwell's equations is to describe the behavior of magnetic fields (B, H), electric fields (E, D), charge density (ρ), and current density (J).

Units of Intensity of Magnetization

The intensity of magnetization, M, is measured in amperes per meter (A/m) in SI units. Another fundamental quantity is the ratio of magnetization to magnetic field, which is called the susceptibility, χm, and has no units.

In summary, the intensity of magnetization, M, is the magnetic moment per unit volume, and it is related to the magnetic field strength inside a material, which is described by the vectors B and H. The relationship between B, H, and M is given by equations (1)-(3) above, where μ0 is the permeability of free space, and χm is the magnetic susceptibility of the material. The intensity of magnetization is measured in amperes per meter (A/m) in SI units, while the susceptibility has no units.

In case of bar magnet

For a bar magnet, the magnetization can be illustrated as follows:

When a bar magnet is placed in an external magnetic field, it becomes magnetized. The magnetization is represented by the magnetic dipole moment (m) of the magnet, which is a vector quantity that points from the south pole to the north pole of the magnet.

The magnetization of the bar magnet can be visualized as a collection of tiny magnetic dipoles, each of which contributes to the overall magnetic moment of the magnet. These dipoles are aligned with each other, and with the direction of the magnetic field, to produce a net magnetic moment for the entire magnet.

The intensity of magnetization of the bar magnet can be defined as the magnetic moment per unit volume of the magnet. It is a measure of the degree to which the magnet is magnetized, and depends on the strength of the external magnetic field and the properties of the material of the magnet.

The magnetic field produced by the bar magnet can be represented by magnetic field lines that extend from the north pole to the south pole of the magnet. The direction of the field lines is from the north pole to the south pole outside the magnet, and from the south pole to the north pole inside the magnet.

The relationship between magnetic field strength, magnetic flux density, and intensity of magnetization for a bar magnet can be described by the equations B = μ0(H + M) and M = χm(H), where B is the magnetic flux density, H is the magnetic field strength, μ0 is the vacuum permeability, and χm is the magnetic susceptibility of the material.

In summary, a bar magnet can be visualized as a collection of tiny magnetic dipoles that are aligned with each other and with the external magnetic field to produce a net magnetic moment for the entire magnet. The intensity of magnetization is a measure of the degree to which the magnet is magnetized and depends on the properties of the material and the strength of the external magnetic field. The magnetic field produced by the magnet can be represented by magnetic field lines that extend from the north pole to the south pole of the magnet.

Frequently Asked Questions – FAQs

⇒ What is the difference between magnetic field strength and magnetic flux density?

Magnetic field strength is the measure of the magnetic field produced by a magnetic source such as a magnet or a current-carrying wire. It is measured in units of amperes per meter (A/m). Magnetic flux density, on the other hand, is the measure of the magnetic field strength at a particular point in space. It is measured in units of tesla (T).

⇒ What is the relationship between magnetic field and electric current?

Magnetic field is produced by moving electric charges, such as those in an electric current. The direction of the magnetic field is perpendicular to the direction of the current flow. The strength of the magnetic field is directly proportional to the current flowing through the wire.

⇒ What is the right-hand rule for magnetic fields?

The right-hand rule is used to determine the direction of the magnetic field produced by a current-carrying wire. If the thumb of the right hand points in the direction of the current flow, then the fingers will curl around in the direction of the magnetic field.

⇒ What is magnetic induction?

Magnetic induction is the process by which a material becomes magnetized when placed in an external magnetic field. The magnetic field induces a magnetic moment in the material, resulting in a net magnetic field.

⇒ What is magnetic permeability?

Magnetic permeability is a measure of a material's ability to conduct magnetic flux. It is a property of the material and is defined as the ratio of magnetic flux density to magnetic field strength. Materials with high magnetic permeability are called ferromagnetic and are used in applications such as electromagnets and transformers.

⇒ What is the difference between diamagnetism and paramagnetism?

Diamagnetic materials are those that have no permanent magnetic moment and are not attracted to magnetic fields. Paramagnetic materials have a weak, temporary magnetic moment and are attracted to magnetic fields.

⇒ What is hysteresis?

Hysteresis is the phenomenon where the magnetic properties of a material depend on its past magnetic history. In other words, the magnetic field required to magnetize a material depends on the magnetic field to which it was previously exposed.

⇒ What is magnetic shielding?

Magnetic shielding is a technique used to reduce the magnetic field in a particular region by surrounding it with a material that has high magnetic permeability. This can be used to protect sensitive equipment from external magnetic fields, or to prevent magnetic fields from interfering with other systems.

Let me know if you have more questions or if there is a specific topic that you would like to know more about.