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Franz Melde
Franz Emil Melde (March 11, 1832 in Großenlüder near Fulda – March 17, 1901 in Marburg) was a German physicist and professor. A graduate of the University of Marburg under Christian Ludwig Gerling, he later taught there, focusing primarily on acoustics, also making contributions to fields including fluid mechanics and meteorology. He began in 1860 as Gerling's assistant at the University's Mathematical and Physical Institute, succeeding him in 1864. Standing waves were first discovered by Melde, who coined the term "standing wave" (''stehende Welle'') around 1860. What is known as " Melde's experiment", "a lecture-room standby", demonstrates standing waves and their patterns on a string, is used to measure the speed of transverse wave, and to determine the effect of tension, length, and mass on the transverse waves of a string. In 1859 Melde generated parametric oscillations in a string by employing a tuning fork to periodically vary the tension at twice the resonan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standing Wave
In physics, a standing wave, also known as a stationary wave, is a wave that oscillates in time but whose peak amplitude profile does not move in space. The peak amplitude of the wave oscillations at any point in space is constant with respect to time, and the oscillations at different points throughout the wave are in phase. The locations at which the absolute value of the amplitude is minimum are called nodes, and the locations where the absolute value of the amplitude is maximum are called antinodes. Standing waves were first noticed by Michael Faraday in 1831. Faraday observed standing waves on the surface of a liquid in a vibrating container. Franz Melde coined the term "standing wave" (German: ''stehende Welle'' or ''Stehwelle'') around 1860 and demonstrated the phenomenon in his classic experiment with vibrating strings. This phenomenon can occur because the medium is moving in the direction opposite to the movement of the wave, or it can arise in a stationary medium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
String Vibration
A vibration in a strings (music), string is a wave. Acoustic resonance#Resonance of a string, Resonance causes a vibrating string to produce a sound with constant frequency, i.e. constant pitch (music), pitch. If the length or tension of the string is correctly adjusted, the sound produced is a musical tone. Vibrating strings are the basis of string instruments such as guitars, cellos, and pianos. Wave The velocity of propagation of a wave in a string (v) is proportional to the square root of the force of tension of the string (T) and inversely proportional to the square root of the linear density (\mu) of the string: v = \sqrt. This relationship was discovered by Vincenzo Galilei in the late 1500s. Derivation Source: Let \Delta x be the length of a piece of string, m its mass, and \mu its linear density. If angles \alpha and \beta are small, then the horizontal components of Tension (mechanics), tension on either side can both be approximated by a constant T, for which th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
19th-century German Physicists
The 19th (nineteenth) century began on 1 January 1801 ( MDCCCI), and ended on 31 December 1900 ( MCM). The 19th century was the ninth century of the 2nd millennium. The 19th century was characterized by vast social upheaval. Slavery was abolished in much of Europe and the Americas. The First Industrial Revolution, though it began in the late 18th century, expanding beyond its British homeland for the first time during this century, particularly remaking the economies and societies of the Low Countries, the Rhineland, Northern Italy, and the Northeastern United States. A few decades later, the Second Industrial Revolution led to ever more massive urbanization and much higher levels of productivity, profit, and prosperity, a pattern that continued into the 20th century. The Islamic gunpowder empires fell into decline and European imperialism brought much of South Asia, Southeast Asia, and almost all of Africa under colonial rule. It was also marked by the collapse of the large S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1901 Deaths
Nineteen or 19 may refer to: * 19 (number), the natural number following 18 and preceding 20 * one of the years 19 BC, AD 19, 1919, 2019 Films * ''19'' (film), a 2001 Japanese film * ''Nineteen'' (film), a 1987 science fiction film Music * 19 (band), a Japanese pop music duo Albums * ''19'' (Adele album), 2008 * ''19'', a 2003 album by Alsou * ''19'', a 2006 album by Evan Yo * ''19'', a 2018 album by MHD * ''19'', one half of the double album ''63/19'' by Kool A.D. * ''Number Nineteen'', a 1971 album by American jazz pianist Mal Waldron * ''XIX'' (EP), a 2019 EP by 1the9 Songs * "19" (song), a 1985 song by British musician Paul Hardcastle. * "Nineteen", a song by Bad4Good from the 1992 album ''Refugee'' * "Nineteen", a song by Karma to Burn from the 2001 album ''Almost Heathen''. * "Nineteen" (song), a 2007 song by American singer Billy Ray Cyrus. * "Nineteen", a song by Tegan and Sara from the 2007 album '' The Con''. * "XIX" (song), a 2014 song by Slipkno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1832 Births
Year 183 ( CLXXXIII) was a common year starting on Tuesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Aurelius and Victorinus (or, less frequently, year 936 ''Ab urbe condita''). The denomination 183 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years. Events By place Roman Empire * An assassination attempt on Emperor Commodus by members of the Senate fails. Births * January 26 – Lady Zhen, wife of the Cao Wei state Emperor Cao Pi (d. 221) * Hu Zong, Chinese general, official and poet of the Eastern Wu state (d. 242) * Liu Zan (Zhengming), Chinese general of the Eastern Wu state (d. 255) * Lu Xun Zhou Shuren (25 September 1881 – 19 October 1936), better known by his pen name Lu Xun (or Lu Sun; ; Wade–Giles: Lu Hsün), was a Chinese writer, essayist, poet, and literary criti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernst 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 pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
