Editing Suction (section)

{{short description|Air pressure differential between two areas}}
{{other uses|suction (medicine)|suction convention}}

{{Multiple issues|
{{More citations needed|date=January 2024}}
{{Original research|date=December 2022}}
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[[File:Suction vs Blowing.png|thumb|240x240px|Gasses or liquids that move along a pressure gradient can exert forces on objects. Objects can only be pushed by gases or liquids. The correct terminology used depends on whether they are pushed from a pressurized zone towards ambient pressure (blown out) or from ambient pressure towards a low pressure zone (sucked in). Gases and liquids cannot generate pulling forces on objects.<ref>{{Cite web |last=Quora |title=There's No Suction In Space, Because Suction Is An Illusion |url=https://www.forbes.com/sites/quora/2016/11/21/theres-no-suction-in-space-because-suction-is-an-illusion/ |access-date=2024-01-16 |website=Forbes |language=en}}</ref>]]
'''Suction''' is the day-to-day term for the movement of [[gas]]es or [[liquid]]s along a [[pressure]] gradient with the implication that the movement occurs because the lower pressure pulls the gas or liquid. However, the forces acting in this case do not originate from just the lower pressure side, but also from the side of the higher pressure, as a reaction to the pressure difference.

When the pressure in one part of a [[physical system]] is reduced relative to another, the [[fluid]] or gas in the higher pressure region will exert a [[force]] relative to the region of lowered pressure, referred to as [[pressure-gradient force]]. If all gas or fluid is removed the result is a perfect vacuum in which the pressure is zero. Hence, no negative pressure forces can be generated. Accordingly, from a physics point of view, the objects are not  pulled but pushed.