WEBVTT - How do neon and fluorescent lights differ?

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<v Speaker 1>Welcome to Brainstuff from house stuff works dot com where

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<v Speaker 1>smart happens. Hi Am Marshall Brain with today's question, what

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<v Speaker 1>is the difference between a fluorescent light and a neon light?

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<v Speaker 1>A neon light is the sort of light you see

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<v Speaker 1>used in advertising signs. These signs are made of long,

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<v Speaker 1>narrow glass tubes, and these tubes are often bent into

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<v Speaker 1>all sorts of shapes. The tube of a neon light

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<v Speaker 1>can spell out a word, for example. These tubes emit

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<v Speaker 1>light in different colors. A fluorescent light, on the other hand,

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<v Speaker 1>is most often a long, straight tube that produces white light.

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<v Speaker 1>You see fluorescent lights and offices, stores, and some home fixtures.

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<v Speaker 1>The idea behind a neon light is simple. Inside the

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<v Speaker 1>glass tube, there is a gas like neon, argon or

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<v Speaker 1>crypton at low pressure. At both ends of the tube,

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<v Speaker 1>there are a metal electrodes. When you apply high voltage

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<v Speaker 1>to the electrodes, the neon gas ionizes and electrons flow

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<v Speaker 1>through the gas. These electrons excite the neon atoms and

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<v Speaker 1>cause them to emit light that we see. Neon emits

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<v Speaker 1>red light when energized in this way. Other gases emit

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<v Speaker 1>other colors. A fluorescent light works on a similar idea,

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<v Speaker 1>but it has an extra step. Inside a fluorescent light

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<v Speaker 1>is low pressure mercury vapor. When ionized, mercury vapor emits

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<v Speaker 1>ultraviolet light. Human eyes are not sensitive to ultraviolet light,

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<v Speaker 1>although human skin is. That's how we get sunburns and

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<v Speaker 1>sun tans. Therefore, the inside of a fluorescent light is

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<v Speaker 1>coated with a phosphor. A phosphor is a substance that

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<v Speaker 1>can accept energy in one form and emit energy in

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<v Speaker 1>the form of visible light. In a fluorescent lamp, the

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<v Speaker 1>phosphor accepts the energy of ultra violet photons and emits

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<v Speaker 1>visible photons. The light we see from a fluorescent tube

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<v Speaker 1>is the light given off by this phosphor that coats

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<v Speaker 1>the inside of the tube. The light of a neon

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<v Speaker 1>tube is the colored light that the neon adams give

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<v Speaker 1>off directly. Do you have any ideas or suggestions for

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