Capillary action in the context of Transpiration stream

A dip pen is a writing instrument used to apply ink to paper. It usually consists of a metal nib with a central slit that acts as a capillary channel like those of fountain pen nibs, mounted in a handle or holder, often made of wood. Other materials can be used for the holder, including bone, metal and plastic; some pens are made entirely of glass.

Generally dip pens have no ink reservoir, so the user must refill the ink from an ink bowl or bottle to continue drawing or writing. Sometimes a simple tubular reservoir can be clipped to the top of the pen, allowing for several minutes of uninterrupted use. Refilling can be done by dipping into an inkwell, but it is also possible to charge the pen with an eyedropper, a syringe, or a brush, which gives more control over the amount of ink applied. Thus, "dip pens" are not necessarily dipped; many illustrators call them nib pens.

A fountain pen is a writing instrument that uses a metal nib to apply water-based ink to paper. It is distinguished from earlier dip pens by using an internal reservoir to hold ink, eliminating the need to repeatedly dip the pen in an inkwell during use. The pen draws ink from the reservoir through a feed to the nib and deposits the ink on paper via a combination of gravity and capillary action. Filling the reservoir with ink may be achieved manually, via the use of an eyedropper or syringe, or via an internal filling mechanism that creates suction (for example, through a piston mechanism) or a vacuum to transfer ink directly through the nib into the reservoir. Some pens employ removable reservoirs in the form of pre-filled ink cartridges.

Brazing is a metal-joining process in which two or more metal items are joined by melting and flowing a filler metal into the joint, with the filler metal having a lower melting point than the adjoining metal.

During the brazing process, the filler metal flows into the gap between close-fitting parts by capillary action. The filler metal is brought slightly above its melting (liquidus) temperature while protected by a suitable atmosphere, usually a flux. It then flows over the base metal (in a process known as wetting) and is then cooled to join the work pieces together.

The vadose zone (from the Latin word for "shallow"), also termed the unsaturated zone, is the part of Earth between the land surface and the top of the phreatic zone, the position at which the groundwater (the water in the soil's pores) is at atmospheric pressure. Hence, the vadose zone extends from the top of the ground surface to the water table.

Water in the vadose zone has a pressure head less than atmospheric pressure, and is retained by a combination of adhesion (funiculary groundwater), and capillary action (capillary groundwater). If the vadose zone envelops soil, the water contained therein is termed soil moisture. In fine grained soils, capillary action can cause the pores of the soil to be fully saturated above the water table at a pressure less than atmospheric. The vadose zone does not include the area that is still saturated above the water table, often referred to as the capillary fringe.

The water table is the upper surface of the phreatic zone or zone of saturation. The zone of saturation is where the pores and fractures of the ground are saturated with groundwater, which may be fresh, saline, or brackish, depending on the locality. It can also be simply explained as the depth below which the ground is saturated. The portion above the water table is the vadose zone. It may be visualized as the "surface" of the subsurface materials that are saturated with groundwater in a given vicinity.

In coarse soils, the water table settles at the surface where the water pressure head is equal to the atmospheric pressure (where gauge pressure = 0). In soils where capillary action is strong, the water table is pulled upward, forming a capillary fringe.

Unconventional (oil and gas) reservoirs, or unconventional resources (resource plays) are accumulations where oil and gas phases are tightly bound to the rock fabric by strong capillary forces, requiring specialized measures for evaluation and extraction.

Aerogels are a class of synthetic porous ultralight material derived from a gel, in which the liquid component for the gel has been replaced with a gas, without significant collapse of the gel structure. The result is a solid with extremely low density and extremely low thermal conductivity. Aerogels can be made from a variety of chemical compounds. Silica aerogels feel like fragile styrofoam to the touch, while some polymer-based aerogels feel like rigid foams.

Aerogels are produced by extracting the liquid component of a gel through supercritical drying or freeze-drying. This allows the liquid to be slowly dried off without causing the solid matrix in the gel to collapse from capillary action, as would happen with conventional evaporation. The first aerogels were produced from silica gels. Kistler's later work involved aerogels based on alumina, chromia, and tin dioxide. Carbon aerogels were first developed in the late 1980s.

Moisture management or moisture-wicking is a functional property in textiles that enables them to transfer moisture from the skin, by capillary action through the fabric, spreading it over a large external surface area, which helps in drying quickly. The property is one of the most important for thermal comfort of textiles.

The teapot effect, also known as dribbling, is a fluid dynamics phenomenon that occurs when a liquid being poured from a container runs down the spout or the body of the vessel instead of flowing out in an arc.

Markus Reiner coined the term "teapot effect" in 1956 to describe the tendency of liquid to dribble down the side of a vessel while pouring. Reiner received his PhD at TU Wien in 1913 and made significant contributions to the development of the study of flow behavior known as rheology. Reiner believed the teapot effect could be explained by Bernoulli's principle, which states that an increase in the speed of a fluid is always accompanied by a decrease in its pressure. When tea is poured from a teapot, the liquid's speed increases as it flows through the narrowing spout. This decrease in pressure was what Reiner thought to cause the liquid to dribble down the side of the pot.However, a 2021 study found the primary cause of the phenomenon to be an interaction of inertia and capillary forces. The study found that the smaller the angle between the container wall and the liquid surface, the more the teapot effect is slowed down.

