Search results
Results from the WOW.Com Content Network
Capillary action of water (polar) compared to mercury (non-polar), in each case with respect to a polar surface such as glass (≡Si–OH). Capillary action (sometimes called capillarity, capillary motion, capillary rise, capillary effect, or wicking) is the process of a liquid flowing in a narrow space without the assistance of external forces like gravity.
However, for a 2 cm (0.79 in) radius tube, the water would rise 0.7 mm (0.028 in), and for a 0.2 mm (0.0079 in) radius tube, the water would rise 70 mm (2.8 in). Capillary action is used by many plants to bring up water from the soil.
This capillary action is the "upward movement of water through the vadose zone" (Coduto, 266). [8] Increased water infiltration, such as that caused by heavy rainfall, brings about a reduction in matric suction, following the relationship described by the soil water characteristic curve (SWCC), resulting in a reduction of the soil's shear ...
In Beskow’s studies, he defined this soil moisture tension as “capillary pressure” (and soil water as “capillary water”). Beskow determined that the soil type and effective stress on the soil particles influenced frost heave, where effective stress is the sum of pressure from above ground and the capillary pressure. [18]
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 capillary length will vary for different liquids and different conditions. Here is a picture of a water droplet on a lotus leaf. If the temperature is 20 o then = 2.71mm . The capillary length or capillary constant is a length scaling factor that relates gravity and surface tension.
The equation is derived for capillary flow in a cylindrical tube in the absence of a gravitational field, but is sufficiently accurate in many cases when the capillary force is still significantly greater than the gravitational force. In his paper from 1921 Washburn applies Poiseuille's Law for fluid motion in a circular tube.
In physics, the Young–Laplace equation (/ l ə ˈ p l ɑː s /) is an algebraic equation that describes the capillary pressure difference sustained across the interface between two static fluids, such as water and air, due to the phenomenon of surface tension or wall tension, although use of the latter is only applicable if assuming that the wall is very thin.