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Unity

• The unification of distinct areas of physics leads to an explosion in the growth of knowledge and understanding

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Why does a compass needle always point north?

A) Because it helps sailors find the north when the stars are not visible.

B) Because it is the finger of God

C) Because north is one of the true directions of nature.

D) Because the earth behaves like a bar magnet.

E) Because there is a huge magnetic mountain at the North Pole

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Gilbert’s Breakthrough:The earth is a magnet

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Gilbert Demonstrating Electricity to Queen Elizabeth

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Frictional ElectricityEarly Experiments With Electric Shocks

Friction Charging machine Spark

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Franklin’s Laboratory Experiments With Electrical Sparks

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Franklin proves that lightning is electrical discharge of a cloud

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And Captures Lightning in a Bottle

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Galvani: Twitching Frogs Galvanize Science

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Volta Demonstrates the Effects of Electrical Current to Napoleon

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Oersted Discovers A Connection Between Electricity and Magnetism (DEMO)

Electric current deflects a magnet

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Ampere Makes a Coil of Current Carrying Wire into a Strong Magnet

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Faraday: Can A Magnet Generate Electrical Current?

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Lines of Force: Magnetic

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Current Carrying Wires and Loops

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Current Carrying Loops Bar Magnet

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When the girl acquires an electric charge, why does her hair stand up?

A) The strands of hair get magnetized and repel each other

B) Her hair dresser put too much jell.

C) She was having a bad hair day.

D) The strands of hair acquire electric charge of the same sign and repel each other.

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Electric Field

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Electric Field Lines of a Di-pole

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Magnetic & Electric Fields

Magnetic Dipole Electric Dipole

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QuickTime™ and aAnimation decompressor

are needed to see this picture.

Oscillating Electric Dipole (Movie)

Oscillating charges generate electromagnetic waves

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QuickTime™ and a decompressor

are needed to see this picture.

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A Unified Theory of Electromagnetic Waves

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Electromagnetic Waves

"I have... an electromagnetic theory of light which ...I hold to be great guns. All the properties of light in solids, crystals, empty space follow without further ado directly from mathematics. And the speed of light is predicted."

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