How It Works - National Geographic Junior Bedienungsanleitung

How it Works

Metal detectors work on the principles of electromagnetism,
described in the 1860s by physicist James Maxwell in the
mathematical formulas known as "Maxwell's Equations."
Basically it works like this: wherever there is a changing
electrical field, there will be a changing magnetic field,
and wherever there is a changing magnetic field, there
will be a changing electrical field.
A simple metal detector consists
of two coils of wire that produce
Receiver Coil
magnetic fields. The first
coil is at the bottom Transmitter Coil
of the detector—
the sensor—and is
connected to a battery that
supplies electricity. When
the electrical current runs
through this "transmitter
coil" it creates a magnetic
field that moves around
as you move the sensor
over the ground. When
that field moves over a
metallic object, it affects
how the electrons in the
metal's atoms behave,
which induces electrical
activity in the metal. Since
electrical activity is linked
to magnetic activity, the moving
metal detector actually creates a
magnetic field around the metallic object.
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