fluid pressure
Learn about this topic in these articles:
major reference
- In fluid mechanics: Basic properties of fluids
…arises when adjacent layers of fluid slip over one another. It follows that the shear stresses are everywhere zero in a fluid at rest and in equilibrium, and from this it follows that the pressure (that is, force per unit area) acting perpendicular to all planes in the fluid is…
Read More - In fluid mechanics: Convection
Consequently, the vertical pressure gradient which satisfies equation (123) in the rest of the air is too large to keep the layer adjacent to the radiator in equilibrium; that layer rises and, similarly, the cold layer adjacent to the wall falls. A circulating pattern of thermal convection is…
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exertion by fluids
hazards of diving
- In human respiratory system: Swimming and diving
…any depth, is the vertical hydrostatic pressure gradient across the body. The effects of pressure, seen in many processes at the molecular and cellular levels, include the physiological effects of the increased partial pressures of the respiratory gases, the increased density of the respiratory gases, the effect of changes of…
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melting point of ice
- In ice: Thermal properties
…the melting point due to hydrostatic pressure: 0.0074 °C per bar. Thus for a glacier 300 metres (984 feet) thick, everywhere at the melting temperature, the ice at the base is 0.25 °C (0.45 °F) colder than at the surface.
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metamorphic rocks
- In metamorphic rock: Pressure
Fluids trapped in the pores of rocks during metamorphism exert pressure on the surrounding grains. At depths greater than a few kilometres within Earth, the magnitude of the fluid pressure is equal to the lithostatic pressure, reflecting the fact that mineral grain boundaries recrystallize in…
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ocean currents
- In ocean current: Pressure gradients
The hydrostatic pressure, p, at any depth below the sea surface is given by the equation p = gρz, where g is the acceleration of gravity, ρ is the density of seawater, which increases with depth, and z is the depth below the sea surface. This…
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pressure
- In pressure
Hydrostatic pressure is the stress, or pressure, exerted equally in all directions at points within a confined fluid (liquid or gas). It is the only stress possible in a fluid at rest. See Pascal’s principle.
Read More - In biosphere: Hydrostatic pressure
Because air and water have vastly different densities, the pressures experienced in terrestrial and aquatic habitats differ markedly. A column of water, so much denser than air, exerts a greater amount of pressure than a column of air. With each 10-metre (32.8-foot) increase…
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rocks
- In phase: Applications to petrology
…thus favoured (enlarged) with increasing pressure.
Read More - In rock: Rock mechanics
…of pressure may be simulated: confining (hydrostatic), due to burial under rock overburden, and internal (pore), due to pressure exerted by pore fluids contained in void space in the rock. Directed applied stress, such as compression, tension, and shear, is studied, as are the effects of increased temperature introduced with…
Read More - In rock: Effect of environmental conditions
(1) Confining pressure increases the elasticity, strength (e.g., yield point and ultimate fracture stress), and ductility. (2) Internal pore-fluid pressure reduces the effective stress acting on the sample, thus reducing the strength and ductility. The effective, or net, confining pressure is the external hydrostatic pressure minus…
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