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( Vacuum)
A vacuum is a volume of space that is essentially empty of matter, such that its gaseous pressure is much less than atmospheric pressure.[1] The word comes from the Latin term for "empty," but in reality, no volume of space can ever be perfectly empty. A perfect vacuum with a gaseous pressure of absolute zero is a philosophical concept that is never observed in practice. Physicists often discuss ideal test results that would occur in a perfect vacuum, which they simply call "vacuum" or "free space" in this context, and use the term partial vacuum to refer to real vacuum. The Latin term in vacuo is also used to describe an object as being in what would otherwise be a vacuum. The quality of a vacuum refers to how closely it approaches a perfect vacuum. The residual gas pressure is the primary indicator of quality, and is most commonly measured in units called torr, even in metric contexts. Lower pressures indicate higher quality, although other variables must also be taken into account. Quantum theory sets limits for the best possible quality of vacuum, predicting that no volume of space can be perfectly empty. Outer space is a natural high quality vacuum, mostly of much higher quality than can be created artificially with current technology. Low quality artificial vacuums have been used for suction for many years. Vacuum has been a frequent topic of philosophical debate since Ancient Greek times, but was not studied empirically until the 17th century. Evangelista Torricelli produced the first laboratory vacuum in 1643, and other experimental techniques were developed as a result of his theories of atmospheric pressure. Vacuum became a valuable industrial tool in the 20th century with the introduction of incandescent light bulbs and vacuum tubes, and a wide array of vacuum technology has since become available. The recent development of human spaceflight has raised interest in the impact of vacuum on human health, and on life forms in general. From Latin vacuum (an empty space, void) noun use of neuter of vacuus (empty) related to vacare (be empty).
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Vacuum Subcategories
Vacuum Articles
When the Law of Attraction ISN'T Working: How to Break Through Self-Sabotage by Sonia Miller
The Universe Loves a Vacuum You’ve probably heard people say, “The Universe abhors a vacuum.” Well, I’ve come to know that the Universe actually loves a vacuum. This is because the Universe is about expansion and the vacuum gi...
Vacuuming Boosts Health ? If you Believe It by Simon Evans
unicopia@comcast.net.
Best regards
Simon Evans
http://www.thebraincode.com Vacuuming Boosts Health ? If you Believe It
If you have a career that requires some physical labor,
realize that you are getting some exercise and feel g...
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