| A | B |
|---|
| fluid | any material that can flow and that takes the shape of its container |
| pascal | (Pa) the SI unit of pressure; equal to the force of 1 N exerted over an area of one square meter |
| pressure | the amount of force exerted on a given area; expressed in pascals (Pa) |
| atmospheric pressure | the pressure caused by the weight of the atmosphere |
| density | the amount of matter in a given space; mass per unit volume |
| hydraulic device | a device that uses liquids to transmit pressure from one point to another |
| Pascal's principle | the principle that states that a change in pressure at any point in an enclosed fluid is transmitted equally to all parts of that fluid |
| Archimedes' principle | the principle that states that the buoyant force on an object in a fluid is an upward force equal to the weight of the volume of fluid that the object displaces |
| buoyant force | the upward force that fluids exert on all matter, buoyant force opposes gravitational force |
| Bernoulli's principle | the principle that states that as the speed of a moving fluid increases, its pressure decreases |
| lift | an upward force on an object (such as a wing) that opposes the downward pull of gravity; differences in pressure above and below the object contribute to lift |
| thrust | the forward force produced by an airplane's engines; thrust opposes drag |
| drag | the force that opposes or restricts motion in a fluid; drag opposes thrust |
| turbulence | an irregular or unpredictable flow of fluids that can cause drag; lift is often reduced by turbulence |
