Electromagnetism

Electromagnetism is generated by an electric current. In essence, all magnetism is caused by either rotating or revolving electrical charges in eddy currents.

Physics of electromagnetism

A magnetic field is generated around a conductive wire through which an electric current flows. The generated magnetic flux density B is expressed in tesla (T), gauss (G = Vs/m2) or weber (Wb/m2):

Φ = L * I
B = ΔΦ/ΔS, with ΔS as surface[m2].

where:

Φ is the magnetic flux expressed in weber (Wb)
L is the self-induction in henry (H)
I is the current in ampere (A)

We get a strong magnetic field from high currents or high self-induction. High currents are not always applicable or desirable; they can be dangerous and generate heat. That is why we usually generate a high self-induction by winding a wire around an iron core, which is referred to as a ‘solenoid’. The fields generated with each winding act collectively, resulting in a strong and harmless magnetic field.

Goudsmit Magnetics supplies various industrial magnet systems that make use of electromagnetism. See also our industry pages for the right magnetic solution for your problem or application.