Tečno agregatno stanje – razlika između verzija
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Tečnosti se ponekad koriste u mernim uređajima. [[Termometar|Termometri]]<ref>Middleton, W.E.K. (1966). ''A history of the thermometer and its use in meteorology''. Baltimore: Johns Hopkins Press. Reprinted ed. 2002, ISBN 0-8018-7153-0.</ref> često koriste [[termička dilatacija|termalnu ekspanziju]] tečnosti, kao što je [[živa]], u kombinaciji sa njenom sposobnosti da teče, za indiciranje temperature.<ref>T.D. McGee (1988) ''Principles and Methods of Temperature Measurement'' ISBN 0-471-62767-4</ref><ref>T.D. McGee (1988) ''Principles and Methods of Temperature Measurement'' page 3, ISBN 0-471-62767-4</ref> [[Manometar]] koristi težinu tečnosti kao indikator [[vazdušni pritisak|vazdušnog pritiska]].<ref>Bela G. Liptak [http://books.google.com/books?id=pPMursVsxlMC&pg=PA807 ’’Instrument engineers’ handbook: process control’’] CRC Press 1999 p. 807 ISBN 0-8493-1081-4</ref>
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=== Zapremina ===
[[Zapremina]] date količine tečnosti je fiksna na datoj [[temperatura|temperaturi]] i [[pritisak|pritisku]]. Tečnosti se generalno šire pri zagrevanju, i sakupljaju pri hlađenju. [[Voda]] između 0 °C i 4 °C je primetni izuzetak.
▲Quantities of liquids are commonly measured in units of [[volume]]. These include the [[International System of Units|SI]] unit [[cubic metre]] (m<sup>3</sup>) and its divisions, in particular the cubic decimeter, more commonly called the [[litre]] (1 dm<sup>3</sup> = 1 L = 0.001 m<sup>3</sup>), and the cubic centimetre, also called millilitre (1 cm<sup>3</sup> = 1 mL = 0.001 L = 10<sup>−6</sup> m<sup>3</sup>).
▲Liquids have little [[compressibility]]. Water, for example, will compress by only 46.4 parts per million for every unit increase in atmospheric pressure (bar).<ref>[http://hyperphysics.phy-astr.gsu.edu/hbase/tables/compress.html Compressibility of Liquids]</ref> At around 4000 bar (58,000 psi) of pressure, at room temperature, water only experiences an 11% decrease in volume.<ref name="ReferenceA">''Intelligent Energy Field Manufacturing: Interdisciplinary Process Innovations'' By Wenwu Zhang -- CRC Press 2011 Page 144</ref> In the study of [[fluid dynamics]], liquids are often treated as [[incompressible]], especially when studying [[incompressible flow]]. This incompressible nature makes a liquid suitable for transmitting hydraulic power, because very little of the energy is lost in the form of compression.<ref name="ReferenceA"/> However, the very slight compressibility does lead to other phenomena. The banging of pipes, called [[water hammer]], occurs when a valve is suddenly closed, creating a huge pressure-spike at the valve that travels backward through the system. Another phenomenon caused by liquid's incompressibility is [[cavitation]], where liquid in an area of low pressure vaporizes and forms bubbles, which then collapse as they enter high pressure areas. This causes liquid to fill the cavity left by the bubble with tremendous, localized force, eroding any adjacent solid surface.<ref>''Fluid Mechanics and Hydraulic Machines'' by S. C. Gupta -- Dorling-Kindersley 2006 Page 85</ref>
=== Pritisak i
{{main|Statika fluida}}
U [[gravitaciono polje|gravitacionom polju]], tečnosti vrše [[pritisak]] na zidove suda kao i na predmete u samoj tečnosti. Taj pritisak se prenosi u svim pravcima i povećava se sa dubinom. Ako je tečnost u miru u uniformnom gravitacionom polju, pritisak, ''p'', na bilo kojoj dubini, ''z'', je dat sa
:<math>p=\rho g z\,</math>
gde:
:<math>\rho\,</math>
:<math>g\,</math>
Ova formula pretpostavlja da je pritisak ''na'' slobodnoj površini jednak nuli, i da su efekti [[površinski napon|površinskog napona]] zanemarljivi.
Objekti uronjeni u tečnosti su podložni fenomenu [[potisak|potiska]].<ref>{{Cite web|url=http://www.weizmann.ac.il/home/fnfal/papers/Natfloat.pdf |title=Floater clustering in a standing wave: Capillarity effects drive hydrophilic or hydrophobic particles to congregate at specific points on a wave | date=23 June 2005 |format=PDF}}</ref> (Potisak je primenta u svim fluidima, mada je posebno jak u tečnostima zbog njihove velike gustine.)
=== Površine ===
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