How can you know the magnetic field strength of a magnet?

A magnetic field is a forced space created by the magnet around it due to its electric charges.

Magnetic fields can be grouped into classes depending on the source of creation:

• Magnet magnetic fields: this type of magnetic field is originated naturally as a consequence of spin, in other words, the movement of electrons around the atomic nucleus and the axis.

• Current magnetic fields: this type of magnetic field creation is based on the charges produced by the activity of the electric current. This type of magnetic field is characteristic of electromagnets.

Magnetic fields can be illustrated in two ways:

Vector field: this type of representation of the magnetic field is formed by several vectors that lie within a square. In the vector field, each vector is directed in the same direction in which a compass would point it.

Field lines: this other type of magnetic field representation does not require any squares. In addition, the vector lines are connected to thin lines.

What is magnetic field strength?

Magnetic field strength refers to the magnitude of magnetic forces, which encompasses two factors:

• Magnetic excitation or also known as H-field: is the magnetic field strength that establishes the connection of the magnetic field with the corresponding electrical sources.

• Magnetic induction or also known as B-field: is the magnetic field strength that is focused in the field depending on the effects of electric charges.

To measure the magnetic field strength, a magnetometer is needed, for instance, an instrument by means of which we can measure the strength and direction of the magnetic field.

The intensity of the magnetic field (H) in a coil depends on the magnetomotive force (N-I). It can be known by Faraday's law is known by the formula:

H = (N·I)/l

N = turn of a propeller

I = field current

l = coil length

As the magnetic field lines are farther apart, a longer coil length will be needed and a weaker intensity will be obtained. To achieve a constant magnetomotive force, the field strength must be inversely proportional to the average length of the lines in the magnetic field.