Insulators and Conductors
Insulators
Have you ever noticed that your TV power cord is wrapped in rubber or plastic? That
wrapping allows you to touch the cord without getting shocked by current electricity.
Plastic, rubber, glass, and wood are all examples of good
insulators. These materials block the flow of electrons.
Electrons cannot easily move through them. A resistor, such
as the wire inside a light bulb, slows the flow of electrons
down, allowing only some of the electrons to pass.
Conductors
Some materials allow electricity to flow easily across them. They are
like the highways for electrons to speed through. These are called
conductors. Metals such as steel, copper, iron, gold, and silver are
all great conductors.
Travel down most roads and you will see
wires high on top of metal towers. Those long wires carry
electricity from where it is generated to our homes and
schools.