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An Experimental Enquiry Concerning The Source Of The Heat Which Is Excited By Friction
''An Experimental Enquiry Concerning the Source of the Heat which is Excited by Friction'' is a scientific paper by Benjamin Thompson, Count Rumford, which was published in the Philosophical Transactions of the Royal Society in 1798. The paper provided a substantial challenge to established theories of heat, and began the 19th century revolution in thermodynamics. Background Rumford was an opponent of the caloric theory of heat which held that heat is a fluid that could be neither created nor destroyed. He had further developed the view that all gases and liquids are absolute non- conductors of heat. His views were out of step with the accepted science of the time and the latter theory had particularly been attacked by John Dalton and John Leslie. Rumford was heavily influenced by the argument from design and it is likely that he wished to grant water a privileged and providential status in the regulation of human life. Though Rumford was to come to associate heat with moti ...
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Benjamin Thompson
Sir Benjamin Thompson, Count Rumford, FRS (german: Reichsgraf von Rumford; March 26, 1753August 21, 1814) was an American-born British physicist and inventor whose challenges to established physical theory were part of the 19th-century revolution in thermodynamics. He served as lieutenant-colonel of the King's American Dragoons, part of the British Loyalist forces, during the American Revolutionary War. After the end of the war he moved to London, where his administrative talents were recognized when he was appointed a full colonel, and in 1784 he received a knighthood from King George III. A prolific designer, Thompson also drew designs for warships. He later moved to Bavaria and entered government service there, being appointed Bavarian Army Minister and re-organizing the army, and, in 1792, was made a Count of the Holy Roman Empire. Early years Thompson was born in rural Woburn, Massachusetts, on March 26, 1753; his birthplace is preserved as a museum. He was educated mainl ...
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John Locke
John Locke (; 29 August 1632 – 28 October 1704) was an English philosopher and physician, widely regarded as one of the most influential of Enlightenment thinkers and commonly known as the "father of liberalism". Considered one of the first of the British empiricists, following the tradition of Francis Bacon, Locke is equally important to social contract theory. His work greatly affected the development of epistemology and political philosophy. His writings influenced Voltaire and Jean-Jacques Rousseau, and many Scottish Enlightenment thinkers, as well as the American Revolutionaries. His contributions to classical republicanism and liberal theory are reflected in the United States Declaration of Independence. Internationally, Locke’s political-legal principles continue to have a profound influence on the theory and practice of limited representative government and the protection of basic rights and freedoms under the rule of law. Locke's theory of mind is of ...
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Mechanical Equivalent Of Heat
In the history of science, the mechanical equivalent of heat states that motion and heat are mutually interchangeable and that in every case, a given amount of work would generate the same amount of heat, provided the work done is totally converted to heat energy. The mechanical equivalent of heat was a concept that had an important part in the development and acceptance of the conservation of energy and the establishment of the science of thermodynamics in the 19th century. History and priority dispute Benjamin Thompson, Count Rumford, had observed the frictional heat generated by boring cannon at the arsenal in Munich, Germany circa 1797. Rumford immersed a cannon barrel in water and arranged for a specially blunted boring tool. He showed that the water could be boiled within roughly two and a half hours and that the supply of frictional heat was seemingly inexhaustible. Based on his experiments, he published " An Experimental Enquiry Concerning the Source of the Heat which ...
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Specific Heat
In thermodynamics, the specific heat capacity (symbol ) of a substance is the heat capacity of a sample of the substance divided by the mass of the sample, also sometimes referred to as massic heat capacity. Informally, it is the amount of heat that must be added to one unit of mass of the substance in order to cause an increase of one unit in temperature. The SI unit of specific heat capacity is joule per kelvin per kilogram, J⋅kg−1⋅K−1. For example, the heat required to raise the temperature of of water by is , so the specific heat capacity of water is . Specific heat capacity often varies with temperature, and is different for each state of matter. Liquid water has one of the highest specific heat capacities among common substances, about at 20 °C; but that of ice, just below 0 °C, is only . The specific heat capacities of iron, granite, and hydrogen gas are about 449 J⋅kg−1⋅K−1, 790 J⋅kg−1⋅K−1, and 14300 J⋅kg−1⋅K� ...
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Boiling
Boiling is the rapid vaporization of a liquid, which occurs when a liquid is heated to its boiling point, the temperature at which the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere. There are two main types of boiling: nucleate boiling where small bubbles of vapour form at discrete points, and critical heat flux boiling where the boiling surface is heated above a certain critical temperature and a film of vapor forms on the surface. Transition boiling is an intermediate, unstable form of boiling with elements of both types. The boiling point of water is 100 °C or 212 °F but is lower with the decreased atmospheric pressure found at higher altitudes. Boiling water is used as a method of making it potable by killing microbes and viruses that may be present. The sensitivity of different micro-organisms to heat varies, but if water is held at for one minute, most micro-organisms and viruses are inactivated. Ten ...
