Sports Medicine & Kinesiology

Marathoners, take your marks... and fluid and salt!

Legend states that after the Greek army defeated the invading Persian forces near the city of Marathon in 490 B.C.E., the courier Pheidippides ran to Athens to report the victory and then immediately dropped dead. The story—and ...

Medical research

Engineering lymphatic vessels as a therapeutic to heal the heart

The cardiovascular system is a complex network of veins, arteries and capillaries. Within that network, lymphatic vessels are critical to the heart's ability to heal in the event of a heart attack. When they're functional, ...

Fluid

In physics, a fluid is a substance that continually deforms (flows) under an applied shear stress, no matter how small. Fluids are a subset of the phases of matter and include liquids, gases, plasmas and, to some extent, plastic solids.

In common usage, "fluid" is often used as a synonym for "liquid", with no implication that gas could also be present. For example, "brake fluid" is hydraulic oil and will not perform its required function if there is gas in it. This colloquial usage of the term is also common in medicine and in nutrition ("take plenty of fluids").

Liquids form a free surface (that is, a surface not created by the container) while gases do not. The distinction between solids and fluid is not entirely obvious. The distinction is made by evaluating the viscosity of the substance. Silly Putty can be considered to behave like a solid or a fluid, depending on the time period over which it is observed. It is best described as a viscoelastic fluid. There are many examples of substances proving difficult to classify. A particularly interesting one is pitch, as demonstrated in the pitch drop experiment currently running at the University of Queensland.

This text uses material from Wikipedia, licensed under CC BY-SA