How To Calculate Magnetization

Magnetization is a measure of the density of magnetism and may be calculated from the number of magnetic moments in a given volume. Magnetic moment is a measure of the direction and strength of a magnetic field. Physicists treat magnetic moment as a vector, a quantity that has both magnitude and direction. We can express magnetization in a variety of ways, depending on what we know about the magnetic field.

Step 1

Describe the magnetic moment mathematically. It can be shown as Nm where N is the quantity of the magnetic moment and m is a unit vector that shows the direction of the magnetism. Magnetic moment is measured in area x current, typically square meters amperes (m^2A).

Step 2

Define magnetization mathematically. This may be shown as M = Nm/V where M is the magnetization, N is the quantity of the magnetic moment, m is its direction and V is the volume of the sample.

Step 3

Calculate the magnetism in terms of the magnetic fields. The B-field is the fundamental quantity of a magnetic field and the H-field is a derived field that is defined as H = B/uo -M where uo is the magnetic constant. Therefore, M = B/uo – H.

Step 4

Define dimagnets and paramagnets. A dimagnet is a magnet that exerts a magnetic field in opposition to an externally applied field and a paramagnet exerts a magnetic field that attracts an externally applied field.

Step 5

Show the value for M when the relationship between M and H is linear. This is usually the case with dimagnents and paramagnets and may be shown as M = xmH where xm is the volume magnetic susceptibility, the degree to which the magnetization of a material responds to an external magnetic field.