World's Columbian Exposition
The World's Columbian Exposition (also known as the Chicago World's Fair) was a world's fair held in Chicago (''City in a Garden''); I Will , image_map = , map_caption = Interactive Map of Chicago , coordinates = , coordinates_footnotes = , subdivision_type = Country , subdivision_name ... in 1893 to celebrate the 400th anniversary of Christopher Columbus's arrival in the New World in 1492. The centerpiece of the Fair, held in Jackson Park (Chicago), Jackson Park, was a large water pool representing the voyage Columbus took to the New World. Chicago had won the right to host the fair over several other cities, including New York City, Washington, D.C., and St. Louis. The exposition was an influential social and cultural event and had a profound effect on American Architecture of the United States, architecture, the arts, American industrial optimism, and Chicago's image. The layout of the Chicago Columbian E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Academy Of Sciences Leopoldina
The German National Academy of Sciences Leopoldina (german: Deutsche Akademie der Naturforscher Leopoldina – Nationale Akademie der Wissenschaften), short Leopoldina, is the national academy of Germany, and is located in Halle (Saale). Founded on January 1, 1652, based on academic models in Italy, it was originally named the ''Academia Naturae Curiosorum'' until 1687 when Emperor Leopold I raised it to an academy and named it after himself. It was since known under the German name ''Deutsche Akademie der Naturforscher Leopoldina'' until 2007, when it was declared to be Germany's National Academy of Sciences. History ' The Leopoldina was founded in the imperial city of Schweinfurt on 1 January 1652 under the Latin name sometimes translated into English as "Academy of the Curious as to Nature." It was founded by four local physicians- Johann Laurentius Bausch, the first president of the society, Johann Michael Fehr, Georg Balthasar Metzger, and Georg Balthasar Wohlfarth; and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landsmannschaft (Studentenverbindung)
A Landsmannschaft (; Latin ''natio'', plural nationes) is a German fraternity of several fraternity forms called ''Studentenverbindung''. The older forms of ''Landsmannschaften'' were part of corporations and are closely aligned with the beginnings of universities in medieval times of the 12th and 13th centuries. The newer forms of ''Landsmannschaften'' are a kind of reform corps and most ''Landsmannschaften'' are members of the Coburger Convent. This is also the term for a Jewish burial society: landsmanshaft History In order to understand the history of German fraternities, it needs to be known that the first universities in Europe were established in the 12th and 13th century in Paris (France), Bologna and Padua (Italy), and later also in Oxford and Cambridge (England). Students joined groups in regards to region in order to have protection as well as support in being heard in their interests. The two early forms were called nations (Nationes) or colleges (Collegien) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frequency
Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is equal to one event per second. The period is the interval of time between events, so the period is the reciprocal of the frequency. For example, if a heart beats at a frequency of 120 times a minute (2 hertz), the period, —the interval at which the beats repeat—is half a second (60 seconds divided by 120 beats). Frequency is an important parameter used in science and engineering to specify the rate of oscillatory and vibratory phenomena, such as mechanical vibrations, audio signals (sound), radio waves, and light. Definitions and units For cyclical phenomena such as oscillations, waves, or for examples of simple harmonic motion, the term ''frequency'' is defined as the number of cycles or vibrations per unit of time. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Resonance
Resonance describes the phenomenon of increased amplitude that occurs when the frequency of an applied periodic force (or a Fourier component of it) is equal or close to a natural frequency of the system on which it acts. When an oscillating force is applied at a resonant frequency of a dynamic system, the system will oscillate at a higher amplitude than when the same force is applied at other, non-resonant frequencies. Frequencies at which the response amplitude is a relative maximum are also known as resonant frequencies or resonance frequencies of the system. Small periodic forces that are near a resonant frequency of the system have the ability to produce large amplitude oscillations in the system due to the storage of vibrational energy. Resonance phenomena occur with all types of vibrations or waves: there is mechanical resonance, orbital resonance, acoustic resonance, electromagnetic resonance, nuclear magnetic resonance (NMR), electron spin resonance (ESR) and reso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tuning Fork
A tuning fork is an acoustic resonator in the form of a two-pronged fork with the prongs (tines) formed from a U-shaped bar of elastic metal (usually steel). It resonates at a specific constant pitch when set vibrating by striking it against a surface or with an object, and emits a pure musical tone once the high overtones fade out. A tuning fork's pitch depends on the length and mass of the two prongs. They are traditional sources of standard pitch for tuning musical instruments. The tuning fork was invented in 1711 by British musician John Shore, sergeant trumpeter and lutenist to the royal court. Description A tuning fork is a fork-shaped acoustic resonator used in many applications to produce a fixed tone. The main reason for using the fork shape is that, unlike many other types of resonators, it produces a very pure tone, with most of the vibrational energy at the fundamental frequency. The reason for this is that the frequency of the first overtone is about = = t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
