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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