Matching:

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Matching 1. Insulator 2. Positive 3. Ion 4.
Negative 5. Conductor 6. Electricity
A. The charge that attracts electrons. B. An atom
with a different number of electrons than
protons. C. A material that allows the flow
of electricity. D. The caused by the flow of
electrons. E. The charge that attracts
protons. F. A material that resists electricity.
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Conductors and Insulators
Conductivity is the ability or power to conduct
or transmit heat, electricity, or
sound. Conductors are materials that electricity
easily passes through, that do not resist the
flow of electricity. Examples are copper,
aluminum, steel, silver, gold, electrolytes. Not
all materials conduct electricity equally well.

Conductors Allow charge to move readily though
it.
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Insulators Restrict the movement of the charge
? Insulators are materials that resist the flow
of electricity, so electricity does not
easily pass through. Examples are plastic, wood,
rubber, cloth, air, glass. Some materials are
better electricity insulators than others.
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• Semi Conductors

Metals tend to be good conductors of electricity
because they usually have "free electrons" that
can move easily between atoms, and electricity
involves the flow of electrons. Silicon
crystals look metallic, they are not, in fact,
metals. All of the outer electrons in a silicon
crystal are involved in perfect covalent bonds,
so they can't move around. A pure silicon crystal
is nearly an insulator -- very little electricity
will flow through it.
You can change the behavior of silicon and turn
it into a conductor by doping it. In doping, you
mix a small amount of an impurity into the
silicon crystal giving it Semi-conductor
properties.

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Clockwise from top A chip, an LED and a
transistor are all made from semiconductor
material.
A diode is the simplest possible semiconductor
device. A diode allows current to flow in one
direction but not the other.
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A strong superconductor-derived magnetic field
into the body, hydrogen atoms that exist in the
body's water and fat molecules are forced to
accept energy from the magnetic field. They then
release this energy at a frequency that can be
detected and displayed graphically by a computer.
Magnetic Resonance Imaging (MRI)
Magnetic-levitation is an application where
superconductors perform extremely well. Transport
vehicles such as trains can be made to "float" on
strong superconducting magnets, virtually
eliminating friction between the train and its
tracks.