- Ram pressure
In
physics , ram pressure is a pressure exerted on a body which is moving through afluid medium. It causes a strong drag force to be exerted on the body.For example, a
meteor traveling through the Earth's atmosphere produces ashock wave generated by the extremely rapid compression of air in front of the meteoroid. It is primarily this ram pressure (rather thanfriction ) which heats the air which in turn heats the meteoroid as it flows around it. [Plait, p.1]In the case of a
galaxy moving through theintergalactic gas , the ram pressure is capable of stripping the galaxy of much of itsinterstellar gas . [ Grebel, Gallagher, Harbeck, pp.1-15]The ram pressure increases when the velocity increases. For example, when you are in a windy place, you feel a force on your body from the wind. The stronger (faster) the wind, the greater the force you feel.
Notes
References
*Grebel, Gallagher, Harbeck (2003) [http://arxiv.org/abs/astro-ph/0301025 "The Progenitors of Dwarf Spheroidal Galaxies" ] ArXiv.org. retrieved Nov. 2007
*Plait, Philip (2002), Top 5 Cosmic Myths #4: [http://www.space.com/scienceastronomy/top5_myths_020903-4.html "Meteors are heated by friction as they pass through the atmosphere"] . Space.com. re-retrieved Nov. 2007External links
[http://arxiv.org/abs/physics/0609156 Educational materials on air resistance]
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