Speaker 1: Welcome to Brainstuff from house stuff works dot com where
Speaker 1: smart happens. Hi Am Marshall Brain with today's question, what
Speaker 1: is the difference between a fluorescent light and a neon light?
Speaker 1: A neon light is the sort of light you see
Speaker 1: used in advertising signs. These signs are made of long,
Speaker 1: narrow glass tubes, and these tubes are often bent into
Speaker 1: all sorts of shapes. The tube of a neon light
Speaker 1: can spell out a word, for example. These tubes emit
Speaker 1: light in different colors. A fluorescent light, on the other hand,
Speaker 1: is most often a long, straight tube that produces white light.
Speaker 1: You see fluorescent lights and offices, stores, and some home fixtures.
Speaker 1: The idea behind a neon light is simple. Inside the
Speaker 1: glass tube, there is a gas like neon, argon or
Speaker 1: crypton at low pressure. At both ends of the tube,
Speaker 1: there are a metal electrodes. When you apply high voltage
Speaker 1: to the electrodes, the neon gas ionizes and electrons flow
Speaker 1: through the gas. These electrons excite the neon atoms and
Speaker 1: cause them to emit light that we see. Neon emits
Speaker 1: red light when energized in this way. Other gases emit
Speaker 1: other colors. A fluorescent light works on a similar idea,
Speaker 1: but it has an extra step. Inside a fluorescent light
Speaker 1: is low pressure mercury vapor. When ionized, mercury vapor emits
Speaker 1: ultraviolet light. Human eyes are not sensitive to ultraviolet light,
Speaker 1: although human skin is. That's how we get sunburns and
Speaker 1: sun tans. Therefore, the inside of a fluorescent light is
Speaker 1: coated with a phosphor. A phosphor is a substance that
Speaker 1: can accept energy in one form and emit energy in
Speaker 1: the form of visible light. In a fluorescent lamp, the
Speaker 1: phosphor accepts the energy of ultra violet photons and emits
Speaker 1: visible photons. The light we see from a fluorescent tube
Speaker 1: is the light given off by this phosphor that coats
Speaker 1: the inside of the tube. The light of a neon
Speaker 1: tube is the colored light that the neon adams give
Speaker 1: off directly. Do you have any ideas or suggestions for
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