Bernoulli's principle states that in fluid flow, an increase in velocity occurs simultaneously with decrease in pressure. It is named for the Dutch/Swiss mathematician/scientist Daniel Bernoulli, though it was previously understood by Leonhard Euler and others. For a mathematical formulation, see Bernoulli's equation. In a fluid flow with no viscosity, and therefore one in which a pressure difference is the only accelerating force, it is equivalent to Newton's laws of motion. A subset of the phases of matter, fluids include liquids, gases, plasmas and, to some extent, plastic solids. ... This article is about velocity in physics. ... Pressure (symbol: p) is the force per unit area acting on a surface in a direction perpendicular to that surface. ... Daniel Bernoulli Daniel Bernoulli (Groningen, February 9, 1700 – Basel, March 17, 1782) was a Dutch-born mathematician who spent much of his life in Basel, Switzerland. ... Leonhard Euler by Emanuel Handmann Leonhard Euler (IPA ) (April 15, 1707 – September 18, 1783) was a Swiss mathematician and physicist. ... In fluid dynamics, Bernoullis equation, derived by Daniel Bernoulli, describes the behavior of a fluid moving along a streamline. ... The pitch drop experiment at the University of Queensland. ... Newtons first and second laws, in Latin, from the original 1687 edition of the Principia Mathematica. ...

One way of understanding how an airfoil develops lift relies upon the pressure differential above and below a wing. The pressure can be calculated by finding the velocities around the wing and using Bernoulli's equation. However, this explanation often uses false information, such as the incorrect assumption that the two parcels of air which separate at the leading edge of a wing must meet again at the trailing edge. An airfoil (in American English, or aerofoil in British English) is the shape of a wing or blade (of a propeller or ships screw) as seen in cross-section. ... Lift consists of the sum of all the fluid dynamic forces on a body perpendicular to the direction of the external flow around that body. ... In fluid dynamics, Bernoullis equation, derived by Daniel Bernoulli, describes the behavior of a fluid moving along a streamline. ...

Bernoulli's principle is responsible for the venturi effect that is used in carburetors and elsewhere. In a carburetor, air is passed through a Venturi tube to increase its speed and therefore decrease its pressure. The low pressure air is routed over a tube leading to a fuel tank. The low pressure sucks the fuel into the airflow so that the combined fuel and air can be sent to the engine. The pressure reduction is proportional to the rate of air flow, so that more fuel is sucked in as the air flow increases, and the fuel/air mixture keeps the same proportion over a wide range of speeds. The pressure reduction effect can be observed by blowing over a straw; the liquid level will rise as the flow over the top of the straw increases in speed. The Venturi effect is a special case of the Bernoulli effect, in the case of fluid or air flow through a tube or pipe with a constriction in it. ... The carburetor (American spelling, carburettor or carburetter in Commonwealth countries, carb for short) is a device which mixes air and fuel for an internal-combustion engine. ... A fluid passing through smoothly varying constrictions experience changes in velocity and pressure, as described by Bernoullis principle. ...

Another important application is predicting and preventing cavitation. As an example, a ship's propeller rotating at high speed may cause the local water (or other liquid) pressure to decrease enough for the liquid to become a gas (boil at low temperature), producing bubbles. When these collapse, pitting occurs on the face of the propeller, and noise results. The latter may be detected by means of sonar. Cavitation is the phenomenon where small cavities of partial vacuum form in fluid, then rapidly collapse, producing a sharp sound. ... This article needs a complete rewrite for the reasons listed on the talk page. ... Boil or furuncle is a skin disease caused by the inflammation of hair follicles, thus resulting in the localized accumulation of pus and dead tissues. ... Soap bubbles Bubble may refer to: a pocket of air or gas caught within a solid or liquid (see cavitation) a spherical liquid film (often of surfactant, occasionally of bubble gum) filled with air or gas, such as a soap bubble in economics, a bubble is a situation where speculation... The F70 type frigates (here, La Motte-Picquet) are fitted with VDS (Variable Depth Sonar) type DUBV43 or DUBV43C tugged sonars Sonar (sound navigation and ranging) is a technique that uses sound propagation under water to navigate or to detect other watercraft. ...