Definition of A Fluid
Fluids are substances that do not permanently change under an enormous amount of stress. A solid tends to deform in order to remain at equilibrium under a great deal of stress. Fluids are defined as both liquids and gases because the molecules inside the fluid are much weaker than those molecules contained in a solid. When referring to the density of a fluid in terms of a liquid, there is a small percentage of change to the liquid’s density as pressure is increased. If the fluid is referred to as a gas, the density will change greatly depending on the amount of pressure applied due to the equation of state for gases (p=ρRT). In the study of the flow of liquids, the term used while referring to the little change in density is called incompressible flow. In the study of the flow of gases, the rapid increase due to an increase of pressure is called compressible flow.
Read more about this topic: Gas Dynamics
Famous quotes containing the words definition of a, definition of, definition and/or fluid:
“It’s a rare parent who can see his or her child clearly and objectively. At a school board meeting I attended . . . the only definition of a gifted child on which everyone in the audience could agree was “mine.””
—Jane Adams (20th century)
“The very definition of the real becomes: that of which it is possible to give an equivalent reproduction.... The real is not only what can be reproduced, but that which is always already reproduced. The hyperreal.”
—Jean Baudrillard (b. 1929)
“Although there is no universal agreement as to a definition of life, its biological manifestations are generally considered to be organization, metabolism, growth, irritability, adaptation, and reproduction.”
—The Columbia Encyclopedia, Fifth Edition, the first sentence of the article on “life” (based on wording in the First Edition, 1935)
“Eye, gazelle, delicate wanderer,
Drinker of horizon’s fluid line;
Ear that suspends on a chord
The spirit drinking timelessness;
Touch, love, all senses;”
—Stephen Spender (1909–1995)