Insulators are substances where electrons cannot move freely, causing a charge to build up on their surface. Conductors allow electrons to move freely throughout. Electricians wear insulating clothing to avoid electrocution from conducting electricity. We get more static shocks in winter because dry air is an insulator that does not remove the charges our bodies pick up, resulting in a shock when we touch a conductor like a doorknob. Airplanes are made of both conductors and insulators for safety - the surface is a conductor so lightning can pass through, while the interior uses insulators so electrons cannot reach the passenger cabin.

1. Insulators and Conductors
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2. Insulators and Conductors
Insulators
An electrical insulator is a substance in which
electrons cannot move freely from surface to
surface.
Electricians wear safety
clothing with thick layers of
insulating material to avoid
electrocution.
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3. Insulators and Conductors
Insulators
The charge on the surface of
an insulator stays until it is
grounded or neutralized.
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4. Holding a charge
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5. Insulators and Conductors
Insulators
A positive or a negative charge can build up on an
insulator.
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6. Insulators and Conductors
Conductors
An electrical conductor is a substance in which
electrons move freely throughout.
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7. Insulators and Conductors
Conductors
Solid conductors are usually metals.
Most aqueous solutions are conductors.
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8. Freely moving charge
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9. Insulators and Conductors
Why do we get more static shocks in the
winter than in the summer?
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10. Insulators and Conductors
Because winter air is dryer than in the
summer and dry air is an insulator.
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11. Insulators and Conductors
So the winter air does not remove any of the
charges our bodies pick up.
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12. Insulators and Conductors
Then when we touch another conductor (like
a doorknob) we receive a shock as electrons
pass through our hand and the doorknob.
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13. Insulators and Conductors
Airplanes are made of conductors and insulators to
ensure safety if struck by lightening
Lightening striking 747 (@ 26:00)
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14. Insulators and Conductors
The airplane surface is made of a conductor so that
electrons can pass through.
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15. Insulators and Conductors
The airplane surface is made of a conductor so that
electrons can pass through.
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16. Insulators and Conductors
The airplane interior is made of insulators so that the
electrons cannot pass through to the passenger cabin
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17. Insulators and Conductors
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