Liquid

From WikiMD.com - Food, Medicine & Wellness Encyclopedia


A liquid is one of the four fundamental states of matter, along with solid, gas, and plasma. A liquid is a nearly incompressible fluid that conforms to the shape of its container but retains a (nearly) constant volume independent of pressure. As such, it is one of the most common states of matter on Earth and is essential for life.

Properties[edit | edit source]

Liquids have a definite volume but no fixed shape. They are characterized by their ability to flow and take the shape of their container. The molecules in a liquid are closely packed but not in a fixed position, allowing them to move freely past one another.

Particle model of liquid

Viscosity[edit | edit source]

Viscosity is a measure of a liquid's resistance to flow. It describes the internal friction of a moving fluid. A liquid with high viscosity, such as honey, flows more slowly than a liquid with low viscosity, such as water.

Viscosities

Surface Tension[edit | edit source]

Surface tension is the elastic tendency of a fluid surface which makes it acquire the least surface area possible. This property allows insects, such as the water strider, to walk on water.

Water drop

Cohesion and Adhesion[edit | edit source]

Cohesion refers to the attraction between molecules of the same substance, while adhesion refers to the attraction between molecules of different substances. These properties are crucial in phenomena such as capillary action.

Density and Buoyancy[edit | edit source]

The density of a liquid is its mass per unit volume. Buoyancy is the ability of a liquid to exert an upward force on an object placed in it, which is why objects float or sink.

Behavior[edit | edit source]

Flow and Fluid Dynamics[edit | edit source]

Liquids flow and can be described by the principles of fluid dynamics. The study of liquids in motion is called hydrodynamics.

Thermal Properties[edit | edit source]

Liquids have specific heat capacities and thermal conductivities that affect how they transfer heat. The immiscibility of hot and cold water can be visualized using thermal imaging.

Hot and cold water immiscibility

Phase Transitions[edit | edit source]

Liquids can transition to other states of matter. When heated, they can become gases through evaporation or boiling. When cooled, they can become solids through freezing.

Applications[edit | edit source]

Liquids are used in a wide range of applications, from industrial processes to everyday life. They are essential in hydraulics, lubrication, and as solvents in chemical reactions.

Cavitation[edit | edit source]

Cavitation is a phenomenon where rapid changes in pressure in a liquid lead to the formation of small vapor-filled cavities. These cavities can collapse violently, causing damage to surfaces such as propellers.

Cavitating propeller

Lava Lamps[edit | edit source]

Lava lamps are a popular decorative item that demonstrate the principles of liquid immiscibility and density differences.

Blue lava lamp

Related Pages[edit | edit source]

WikiMD
Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD

Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD

WikiMD's Wellness Encyclopedia

Let Food Be Thy Medicine
Medicine Thy Food - Hippocrates

Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates, categories Wikipedia, licensed under CC BY SA or similar.

Contributors: Prab R. Tumpati, MD