Ch. 14 Key Terms - University Physics Volume 1 | OpenStax

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Key Terms

absolute pressure: sum of gauge pressure and atmospheric pressure

Archimedes’ principle: buoyant force on an object equals the weight of the fluid it displaces

Bernoulli’s equation: equation resulting from applying conservation of energy to an incompressible frictionless fluid: $p + \frac{1}{2} ρ v^{2} + ρ g h = constant,$ throughout the fluid

Bernoulli’s principle: Bernoulli’s equation applied at constant depth:
$p_{1} + \frac{1}{2} ρ v_{1}^{2} = p_{2} + \frac{1}{2} ρ v_{2}^{2}$

buoyant force: net upward force on any object in any fluid due to the pressure difference at different depths

density: mass per unit volume of a substance or object

flow rate: abbreviated Q, it is the volume V that flows past a particular point during a time t, or $Q = d V / d t$

fluids: liquids and gases; a fluid is a state of matter that yields to shearing forces

gauge pressure: pressure relative to atmospheric pressure

hydraulic jack: simple machine that uses cylinders of different diameters to distribute force

hydrostatic equilibrium: state at which water is not flowing, or is static

ideal fluid: fluid with negligible viscosity

laminar flow: type of fluid flow in which layers do not mix

Pascal’s principle: change in pressure applied to an enclosed fluid is transmitted undiminished to all portions of the fluid and to the walls of its container

Poiseuille’s law: rate of laminar flow of an incompressible fluid in a tube: $Q = \frac{(p_{2} - p_{1}) π r^{4}}{8 η l} .$

Poiseuille’s law for resistance: resistance to laminar flow of an incompressible fluid in a tube: $R = \frac{8 η l}{π r^{4}}$

pressure: force per unit area exerted perpendicular to the area over which the force acts

Reynolds number: dimensionless parameter that can reveal whether a particular flow is laminar or turbulent

specific gravity: ratio of the density of an object to a fluid (usually water)

turbulence: fluid flow in which layers mix together via eddies and swirls

turbulent flow: type of fluid flow in which layers mix together via eddies and swirls

viscosity: measure of the internal friction in a fluid

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Authors: William Moebs, Samuel J. Ling, Jeff Sanny
Publisher/website: OpenStax
Book title: University Physics Volume 1
Publication date: Sep 19, 2016
Location: Houston, Texas
Book URL: https://openstax.org/books/university-physics-volume-1/pages/1-introduction
Section URL: https://openstax.org/books/university-physics-volume-1/pages/14-key-terms

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