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9 Cards in this Set
- Front
- Back
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What is an electromagnet?
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A coil of wire wrapped around a metal core, such as a iron bar. When an electric current flows through the coil, it creates a magnetic field, which cause particles inside the metal core to line up. The metal core becomes magnetic and when the current stops the metal core is no longer magnetic.
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Who are Michael Faraday and Joseph Henry?
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Scientists from the 1820's and 1830's that made some amazing discoveries about electric currents and magnets.
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What is a loudspeaker?
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-A device that changes electrical energy into sound.
-Used in radios, televisions and headphones. |
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What is an important part of a loudspeaker?
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Electromagnets
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What is a diaphragm?
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-The part of the loudspeaker that vibrates to create sound. (The motion of it produces sound.)
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What is a microphone?
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A device that uses magnets to convert sound into electrical signals.
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How does a microphone work?
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When you speak into the mouthpiece, a diaphragm vibrates and as the diaphragm moves, a magnet generates electrical signals in a wire connected to the diaphragm.
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What relies on electromagnets and has a tiny loudspeaker?
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A telephone.
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What are some examples of the devices you can find electromagnets in? (There are hundreds.)
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Electric guitars, power plant generators, toy train and car motors, transformers, and many common appliances, like doorbells, vacuum cleaners, and dishwashers.
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