20
CONDUCTORS, INSULATORS, SEMICONDUCTORS
Look at the following diagram. Refer to
your background knowledge and clarify what
it shows
Vocabulary Preview
Study the following words and try to use
them in this topic
conductivity – n, [U] the property of
allowing heat or electricity to go through
something:
the change in electrical conductivity
is measured at suitable time intervals.
alloy – n, [C or U] a metal that is made by
mixing two or more metals, or a metal and
another substance:
brass is an alloy of copper
and zine.
property – n, [C] a quality in a substance or
material, especially one that means that it can be
used in a particular way:
one of the properties of
copper is that it conducts heat and electricity
very well.
resistance – n, [C or U] the degree to which
a substance prevents the flow of an electric
current through it:
copper has low resistance.
semiconductor – n, [C] a material, such as silicon, that allows electricity
to move through it more easily when its temperature increases:
semiconductors
are used for making integrated circuits.
Choose the correct option to complete each sentence
1.
The substances that strongly resist the flow of current are termed
semiconductors/ insulators.
2.
Substances through which currents easily pass are known to be
conductors/ semiconductor.
3.
Semiconductors are having a
negative/ positive
temperature
coefficient of resistance.
4.
The electrical conduction inside semiconductors is due to the
movement of
electrons and holes/ charges and holes
.
Fig.4
