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Brownian movement

(Encyclopedia)Brownian movement or motion, zigzag, irregular motion exhibited by minute particles of matter when suspended in a fluid. The effect has been observed in all types of colloidal suspensions (see colloid...

solar energy

(Encyclopedia)solar energy, any form of energy radiated by the sun, including light, radio waves, and X rays, although the term usually refers to the visible light of the sun. Solar energy is needed by green plants...

Adler, Larry

(Encyclopedia)Adler, Larry (Lawrence Cecil Adler) ădˈlər [key], 1914–2001, American harmonica player, b. Baltimore. Adler, whose career spanned seven decades, is generally credited with elevating the harmonica...

retrograde motion

(Encyclopedia)retrograde motion, in astronomy, real or apparent movement of a planet, dwarf planet, moon, asteroid, or comet from east to west relative to the fixed stars. The most common direction of motion in the...

motion pictures

(Encyclopedia)motion pictures, movie-making as an art and an industry, including its production techniques, its creative artists, and the distribution and exhibition of its products (see also motion picture photogr...

motion sickness

(Encyclopedia)motion sickness, waves of nausea and vomiting experienced by some people, resulting from the sudden changes in movement of a vehicle. The ailment is also known as seasickness, car sickness, train sick...

states of matter

(Encyclopedia)states of matter, forms of matter differing in several properties because of differences in the motions and forces of the molecules (or atoms, ions, or elementary particles) of which they are composed...

electric shock

(Encyclopedia)electric shock, effect of the passage of a current of electricity through the body. Fatality may result from shocks of from 1 to 2 amperes and 500 to 1,000 volts. However, the effect of electric shock...

physics

(Encyclopedia)physics, branch of science traditionally defined as the study of matter, energy, and the relation between them; it was called natural philosophy until the late 19th cent. and is still known by this na...

polonium

(Encyclopedia)polonium pəlōˈnēəm [key], radioactive chemical element; symbol Po; at. no. 84; mass no. of most stable isotope 209; m.p. 254℃; b.p. 962℃; sp. gr. about 9.4; valence +2 or +4. Polonium is an e...
 

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