A sponge (/ˈspʌndʒ/ SPUNJ) is a cleaning aid made of soft, porous material. Typically used for cleaning impervious surfaces, sponges are especially good at absorbing water and water-based solutions.

Originally made from natural sea sponges, they are most commonly made from synthetic materials today.

A candle wick or lamp wick is usually made of braided cotton that holds the flame of a candle or oil lamp. A candle wick works by capillary action, conveying ("wicking") the fuel to the flame. When the liquid fuel, typically melted candle wax, reaches the flame it then vaporizes and combusts. In other words, the wick brings the liquified wax up into the flame to burn. The candle wick influences how the candle burns. Important characteristics of the wick include diameter, stiffness, fire-resistance, and tethering.

Water potential is the potential energy of water per unit volume relative to pure water in reference conditions. Water potential quantifies the tendency of water to move from one area to another due to osmosis, gravity, mechanical pressure and matrix effects such as capillary action (which is caused by surface tension). The concept of water potential has proved useful in understanding and computing water movement within plants, animals, and soil. Water potential is typically expressed in potential energy per unit volume and very often is represented by the Greek letter ψ.

Water potential integrates a variety of different potential drivers of water movement, which may operate in the same or different directions. Within complex biological systems, many potential factors may be operating simultaneously. For example, the addition of solutes lowers the potential (negative vector), while an increase in pressure increases the potential (positive vector). If the flow is not restricted, water will move from an area of higher water potential to an area that is lower potential. A common example is water with dissolved salts, such as seawater or the fluid in a living cell. These solutions have negative water potential, relative to the pure water reference. With no restriction on flow, water will move from the locus of greater potential (pure water) to the locus of lesser (the solution); flow proceeds until the difference in potential is equalized or balanced by another water potential factor, such as pressure or elevation.

Pore water pressure (sometimes abbreviated to pwp) refers to the pressure of groundwater held within a soil or rock, in gaps between particles (pores). Pore water pressures below the phreatic level of the groundwater are measured with piezometers. The vertical pore water pressure distribution in aquifers can generally be assumed to be close to hydrostatic.

In the unsaturated ("vadose") zone, the pore pressure is determined by capillarity and is also referred to as tension, suction, or matric pressure. Pore water pressures under unsaturated conditions are measured with tensiometers, which operate by allowing the pore water to come into equilibrium with a reference pressure indicator through a permeable ceramic cup placed in contact with the soil.

A helictite is a speleothem (cave-formed mineral) found in a limestone cave that changes its axis from the vertical at one or more stages during its growth. Helictites have a curving or angular form that looks as if they were grown in zero gravity. They are most likely the result of capillary forces acting on tiny water droplets, a force often strong enough at this scale to defy gravity.

Helictites are, perhaps, the most delicate of cave formations. They are usually made of needle-form calcite and aragonite. Helictite forms have been described in several types: ribbon helictites, saws, rods, butterflies, "hands", curly-fries, and "clumps of worms". They typically have radial symmetry. They can be easily crushed or broken by the slightest touch. Because of this, helictites are rarely seen within arm's reach in tourist caves.

The capillary fringe is the subsurface layer in which groundwater seeps up from a water table by capillary action to fill pores. Pores at the base of the capillary fringe are filled with water due to tension saturation. This saturated portion of the capillary fringe is less than the total capillary rise because of the presence of a mix in pore size. If the pore size is small and relatively uniform, it is possible that soils can be completely saturated with water for several feet above the water table. Alternately, when the pore size is large, the saturated portion will extend only a few inches above the water table. Capillary action supports a vadose zone above the saturated base, within which water content decreases with distance above the water table. In soils with a wide range in pore size, the unsaturated zone can be several times thicker than the saturated zone.

Some workers restrict their definition of the capillary fringe only to the tension-saturated base portion and exclude it wholly from the vadose zone. This is more common among workers addressing solute transport and water flow. Others define the capillary fringe as including both the tension-saturated and unsaturated portions. This is the preferred definition among workers dealing with the remediation of salt affected soils as well as those dealing with the vapor phase of soil processes and bioremediation. It is not uncommon to see the capillary fringe treated as a boundary condition separating the water table from the unsaturated zone, without defining it as a significant part of either.

A Molotov cocktail (among several other names – see § Etymology) is a hand-thrown incendiary weapon consisting of a frangible container filled with flammable substances and equipped with a fuse (typically a glass bottle filled with flammable liquids sealed with a cloth wick). In use, the fuse attached to the container is lit and the weapon is thrown, shattering on impact. This ignites the flammable substances contained in the bottle and spreads flames as the fuel burns.

Due to their relative ease of production, Molotov cocktails are typically improvised weapons. Their improvised usage spans criminals, gangsters, rioters, football hooligans, urban guerrillas, terrorists, irregular soldiers, freedom fighters, and even regular soldiers; usage in the latter case is often due to a shortage of equivalent military-issued munitions. Despite the weapon's improvised nature and uncertain quality, many modern militaries exercise the use of Molotov cocktails.