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mechanics

(Encyclopedia)mechanics, branch of physics concerned with motion and the forces that tend to cause it; it includes study of the mechanical properties of matter, such as density, elasticity, and viscosity. Mechanics...

rock

(Encyclopedia)rock, aggregation of solid matter composed of one or more of the minerals forming the earth's crust. The scientific study of rocks is called petrology. Rocks are commonly divided, according to their o...

endocytosis

(Encyclopedia)endocytosis ĕnˌdōsītōˈsəs [key], in biology, process by which substances are taken into the cell. When the cell membrane comes into contact with a suitable food, a portion of the cell cytoplasm...

induction, in electricity and magnetism

(Encyclopedia)induction, in electricity and magnetism, common name for three distinct phenomena. Electromagnetic induction is the production of an electromotive force (emf) in a conductor as a result of a changing ...

cosmology

(Encyclopedia)cosmology, area of science that aims at a comprehensive theory of the structure and evolution of the entire physical universe. The earliest pre-Ptolemaic theories assumed that the earth was the cent...

heredity

(Encyclopedia)heredity, transmission from generation to generation through the process of reproduction in plants and animals of factors which cause the offspring to resemble their parents. That like begets like has...

holography

(Encyclopedia)holography hŏlŏgˈrəfē, hō– [key], method of reproducing a three-dimensional image of an object by means of light wave patterns recorded on a photographic plate or film. Holography is sometimes...

ozone layer

(Encyclopedia)ozone layer or ozonosphere, region of the stratosphere containing relatively high concentrations of ozone, located at altitudes of 12–30 mi (19–48 km) above the earth's surface. Ozone in the ozone...

magnetic resonance

(Encyclopedia)magnetic resonance, in physics and chemistry, phenomenon produced by simultaneously applying a steady magnetic field and electromagnetic radiation (usually radio waves) to a sample of atoms and then a...

teeth

(Encyclopedia)CE5 A. Upper and lower teeth of an adult B. Cross section of a molar teeth, hard, calcified structures embedded in the bone of the jaws of vertebrates that perform the primary function of masticat...