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Cavendish Experiment
The Cavendish experiment, performed in 1797–1798 by English scientist Henry Cavendish, was the first experiment to measure the force of gravity between masses in the laboratory and the first to yield accurate values for the gravitational constant. Because of the unit conventions then in use, the gravitational constant does not appear explicitly in Cavendish's work. Instead, the result was originally expressed as the specific gravity of Earth, or equivalently the Earth mass, mass of Earth. His experiment gave the first accurate values for these geophysics, geophysical constants. The experiment was devised sometime before 1783 by geologist John Michell, who constructed a torsion balance apparatus for it. However, Michell died in 1793 without completing the work. After his death the apparatus passed to Francis Wollaston (philosopher), Francis John Hyde Wollaston and then to Cavendish, who rebuilt the apparatus but kept close to Michell's original plan. Cavendish then carried out a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavendish Experiment
The Cavendish experiment, performed in 1797–1798 by English scientist Henry Cavendish, was the first experiment to measure the force of gravity between masses in the laboratory and the first to yield accurate values for the gravitational constant. Because of the unit conventions then in use, the gravitational constant does not appear explicitly in Cavendish's work. Instead, the result was originally expressed as the specific gravity of Earth, or equivalently the Earth mass, mass of Earth. His experiment gave the first accurate values for these geophysics, geophysical constants. The experiment was devised sometime before 1783 by geologist John Michell, who constructed a torsion balance apparatus for it. However, Michell died in 1793 without completing the work. After his death the apparatus passed to Francis Wollaston (philosopher), Francis John Hyde Wollaston and then to Cavendish, who rebuilt the apparatus but kept close to Michell's original plan. Cavendish then carried out a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cavendish Experiment Schematic
Cavendish may refer to: People * The House of Cavendish, a British aristocratic family * Margaret Cavendish (1623–1673), British poet, philosopher, and scientist * Cavendish (author) (1831–1899), pen name of Henry Jones, English author on card games and tennis * Henry Cavendish (1731–1810), British natural philosopher and scientist * Mark Cavendish (born 1985), Manx professional road and track cyclist * Diana Cavendish from Little Witch Academia * Thomas Cavendish (1560-1592), English sailor who circumnavigated (1586-1588). Places Australia * County of Cavendish, Queensland * Cavendish Road, Brisbane, Queensland * Cavendish, Victoria Bermuda * Cavendish Tribe, original name of Devonshire Parish, Bermuda Canada * Cavendish, Alberta * Cavendish, Newfoundland and Labrador * Cavendish, a former township, subsequently merged and renamed to form Trent Lakes, Ontario * Cavendish, Prince Edward Island * Cavendish Beach, Prince Edward Island England * Cavendish, Suffolk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newton's Law Of Universal Gravitation
Newton's law of universal gravitation is usually stated as that every particle attracts every other particle in the universe with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between their centers.It was shown separately that separated spherically symmetrical masses attract and are attracted as if all their mass were concentrated at their centers. The publication of the law has become known as the " first great unification", as it marked the unification of the previously described phenomena of gravity on Earth with known astronomical behaviors. This is a general physical law derived from empirical observations by what Isaac Newton called inductive reasoning. It is a part of classical mechanics and was formulated in Newton's work '' Philosophiæ Naturalis Principia Mathematica'' ("the ''Principia''"), first published on 5 July 1687. When Newton presented Book 1 of the unpublished text in April 1686 to the Ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isaac Newton
Sir Isaac Newton (25 December 1642 – 20 March 1726/27) was an English mathematician, physicist, astronomer, alchemist, theologian, and author (described in his time as a "natural philosopher"), widely recognised as one of the greatest mathematicians and physicists and among the most influential scientists of all time. He was a key figure in the philosophical revolution known as the Enlightenment. His book (''Mathematical Principles of Natural Philosophy''), first published in 1687, established classical mechanics. Newton also made seminal contributions to optics, and shares credit with German mathematician Gottfried Wilhelm Leibniz for developing infinitesimal calculus. In the , Newton formulated the laws of motion and universal gravitation that formed the dominant scientific viewpoint for centuries until it was superseded by the theory of relativity. Newton used his mathematical description of gravity to derive Kepler's laws of planetary motion, account for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torsion Coefficient
A torsion spring is a spring that works by twisting its end along its axis; that is, a flexible elastic object that stores mechanical energy when it is twisted. When it is twisted, it exerts a torque in the opposite direction, proportional to the amount (angle) it is twisted. There are various types: *A torsion bar is a straight bar of metal or rubber that is subjected to twisting (shear stress) about its axis by torque applied at its ends. *A more delicate form used in sensitive instruments, called a torsion fiber consists of a fiber of silk, glass, or quartz under tension, that is twisted about its axis. *A helical torsion spring, is a metal rod or wire in the shape of a helix (coil) that is subjected to twisting about the axis of the coil by sideways forces (bending moments) applied to its ends, twisting the coil tighter. *Clocks use a spiral wound torsion spring (a form of helical torsion spring where the coils are around each other instead of piled up) sometimes cal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gaussian Gravitational Constant
