- Doppler , Christian Johann
- (1803–1853) Austrian physicistChristian Doppler, the son of a stonemason from the Austrian city of Salzburg, studied mathematics at the Vienna Polytechnic. In 1835 he started teaching at a school in Prague and six years later was appointed professor of mathematics at the Technical Academy there.Doppler's fame comes from his discovery in 1842 of the Doppler effect – the fact that the observed frequency of a wave depends on the velocity of the source relative to the observer. The effect can be observed with sound waves. If the source is moving toward the observer, the pitch is higher; if it moves away, the pitch is lower. A common example is the fall in frequency of a train's whistle or a vehicle siren as it passes. Doppler's principle was tested experimentally in 1843 by Christoph Buys Ballot, who used a train to pull trumpeters at different speeds past musicians who had perfect pitch.Doppler also tried to apply his principle to light waves, with limited success. It was Armand Fizeau in 1848 who suggested that at high relative velocities the apparent color of the source would be changed by the motion: an object moving toward the observer would appear bluer; one moving away would appear redder. The shift in the spectra of celestial objects (the Doppler shift) is used to measure the rate of recession or approach relative to the Earth.
Scientists. Academic. 2011.
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Doppler,Christian Johann — Doppler, Christian Johann. 1803 1853. Austrian physicist and mathematician who first enunciated the principle known as the Doppler effect in 1842. * * * … Universalium
Christian Johann Doppler — Christian Doppler Christian Andreas Doppler Christian Andreas Doppler (Salzbourg, 29 novembre 1803 Venise, 17 mars 1853) était un mathématicien et un physicien a … Wikipédia en Français
Christian Johann Doppler — noun Austrian physicist famous for his discovery of the Doppler effect (1803 1853) • Syn: ↑Doppler • Instance Hypernyms: ↑physicist … Useful english dictionary
Doppler — Johann Christian, Austrian mathematician and physicist, 1803–1853. See D. echocardiography, D. effect, D. phenomenon, D. shift, D. ultrasonography. A diagnostic instrument that emits an ultrasonic beam into the body; the ultrasound reflected from … Medical dictionary
Christian Andreas Doppler — Christian Doppler, Portraitzeichnung Christian Johann Doppler (* 29. November 1803 in Salzburg; † 17. März 1853 in Venedig) war ein bedeutender österreichischer Mathematiker und Physiker. Bekannt ist Doppler heute durch den von ihm theoretisch… … Deutsch Wikipedia
Christian Doppler — Born 29 November 1803(1803 11 29) Salzburg, Austria … Wikipedia
Doppler Nunatak — (74°51′S 71°41′W / 74.85°S 71.683°W / 74.85; 71.683) is a nunatak lying southwest of Mount Mende in the Sky Hi Nunataks. Named by Advisory Committee on Antar … Wikipedia
Johann Gregor Mendel — Gregor Mendel Johann Gregor Mendel (* 22. Juli 1822 in Heinzendorf bei Odrau, Österreichisch Schlesien; † 6. Januar 1884 in Brünn) war Augustiner und Naturforscher. Die meisten seiner Publikationen behandeln meteorologische Themen. Er war… … Deutsch Wikipedia
Doppler — I. adjective Date: 1905 of, relating to, being, or utilizing a shift in frequency in accordance with the Doppler effect; also of or relating to Doppler radar II. biographical name Christian Johann 1803 1853 Austrian physicist … New Collegiate Dictionary
Doppler — Dọpp|ler 〈m. 3〉 = Doppeler * * * Dọpp|ler, der; s, [zu ↑ doppeln (2)] (südd., österr.): 1. erneuerte Schuhsohle. 2. Zweiliterflasche. * * * Dọppler, Christian Johann, österreichischer Physiker und Mathematiker, * … Universal-Lexikon