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Kater Pendulum
A Kater's pendulum is a reversible free swinging pendulum invented by British physicist and army captain Henry Kater in 1817 (made public on 29 January 1818), for use as a gravimeter instrument to measure the local acceleration of gravity. Its advantage is that, unlike previous pendulum gravimeters, the pendulum's centre of gravity and center of oscillation do not have to be determined, allowing a greater accuracy. For about a century, until the 1930s, Kater's pendulum and its various refinements remained the standard method for measuring the strength of the Earth's gravity during geodetic surveys. It is now used only for demonstrating pendulum principles. Description A pendulum can be used to measure the acceleration of gravity ''g'' because for narrow swings (when the small angle approximation is valid) its period of swing ''T'' depends only on ''g'' and its length ''L'': :T = 2 \pi \sqrt \qquad \qquad \qquad (1)\, So by measuring the length ''L'' and period ''T'' of a pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kater Pendulum Use
Kater, besides meaning ''tomcat'' or ''hangover'' in Dutch and German, is the surname of the following people: * Fritz Kater, German trade unionist *Henry Kater, German-British physicist * Michael Hans Kater, German-Canadian historian * Norman William Kater (1861–1930), Australian physician pastoralist politician * Peter Kater, American pianist See also * ''Kater'' or ''Tomcat'' (2016 film), 2016 Austrian film * Cater (other) * Kata people The Katir (also spelled Kati, Kator and Kata) are a Nuristani tribe in Afghanistan and Pakistan. Etymology The Katir a 'tɘor Kata Kafir group was ''numerically'' the most dominant group of the Siah-Posh (Persian "Black Wearer/Clothed") trib ..., also known as Katir or Kator * Katoor dynasty, also known as Kator or Katur {{Surname ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oblate Spheroid
A spheroid, also known as an ellipsoid of revolution or rotational ellipsoid, is a quadric surface obtained by rotating an ellipse about one of its principal axes; in other words, an ellipsoid with two equal semi-diameters. A spheroid has circular symmetry. If the ellipse is rotated about its major axis, the result is a ''prolate spheroid'', elongated like a rugby ball. The American football is similar but has a pointier end than a spheroid could. If the ellipse is rotated about its minor axis, the result is an ''oblate spheroid'', flattened like a lentil or a plain M&M. If the generating ellipse is a circle, the result is a sphere. Due to the combined effects of gravity and rotation, the figure of the Earth (and of all planets) is not quite a sphere, but instead is slightly flattened in the direction of its axis of rotation. For that reason, in cartography and geodesy the Earth is often approximated by an oblate spheroid, known as the reference ellipsoid, instead of a sphe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Expansion
Thermal expansion is the tendency of matter to increase in length, area, or volume, changing its size and density, in response to an increase in temperature (usually excluding phase transitions). Substances usually contract with decreasing temperature (thermal contraction), with rare exceptions within limited temperature ranges ('' negative thermal expansion''). Temperature is a monotonic function of the average molecular kinetic energy of a substance. As energy in particles increases, they start moving faster and faster, weakening the intermolecular forces between them and therefore expanding the substance. When a substance is heated, molecules begin to vibrate and move more, usually creating more distance between themselves. The relative expansion (also called strain) divided by the change in temperature is called the material's coefficient of linear thermal expansion and generally varies with temperature. Prediction If an equation of state is available, it can be used t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kater Pendulum
A Kater's pendulum is a reversible free swinging pendulum invented by British physicist and army captain Henry Kater in 1817 (made public on 29 January 1818), for use as a gravimeter instrument to measure the local acceleration of gravity. Its advantage is that, unlike previous pendulum gravimeters, the pendulum's centre of gravity and center of oscillation do not have to be determined, allowing a greater accuracy. For about a century, until the 1930s, Kater's pendulum and its various refinements remained the standard method for measuring the strength of the Earth's gravity during geodetic surveys. It is now used only for demonstrating pendulum principles. Description A pendulum can be used to measure the acceleration of gravity ''g'' because for narrow swings (when the small angle approximation is valid) its period of swing ''T'' depends only on ''g'' and its length ''L'': :T = 2 \pi \sqrt \qquad \qquad \qquad (1)\, So by measuring the length ''L'' and period ''T'' of a pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bohnenberger
Johann Gottlieb Friedrich von Bohnenberger (5 June 1765 – 19 April 1831) was a German astronomer born at Simmozheim, Württemberg. He studied at the University of Tübingen. In 1798, he was appointed professor of mathematics and astronomy at the University. He published: * ''Anleitung zur geographischen Ortsbestimmung'' (Guide to geographic locations), 1795 * ''Astronomie'' (Astronomy), 1811 * ''Anfangsgründe der höhern Analysis'' (Initial reasons of higher analysis), 1812. In 1817, he systematically explained the design and use of a gyroscope apparatus which he called simply a “Machine.” Several examples of the 'Machine' were constructed by Johann Wilhelm Gottlob Buzengeiger of Tübingen. Johann Friedrich Benzenberg had already mentioned Bohnenberger's invention (describing it at length) in several letters beginning in 1810. Bohnenberger died at Tübingen. The lunar crater Lunar craters are impact craters on Earth's Moon. The Moon's surface has m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaspard De Prony
Baron Gaspard Clair François Marie Riche de Prony (22 July 1755 – 29 July 1839) was a French mathematician and engineer, who worked on hydraulics. He was born at Chamelet, Beaujolais, France and died in Asnières-sur-Seine, France. Education and early works He was Engineer-in-Chief of the ational school of bridges and roads a technical school in Paris. The trigonometric and logarithmic tables of the cadastre In 1791, Prony embarked on the task of producing logarithmic and trigonometric tables for the French Cadastre (geographic survey). The effort was sanctioned by the French National Assembly, which, after the French Revolution wanted to bring uniformity to the multiple measurements and standards used throughout the nation. In particular, his tables were intended for precise land surveys, as part of a greater cadastre effort. The tables were vast, calculating logarithms from 1 to 200,000, with values calculated to between fourteen and twenty-nine decimal places, ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society