The Gaussian gravitational constant (symbol ) is a parameter used in the orbital mechanics of the Solar System. It relates the orbital period to the orbit's semi-major axis and the mass of the orbiting body in Solar masses. The value of historically expresses the mean angular velocity of the system of Earth+Moon and the Sun considered as a two body problem, with a value of about 0.986 degrees per day, or about 0.0172 radians per day. As a consequence of law of gravitation and Kepler's third law, is directly proportional to the square root of the standard gravitational parameter of the Sun, and its value in radians per day follows by setting Earth's semi-major axis (the astronomical unit, au) to unity, :(rad/d) ()0.5·au−1.5. A value of rad/day was determined by Carl Friedrich Gauss in his 1809 work ''Theoria Motus Corporum Coelestium in Sectionibus Conicis Solem Ambientum'' ("Theory of the Motion of the Heavenly Bodies Moving about the Sun in Conic Sections"). Gaus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CODATA
The Committee on Data of the International Science Council (CODATA) was established in 1966 as the Committee on Data for Science and Technology, originally part of the International Council of Scientific Unions, now part of the International Science Council (ISC). CODATA exists to promote global collaboration to advance open science and to improve the availability and usability of data for all areas of research. CODATA supports the principle that data produced by research and susceptible to be used for research should be as open as possible and as closed as necessary. CODATA works also to advance the interoperability and the usability of such data: research data should be FAIR (findable, accessible, interoperable and reusable). By promoting the policy, technological and cultural changes that are essential to promote open science, CODATA helps advance ISC's vision and mission of advancing science as a global public good. The CODATA Strategic Plan 2015 and Prospectus of Strate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crust (geology)
In geology, the crust is the outermost solid shell of a rocky planet, dwarf planet, or natural satellite. It is usually distinguished from the underlying mantle by its chemical makeup; however, in the case of icy satellites, it may be distinguished based on its phase (solid crust vs. liquid mantle). The crusts of Earth, Mercury, Venus, Mars, Io, the Moon and other planetary bodies formed via igneous processes and were later modified by erosion, impact cratering, volcanism, and sedimentation. Most terrestrial planets have fairly uniform crusts. Earth, however, has two distinct types: continental crust and oceanic crust. These two types have different chemical compositions and physical properties and were formed by different geological processes. Types of crust Planetary geologists divide crust into three categories based on how and when it formed. Primary crust / primordial crust This is a planet's "original" crust. It forms from solidification of a magma ocean. Towa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron () is a chemical element with symbol Fe (from la, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen (32.1% and 30.1%, respectively), forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust. In its metallic state, iron is rare in the Earth's crust, limited mainly to deposition by meteorites. Iron ores, by contrast, are among the most abundant in the Earth's crust, although extracting usable metal from them requires kilns or furnaces capable of reaching or higher, about higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BCE and the use of iron tools and weapons began to displace copper alloys, in some regions, only around 1200 BCE. That event is considered the transition from the Bronze Age to the Iron A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schiehallion Experiment
The Schiehallion experiment was an 18th-century experiment to determine the mean density of the Earth. Funded by a grant from the Royal Society, it was conducted in the summer of 1774 around the Scottish mountain of Schiehallion, Perthshire. The experiment involved measuring the tiny deflection of the vertical due to the gravitational attraction of a nearby mountain. Schiehallion was considered the ideal location after a search for candidate mountains, thanks to its isolation and almost symmetrical shape. The experiment had previously been considered, but rejected, by Isaac Newton as a practical demonstration of his theory of gravitation; however, a team of scientists, notably Nevil Maskelyne, the Astronomer Royal, was convinced that the effect would be detectable and undertook to conduct the experiment. The deflection angle depended on the relative densities and volumes of the Earth and the mountain: if the density and volume of Schiehallion could be ascertained, then so could ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Hutton
Charles Hutton FRS FRSE LLD (14 August 1737 – 27 January 1823) was a British mathematician and surveyor. He was professor of mathematics at the Royal Military Academy, Woolwich from 1773 to 1807. He is remembered for his calculation of the density of the earth from Nevil Maskelyne's measurements collected during the Schiehallion experiment. Life Hutton was born on Percy Street in Newcastle upon Tyne in the north of England, the son of a superintendent of mines, who died when he was still very young. He was educated at a school at Jesmond, kept by Mr Ivison, an Anglican clergyman. There is reason to believe, on the evidence of two pay-bills, that for a short time in 1755 and 1756 Hutton worked in the colliery at Old Long Benton. Following Ivison's promotion to a living, Hutton took over the Jesmond school, which, in consequence of his increasing number of pupils, he relocated to nearby Stotes Hall. While he taught during the day at Stotes Hall, which overlooked Jesmond De ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Outer Core
Earth's outer core is a fluid layer about thick, composed of mostly iron and nickel that lies above Earth's solid inner core and below its mantle. The outer core begins approximately beneath Earth's surface at the core-mantle boundary and ends beneath Earth's surface at the inner core boundary. Properties Unlike Earth's solid, inner core, its outer core is liquid. Evidence for a fluid outer core includes seismology which shows that seismic shear-waves are not transmitted through the outer core. Although having a composition similar to Earth's solid inner core, the outer core remains liquid as there is not enough pressure to keep it in a solid state. Seismic inversions of body waves and normal modes constrain the radius of the outer core to be 3483 km with an uncertainty of 5 km, while that of the inner core is 1220±10 km. Estimates for the temperature of the outer core are about in its outer region and near the inner core. Modeling has shown that the outer core, be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
