The law, discovered by Daniel Bernoulli, which states that when air speeds up its pressure is reduced, and when the air slows down its pressure is increased.
Daniel Bernoulli explained that the faster the molecules within a fluid move, the less pressure they exert on objects around them. This applies to all fluids, including water, air and gases. For example, the water in a pond will exert more pressure on the pond's bottom, than a flowing stream with the same amount of water will exert on the streambed.
There is, in general, such a relation between pressure and velocity, that whenever the velocity of a fluid (such as air or water) is high, the pressure is low and vice versa.
It describes the relationship between the velocity and pressure exerted by a moving fluid. According to this principle, the pressure exerted by a fluid decreases as the velocity of the fluid increases.
In physics, the concept that as the speed of a moving fluid (liquid or gas) increases, the pressure within that fluid decreases. Originally formulated in 1738 by the Swiss mathematician and physicist Daniel Bernoulli, it states that the total energy in a steadily flowing fluid system is a constant along the flow path. An increase in the fluid's speed must therefore be matched by a decrease in its pressure. Bernoulli's principle applies in nozzles, where flow accelerates and pressure drops as the tube diameter is reduced. It is also the principle behind orifice or Venturi flow meters. These meters measure the pressure difference between a low-speed fluid in an approach pipe and the high-speed fluid at the smaller orifice diameter to determine flow velocities and thus to meter the flow rate. Bernoulli's principle is sometimes mistakenly used to explain the net force in a system that includes a moving fluid, such as lift on an airplane wing, thrust of a ship's propeller, or drifting of a spinning baseball. The principle, however, only applies to systems that do not produce a net force. ( 058)
Air flowing over an airfoil results in an increase in flow speed over the upper curved surface. Since a velocity increase in fluid flow results in a corresponding pressure decrease, the increased airflow over the upper surface of the airfoil produces a lift on the airfoil because of lower pressure exerted on the upper surface. Named for Daniel Bernoulli (1700 -1782), a Swiss physicist who discovered the effect.
Bernoulli's Principle states that an increase in the velocity of a fluid is always accompanied by a decrease in pressure.
States that air travelling at a higher speed generates less pressure than air travelling at a lower speed. A boomerang aerofoil forces the air at the top to move further within the same time, and therefore faster. This creates upwards lift.