A magnetic field is an invisible force field created by a magnet or as a
consequence of the movement of electric charges (flow of electricity).
The magnitude (intensity) of a magnetic field is usually measured
Tesla (T or in mT), but it can also be measured in
Gauss (G).
The intensity of the field decreases with distance from the field source.
Source: GreenFacts
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Static magnetic fields are magnetic fields that do not vary
with time (frequency of 0 Hz).
They are created by a magnet or by the steady flow of electricity, for example
in appliances using direct current (DC).
They are different from fields that change over time, such as electromagnetic
fields generated by appliances using alternating current (AC) or by cell phones
etc.
