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Chladni
Ernst Florens Friedrich Chladni (, , ; 30 November 1756 – 3 April 1827) was a German physicist and musician. His most important work, for which he is sometimes labeled as the father of acoustics, included research on vibrating plates and the calculation of the speed of sound for different gases. He also undertook pioneering work in the study of meteorites and is regarded by some as the father of meteoritics. Early life Although Chladni was born in Wittenberg in Saxony, his family originated from Kremnica, then part of the Kingdom of Hungary and today a mining town in central Slovakia. Chladni has therefore been identified as German, Hungarian and Slovak. Chladni came from an educated family of academics and learned men. Chladni's great-grandfather, the Lutheran clergyman Georg Chladni (1637–1692), had left Kremnica in 1673 during the Counter Reformation. Chladni's grandfather, Martin Chladni (1669–1725), was also a Lutheran theologian and, in 1710, became p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chladni's Law
Chladni's law, named after Ernst Chladni, relates the frequency of modes of vibration for flat circular surfaces with fixed center as a function of the numbers ''m'' of diametric (linear) nodes and ''n'' of radial (circular) nodes. It is stated as the equation : f = C (m + 2n)^p where ''C'' and ''p'' are coefficients which depend on the properties of the plate. For flat circular plates, ''p'' is roughly 2, but Chladni's law can also be used to describe the vibrations of cymbals, handbells, and church bells A church bell in Christian architecture is a bell which is rung in a church for a variety of religious purposes, and can be heard outside the building. Traditionally they are used to call worshippers to the church for a communal service, and ... in which case ''p'' can vary from 1.4 to 2.4.. In fact, ''p'' can even vary for a single object, depending on which family of modes is being examined. References External linksA Study of Vibrating Platesby Derek Kverno and J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernst Heinrich Weber
Ernst Heinrich Weber (24 June 1795 – 26 January 1878) was a German physician who is considered one of the founders of experimental psychology. He was an influential and important figure in the areas of physiology and psychology during his lifetime and beyond. His studies on sensation and touch, along with his emphasis on good experimental techniques led to new directions and areas of study for future psychologists, physiologists, and anatomists. Ernst Weber was born into an academic background, with his father serving as a professor at the University of Wittenberg. Weber became a doctor, specializing in anatomy and physiology. Two of his younger brothers, Wilhelm and Eduard, were also influential in academia, both as scientists with one specializing in physics and the other in anatomy. Ernst became a lecturer and a professor at the University of Leipzig and stayed there until his retirement. Early life Ernst Heinrich Weber was born on 24 June 1795 in Wittenberg, Saxony, Holy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteorite
A meteorite is a solid piece of debris from an object, such as a comet, asteroid, or meteoroid, that originates in outer space and survives its passage through the atmosphere to reach the surface of a planet or Natural satellite, moon. When the original object enters the atmosphere, various factors such as friction, pressure, and chemical interactions with the atmospheric gases cause it to heat up and radiate energy. It then becomes a meteor and forms a Meteoroid#Fireball, fireball, also known as a shooting star; astronomers call the brightest examples "Bolide#Astronomy, bolides". Once it settles on the larger body's surface, the meteor becomes a meteorite. Meteorites vary greatly in size. For geologists, a bolide is a meteorite large enough to create an impact crater. Meteorites that are recovered after being observed as they transit the atmosphere and Impact event, impact the Earth are called meteorite falls. All others are known as meteorite finds. Meteorites have traditiona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Georg Christoph Lichtenberg
Georg Christoph Lichtenberg (1 July 1742 – 24 February 1799) was a German physicist, satirist, and Anglophile. As a scientist, he was the first to hold a professorship explicitly dedicated to experimental physics in Germany. He is remembered for his posthumously published notebooks, which he himself called '' sudelbücher'', a description modelled on the English bookkeeping term "waste books" or "scrapbooks", and for his discovery of tree-like electrical discharge patterns now called Lichtenberg figures. Life Georg Christoph Lichtenberg was born in Ober-Ramstadt near Darmstadt, Landgraviate of Hesse-Darmstadt, the youngest of 17 children. His father, Johann Conrad Lichtenberg, was a pastor ascending through the ranks of the church hierarchy, who eventually became superintendent for Darmstadt. Unusually for a clergyman in those times, he seems to have possessed a fair amount of scientific knowledge. Lichtenberg was educated at his parents' house until 10 years old, when he joined ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wittenberg
Wittenberg ( , ; Low Saxon language, Low Saxon: ''Wittenbarg''; meaning ''White Mountain''; officially Lutherstadt Wittenberg (''Luther City Wittenberg'')), is the fourth largest town in Saxony-Anhalt, Germany. Wittenberg is situated on the River Elbe, north of Leipzig and south-west of Berlin, and has a population of 46,008 (2018). Wittenberg is famous for its close connection with Martin Luther and the Protestant Reformation, for which it received the honourific ''Lutherstadt''. Several of Wittenberg's buildings are associated with the events, including a preserved part of the Augustinians, Augustinian monastery in which Luther lived, first as a monk and later as owner with his wife Katharina von Bora and family, considered to be the world's premier museum dedicated to Luther. Wittenberg was also the seat of the Elector of Saxony, a dignity held by the dukes of Duchy of Saxe-Wittenberg, Saxe-Wittenberg, making it one of the most powerful cities in the Holy Roman Empire. To ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kingdom Of Hungary
