negative pressure difference measurement
71Europe, history of — Introduction history of European peoples and cultures from prehistoric times to the present. Europe is a more ambiguous term than most geographic expressions. Its etymology is doubtful, as is the physical extent of the area it designates.… …
72human development — ▪ biology Introduction the process of growth and change that takes place between birth and maturity. Human growth is far from being a simple and uniform process of becoming taller or larger. As a child (child development) gets bigger,… …
73atom — /at euhm/, n. 1. Physics. a. the smallest component of an element having the chemical properties of the element, consisting of a nucleus containing combinations of neutrons and protons and one or more electrons bound to the nucleus by electrical… …
74electromagnetic radiation — Physics. radiation consisting of electromagnetic waves, including radio waves, infrared, visible light, ultraviolet, x rays, and gamma rays. [1950 55] * * * Energy propagated through free space or through a material medium in the form of… …
75Heat capacity — Thermodynamics …
76Mass–energy equivalence — E=MC2 redirects here. For other uses, see E=MC2 (disambiguation). 4 meter tall sculpture of Einstein s 1905 E = mc2 formula at the 2006 Walk of Ideas, Berlin, Germany In physics, mass–energy equivalence is the concept that the …
77chemical bonding — ▪ chemistry Introduction any of the interactions that account for the association of atoms into molecules, ions, crystals, and other stable species that make up the familiar substances of the everyday world. When atoms approach one another …
78solids, mechanics of — ▪ physics Introduction science concerned with the stressing (stress), deformation (deformation and flow), and failure of solid materials and structures. What, then, is a solid? Any material, fluid or solid, can support normal forces.… …
79Properties of water — H2O and HOH redirect here. For other uses, see H2O (disambiguation) and HOH (disambiguation). This article is about the physical and chemical properties of pure water. For general discussion and its distribution and importance in life, see Water …
80Tide — This article is about tides in the Earth s oceans. For other uses, see Tide (disambiguation). Tidal redirects here. For other uses, see Tidal (disambiguation). High Tide redirects here. For other uses, see High Tide (disambiguation) …
