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Oppenheimer, J. Robert

(Encyclopedia)Oppenheimer, J. Robert ŏpˈənhīˌmər [key], 1904–67, American physicist, b. New York City, grad. Harvard (B.A., 1925), Ph.D. Univ. of Göttingen, 1927. He taught at the Univ. of California and t...

mass, in physics

(Encyclopedia)mass, in physics, the quantity of matter in a body regardless of its volume or of any forces acting on it. The term should not be confused with weight, which is the measure of the force of gravity (se...

sonar

(Encyclopedia)sonar sōˈnär [key], device used underwater for locating submerged objects and for submarine communication by means of sound waves. The term sonar is an acronym for sound navigation ranging. The mai...

Ovshinsky, Stanford Robert

(Encyclopedia)Ovshinsky, Stanford Robert, 1922–2012, American inventor and scientist, b. Akron, Ohio. Self-taught, he developed a new type of lathe in the 1940s, the first of many innovations and patents. Special...

Zeeman effect

(Encyclopedia)Zeeman effect, splitting of a single spectral line (see spectrum) into a group of closely spaced lines when the substance producing the single line is subjected to a uniform magnetic field. The effect...

Bernoulli's principle

(Encyclopedia)CE5 Bernoulli's principle Bernoulli's principle, physical principle formulated by Daniel Bernoulli that states that as the speed of a moving fluid (liquid or gas) increases, the pressure within th...

Chu, Steven

(Encyclopedia)Chu, Steven, 1948–, U.S. physicist and government official, b. St. Louis, Mo., grad. Univ. of Rochester (B.S., A.B. 1970), Univ. of California, Berkeley (Ph.D. 1976). He worked from 1978 at Bell Lab...

catabolism

(Encyclopedia)catabolism kətăbˈəlĭzˌəm [key], subdivision of metabolism involving all degradative chemical reactions in the living cell. Large polymeric molecules such as polysaccharides, nucleic acids, and ...

Bhabha, Homi Jehangir

(Encyclopedia)Bhabha, Homi Jehangir jəhänˌgērˈ bäˈbä [key], 1909–66, Indian physicist, b. Bombay (now Mumbai). He was educated at the Royal Institute of Science, Bombay, and at Cambridge, England, where h...

cosmic rays

(Encyclopedia)cosmic rays, charged particles moving at nearly the speed of light reaching the earth from outer space. Primary cosmic rays consist mostly of protons (nuclei of hydrogen atoms), some alpha particles (...