The Kingdom of Hungary was a monarchy in Central Europe that existed for nearly a millennium, from the Middle Ages into the 20th century. The Principality of Hungary emerged as a Christian kingdom upon the coronation of the first king Stephen I at Esztergom around the year 1000;Kristó Gyula – Barta János – Gergely Jenő: Magyarország története előidőktől 2000-ig (History of Hungary from the prehistory to 2000), Pannonica Kiadó, Budapest, 2002, , p. 687, pp. 37, pp. 113 ("Magyarország a 12. század második felére jelentős európai tényezővé, középhatalommá vált."/"By the 12th century Hungary became an important European factor, became a middle power.", "A Nyugat részévé vált Magyarország.../Hungary became part of the West"), pp. 616–644 his family (the Árpád dynasty) led the monarchy for 300 years. By the 12th century, the kingdom became a European middle power within the Western world. Due to the Ottoman occupation of the central and south ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slovakia
Slovakia (; sk, Slovensko ), officially the Slovak Republic ( sk, Slovenská republika, links=no ), is a landlocked country in Central Europe. It is bordered by Poland to the north, Ukraine to the east, Hungary to the south, Austria to the southwest, and the Czech Republic to the northwest. Slovakia's mostly mountainous territory spans about , with a population of over 5.4 million. The capital and largest city is Bratislava, while the second largest city is Košice. The Slavs arrived in the territory of present-day Slovakia in the fifth and sixth centuries. In the seventh century, they played a significant role in the creation of Samo's Empire. In the ninth century, they established the Principality of Nitra, which was later conquered by the Principality of Moravia to establish Great Moravia. In the 10th century, after the dissolution of Great Moravia, the territory was integrated into the Principality of Hungary, which then became the Kingdom of Hungary in 1000. In 1241 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
German People
, native_name_lang = de , region1 = , pop1 = 72,650,269 , region2 = , pop2 = 534,000 , region3 = , pop3 = 157,000 3,322,405 , region4 = , pop4 = 21,000 3,000,000 , region5 = , pop5 = 125,000 982,226 , region6 = , pop6 = 900,000 , region7 = , pop7 = 142,000 840,000 , region8 = , pop8 = 9,000 500,000 , region9 = , pop9 = 357,000 , region10 = , pop10 = 310,000 , region11 = , pop11 = 36,000 250,000 , region12 = , pop12 = 25,000 200,000 , region13 = , pop13 = 233,000 , region14 = , pop14 = 211,000 , region15 = , pop15 = 203,000 , region16 = , pop16 = 201,000 , region17 = , pop17 = 101,000 148,00 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encyclopædia Britannica
The (Latin for "British Encyclopædia") is a general knowledge English-language encyclopaedia. It is published by Encyclopædia Britannica, Inc.; the company has existed since the 18th century, although it has changed ownership various times through the centuries. The encyclopaedia is maintained by about 100 full-time editors and more than 4,000 contributors. The 2010 version of the 15th edition, which spans 32 volumes and 32,640 pages, was the last printed edition. Since 2016, it has been published exclusively as an online encyclopaedia. Printed for 244 years, the ''Britannica'' was the longest running in-print encyclopaedia in the English language. It was first published between 1768 and 1771 in the Scottish capital of Edinburgh, as three volumes. The encyclopaedia grew in size: the second edition was 10 volumes, and by its fourth edition (1801–1810) it had expanded to 20 volumes. Its rising stature as a scholarly work helped recruit eminent con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meteoritics
Meteoritics is the science that deals with meteors, meteorites, and meteoroids. It is closely connected to cosmochemistry, mineralogy and geochemistry. A specialist who studies meteoritics is known as a ''meteoriticist''. Scientific research in meteoritics includes the collection, identification, and classification of meteorites and the analysis of samples taken from them in a laboratory. Typical analyses include investigation of the minerals that make up the meteorite, their relative locations, orientations, and chemical compositions; analysis of isotope ratios; and radiometric dating. These techniques are used to determine the age, formation process, and subsequent history of the material forming the meteorite. This provides information on the history of the Solar System, how it formed and evolved, and the process of planet formation. History of investigation Before the documentation of L'Aigle it was generally believed that meteorites were a type of superstition and those w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hungarian People
Hungarians, also known as Magyars ( ; hu, magyarok ), are a nation and ethnic group native to Hungary () and Kingdom of Hungary, historical Hungarian lands who share a common Hungarian culture, culture, Hungarian history, history, Magyar tribes, ancestry, and Hungarian language, language. The Hungarian language belongs to the Uralic languages, Uralic language family. There are an estimated 15 million ethnic Hungarians and their descendants worldwide, of whom 9.6 million live in today's Hungary. About 2–3 million Hungarians live in areas that were part of the Kingdom of Hungary before the Treaty of Trianon in 1920 and are now parts of Hungary's seven neighbouring countries, Hungarians in Slovakia, Slovakia, Hungarians in Ukraine, Ukraine, Hungarians in Romania, Romania, Hungarians in Serbia, Serbia, Hungarians of Croatia, Croatia, Prekmurje, Slovenia, and Hungarians in Austria, Austria. Hungarian diaspora, Significant groups of people with Hungarian ancestry live in various oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Scientist
__NOTOC__ ''American Scientist'' (informally abbreviated ''AmSci'') is an American bimonthly science and technology magazine published since 1913 by Sigma Xi, The Scientific Research Society. In the beginning of 2000s the headquarters was in New Haven, CT. Each issue includes feature articles written by prominent scientists and engineers who review research in fields from molecular biology to computer engineering. Each issue also includes the work of cartoonists, including those of Sidney Harris, Benita Epstein Benita L. Epstein is a prolific gag cartoonist for magazines, greeting cards, websites and newspapers. She was a regular contributor to the comic strip ''Six Chix'', distributed by King Features Syndicate. Before becoming a cartoonist, Epstein ea ..., and Mark Heath. Also included is the ''Scientists' Nightstand'' that reviews a vast range of science-related books and novels. ''American Scientist Online'' () was launched in May 2003. References External links * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
