
Electrical and electronic principles
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• High resistance. This means a part of the circuit has developed a high
resistance (such as a dirty connection), which will reduce the amount of
current that can ow.
1.2.6 Conductors, insulators and
semiconductors
All metals are conductors. Silver, copper and aluminium are among the best
and are frequently used. Liquids that will conduct an electric current are
called electrolytes. Insulators are generally non-metallic and include rubber,
porcelain, glass, plastics, cotton, silk, wax paper and some liquids. Some
materials can act as either insulators or conductors depending on conditions.
These are called ...