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transformer

(Encyclopedia)transformer, electrical device used to transfer an alternating current or voltage from one electric circuit to another by means of electromagnetic induction. The simplest type of transformer consists ...

X ray

(Encyclopedia)CE5 Typical X-ray composite spectrum (intensity as a function of frequency) X ray, invisible, highly penetrating electromagnetic radiation of much shorter wavelength (higher frequency) than visibl...

diathermy

(Encyclopedia)diathermy dīˈəthûrˌmē [key], therapeutic measure used in medicine to generate heat in the body tissues. Electrodes and other instruments are used to transmit electric current to surface structur...

motor, electric

(Encyclopedia)CE5 Motor: In the AC motor, current fed to the conducting loop of wire causes it to rotate in the magnetic field, thus turning the shaft on which the loop is mounted. In the DC motor, the direction...

Shawnee Prophet

(Encyclopedia)Shawnee Prophet, 1775?–1837?, Native North American of the Shawnee tribe; brother of Tecumseh. His Native American name was Tenskwautawa. He announced himself as a prophet bearing a revelation from ...

Ronsard, Pierre de

(Encyclopedia)Ronsard, Pierre de pyĕr də rôNsärˈ [key], 1524–1585, French poet. As page, then squire, Ronsard seemed destined for a career at court both in France and abroad. However, deafness turned him to ...

Barton, Derek H. R.

(Encyclopedia)Barton, Derek H. R., 1918–98, British chemist, b. Gravesend, England, grad. Imperial College of Science and Technology (B.S. 1940, Ph.D. 1942, D.Sc. 1949). He was on the faculty of Imperial College ...

Marler, Peter Robert

(Encyclopedia)Marler, Peter Robert, 1928–2014, British ethologist, b. Slough, England, Ph.D University College London, 1952, and Cambridge, 1954. At Cambridge he was introduced to the sonic spectrograph, an instr...

corona, in astronomy

(Encyclopedia)corona, luminous envelope surrounding the sun, outside the chromosphere. Its density is less than one billionth that of the earth's atmosphere. The corona is visible only at the time of totality durin...

Mössbauer, Rudolf Ludwig

(Encyclopedia)Mössbauer, Rudolf Ludwig, 1929–2011, German physicist, Ph.D. Max Planck Institute for Medical Research, Heidelberg, Germany, 1957. Mössbauer was a professor at the California Institute of Technolo...