The Royal Society, formally The Royal Society of London for Improving Natural Knowledge, is a learned society and the United Kingdom's national academy of sciences. The society fulfils a number of roles: promoting science and its benefits, recognising excellence in science, supporting outstanding science, providing scientific advice for policy, education and public engagement and fostering international and global co-operation. Founded on 28 November 1660, it was granted a royal charter by Charles II of England, King Charles II and is the oldest continuously existing scientific academy in the world. The society is governed by its Council, which is chaired by the society's president, according to a set of statutes and standing orders. The members of Council and the president are elected from and by its Fellows, the basic members of the society, who are themselves elected by existing Fellows. , there are about 1,700 fellows, allowed to use the postnominal title FRS (Fellow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angular Momentum
Angular momentum (sometimes called moment of momentum or rotational momentum) is the rotational analog of Momentum, linear momentum. It is an important physical quantity because it is a Conservation law, conserved quantity – the total angular momentum of a closed system remains constant. Angular momentum has both a direction (geometry), direction and a magnitude, and both are conserved. Bicycle and motorcycle dynamics, Bicycles and motorcycles, flying discs, Rifling, rifled bullets, and gyroscopes owe their useful properties to conservation of angular momentum. Conservation of angular momentum is also why hurricanes form spirals and neutron stars have high rotational rates. In general, conservation limits the possible motion of a system, but it does not uniquely determine it. The three-dimensional angular momentum for a point particle is classically represented as a pseudovector , the cross product of the particle's position vector (relative to some origin) and its mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean-Charles De Borda
Jean-Charles, chevalier de Borda (4 May 1733 – 19 February 1799) was a French mathematician, physicist, and Navy officer. Biography Borda was born in the city of Dax to Jean‐Antoine de Borda and Jeanne‐Marie Thérèse de Lacroix. In 1756, Borda wrote ''Mémoire sur le mouvement des projectiles'', a product of his work as a military engineer. For that, he was elected to the French Academy of Sciences in 1764. Borda was a mariner and a scientist, spending time in the Caribbean testing out advances in chronometers. Between 1777 and 1778, he participated in the American Revolutionary War. In 1781, he was put in charge of several vessels in the French Navy. In 1782, he was captured by the English, and was returned to France shortly after. He returned as an engineer in the French Navy, making improvements to waterwheels and pumps. He was appointed as France's Inspector of Naval Shipbuilding in 1784, and with the assistance of the naval architect Jacques-Noël Sané in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Marie De La Condamine
Charles Marie de La Condamine (; 28 January 1701 – 4 February 1774) was a French explorer, geographer, and mathematician. He spent ten years in territory which is now Ecuador, measuring the length of a degree of latitude at the equator and preparing the first map of the Amazon region based on astro-geodetic observations. Furthermore he was a contributor to the ''Encyclopédie''. Biography Charles Marie de La Condamine was born in Paris as a son of well-to-do parents, Charles de La Condamine and Louise Marguerite Chourses. He studied at the Collège Louis-le-Grand in Paris, where he was trained in humanities as well as in mathematics. After finishing his studies, he enlisted in the army and fought in the war against Spain (1719). After returning from the war, he became acquainted with scientific circles in Paris. On 12 December 1730 he became a member of the Académie des Sciences and was appointed Assistant Chemist at the Academy. In 1729 La Condamine and his friend Volta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean Picard
Jean Picard (21 July 1620 – 12 July 1682) was a French astronomer and priest born in La Flèche, where he studied at the Jesuit Collège Royal Henry-Le-Grand. He is principally notable for his accurate measure of the size of the Earth, based on a careful survey of one degree of latitude along the Paris Meridian. Geodesy Picard was the first person to measure the size of the Earth to a reasonable degree of accuracy in an arc measurement survey conducted in 1669–1670, for which he is honored with a pyramid at Juvisy-sur-Orge. Guided by Maurolycus's methodology and Willebrord Snellius's mathematics for doing so, Picard achieved this by measuring one degree of latitude along the Paris Meridian using triangulation along thirteen triangles stretching from Paris to the clocktower of Sourdon, near Amiens. His measurements produced a result of for one degree of latitude, which gives a corresponding terrestrial radius of . Isaac Newton was to use this value in his th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Center Of Gravity
In physics, the center of mass of a distribution of mass in space (sometimes referred to as the barycenter or balance point) is the unique point at any given time where the weighted relative position of the distributed mass sums to zero. For a rigid body containing its center of mass, this is the point to which a force may be applied to cause a linear acceleration without an angular acceleration. Calculations in mechanics are often simplified when formulated with respect to the center of mass. It is a hypothetical point where the entire mass of an object may be assumed to be concentrated to visualise its motion. In other words, the center of mass is the particle equivalent of a given object for application of Newton's laws of motion. In the case of a single rigid body, the center of mass is fixed in relation to the body, and if the body has uniform density, it will be located at the centroid. The center of mass may be located outside the physical body, as is sometimes the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
