What is Bernoulli's principle?

Bernoulli's principle is a fundamental concept in fluid dynamics stating that an increase in a fluid's speed occurs simultaneously with a decrease in pressure or a decrease in potential and internal energy. Named after Swiss mathematician Daniel Bernoulli and first published in 1738, the principle can be derived from Isaac Newton's second law of motion or the conservation of energy. It explains practical phenomena such as the Venturi effect, where fluids speed up through constrictions while pressure drops.

What we know

• Bernoulli's principle relates the pressure, speed, and height of a moving fluid, stating that for a horizontally flowing fluid, an increase in speed occurs alongside a decrease in pressure. [2]
• Daniel Bernoulli published the principle in his 1738 book Hydrodynamica, though Leonhard Euler derived Bernoulli's equation in its usual form in 1752. [2]
• The principle can be derived directly from Isaac Newton's second law of motion or from the principle of conservation of energy. [2]
• The Venturi effect is an example of Bernoulli's principle, showing fluid pressure reduction when a moving fluid is funneled into a smaller pipe section. [4]

Where to go next

• whoWho was Daniel Bernoulli?
• a case in pointHow does the Venturi effect work?
• the bigger pictureWhat is fluid dynamics?
• how it workedHow does conservation of energy apply to fluids?
• whoWhat did Leonhard Euler contribute to physics?
• an unexpected connectionHow do fluid dynamics help model weapon detonations?The same broad discipline of fluid dynamics that explains everyday water flow and Bernoulli's principle is also used to model fission weapon detonations.

Sources

• [1]Bernoulli's principle (Wikidata Q181328) · CC0 1.0
• [2]Bernoulli's principle · CC BY-SA 4.0
• [3]Fluid dynamics · CC BY-SA 4.0
• [4]Venturi effect · CC BY-SA 4.0
• [5]Archimedes' principle · CC BY-SA 4.0