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Muzzle (firearms)
A gun barrel is a crucial part of gun-type weapons such as small firearms, artillery pieces, and air guns. It is the straight shooting tube, usually made of rigid high-strength metal, through which a contained rapid expansion of high-pressure gas(es) is used to propel a projectile out of the front end ( muzzle) at a high velocity. The hollow interior of the barrel is called the bore, and the diameter of the bore is called its caliber, usually measured in inches or millimetres. The first firearms were made at a time when metallurgy was not advanced enough to cast tubes capable of withstanding the explosive forces of early cannons, so the pipe (often built from staves of metal) needed to be braced periodically along its length for structural reinforcement, producing an appearance somewhat reminiscent of storage barrels being stacked together, hence the English name.''A History of Warfare'' - Keegan, John, Vintage 1993. History Gun barrels are usually metal. However, t ...
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Foundry
A foundry is a factory that produces metal castings. Metals are cast into shapes by melting them into a liquid, pouring the metal into a mold, and removing the mold material after the metal has solidified as it cools. The most common metals processed are aluminum and cast iron. However, other metals, such as bronze, brass, steel, magnesium, and zinc, are also used to produce castings in foundries. In this process, parts of desired shapes and sizes can be formed. Foundries are one of the largest contributors to the manufacturing recycling movement, melting and recasting millions of tons of scrap metal every year to create new durable goods. Moreover, many foundries use sand in their molding process. These foundries often use, recondition, and reuse sand, which is another form of recycling. Process In metalworking, casting involves pouring liquid metal into a mold, which contains a hollow cavity of the desired shape, and then allowing it to cool and solidify. The solidified ...
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Casting (metalworking)
In metalworking and jewelry making, casting is a process in which a liquid metal is delivered into a mold (usually by a crucible) that contains a negative impression (i.e., a three-dimensional negative image) of the intended shape. The metal is poured into the mold through a hollow channel called a sprue. The metal and mold are then cooled, and the metal part (the ''casting'') is extracted. Casting is most often used for making complex shapes that would be difficult or uneconomical to make by other methods. Casting processes have been known for thousands of years, and have been widely used for sculpture (especially in bronze), jewelry in precious metals, and weapons and tools. Highly engineered castings are found in 90 percent of durable goods, including cars, trucks, aerospace, trains, mining and construction equipment, oil wells, appliances, pipes, hydrants, wind turbines, nuclear plants, medical devices, defense products, toys, and more. Traditional techniques include ...
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Munich
Munich ( ; german: München ; bar, Minga ) is the capital and most populous city of the German state of Bavaria. With a population of 1,558,395 inhabitants as of 31 July 2020, it is the third-largest city in Germany, after Berlin and Hamburg, and thus the largest which does not constitute its own state, as well as the 11th-largest city in the European Union. The city's metropolitan region is home to 6 million people. Straddling the banks of the River Isar (a tributary of the Danube) north of the Bavarian Alps, Munich is the seat of the Bavarian administrative region of Upper Bavaria, while being the most densely populated municipality in Germany (4,500 people per km2). Munich is the second-largest city in the Bavarian dialect area, after the Austrian capital of Vienna. The city was first mentioned in 1158. Catholic Munich strongly resisted the Reformation and was a political point of divergence during the resulting Thirty Years' War, but remained physically unt ...
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Arsenal
An arsenal is a place where arms and ammunition are made, maintained and repaired, stored, or issued, in any combination, whether privately or publicly owned. Arsenal and armoury (British English) or armory (American English) are mostly regarded as synonyms, although subtle differences in usage exist. A sub-armory is a place of temporary storage or carrying of weapons and ammunition, such as any temporary post or patrol vehicle that is only operational in certain times of the day. Etymology The term in English entered the language in the 16th century as a loanword from french: arsenal, itself deriving from the it, arsenale, which in turn is thought to be a corruption of ar, دار الصناعة, , meaning "manufacturing shop". Types A lower-class arsenal, which can furnish the materiel and equipment of a small army, may contain a laboratory, gun and carriage factories, small-arms ammunition, small-arms, harness, saddlery tent and powder factories; in addition, it m ...
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Cannon
A cannon is a large- caliber gun classified as a type of artillery, which usually launches a projectile using explosive chemical propellant. Gunpowder ("black powder") was the primary propellant before the invention of smokeless powder during the late 19th century. Cannons vary in gauge, effective range, mobility, rate of fire, angle of fire and firepower; different forms of cannon combine and balance these attributes in varying degrees, depending on their intended use on the battlefield. A cannon is a type of heavy artillery weapon. The word ''cannon'' is derived from several languages, in which the original definition can usually be translated as ''tube'', ''cane'', or ''reed''. In the modern era, the term ''cannon'' has fallen into decline, replaced by ''guns'' or ''artillery'', if not a more specific term such as howitzer or mortar, except for high-caliber automatic weapons firing bigger rounds than machine guns, called autocannons. The earliest known depict ...
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