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Simple Machines
A simple machine is a mechanical device that changes the direction or magnitude of a force. In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force. Usually the term refers to the six classical simple machines that were defined by Renaissance scientists: * Lever * Wheel and axle * Pulley * Inclined plane * Wedge * Screw A simple machine uses a single applied force to do work against a single load force. Ignoring friction losses, the work done on the load is equal to the work done by the applied force. The machine can increase the amount of the output force, at the cost of a proportional decrease in the distance moved by the load. The ratio of the output to the applied force is called the '' mechanical advantage''. Simple machines can be regarded as the elementary "building blocks" of which all more complicated machines (sometimes called "compound machines") are composed. For example, wheels, levers, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inclined Plane
An inclined plane, also known as a ramp, is a flat supporting surface tilted at an angle from the vertical direction, with one end higher than the other, used as an aid for raising or lowering a load. The inclined plane is one of the six classical simple machines defined by Renaissance scientists. Inclined planes are used to move heavy loads over vertical obstacles. Examples vary from a ramp used to load goods into a truck, to a person walking up a pedestrian ramp, to an automobile or railroad train climbing a grade. Moving an object up an inclined plane requires less force than lifting it straight up, at a cost of an increase in the distance moved. The mechanical advantage of an inclined plane, the factor by which the force is reduced, is equal to the ratio of the length of the sloped surface to the height it spans. Owing to conservation of energy, the same amount of mechanical energy (work) is required to lift a given object by a given vertical distance, disregarding losse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanical Advantage
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. The device trades off input forces against movement to obtain a desired amplification in the output force. The model for this is the ''law of the lever.'' Machine components designed to manage forces and movement in this way are called mechanisms. An ideal mechanism transmits power without adding to or subtracting from it. This means the ideal machine does not include a power source, is frictionless, and is constructed from rigid bodies that do not deflect or wear. The performance of a real system relative to this ideal is expressed in terms of efficiency factors that take into account departures from the ideal. Lever The lever is a movable bar that pivots on a fulcrum attached to or positioned on or across a fixed point. The lever operates by applying forces at different distances from the fulcrum, or pivot. The location of the fulcrum determi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inclined Plane
An inclined plane, also known as a ramp, is a flat supporting surface tilted at an angle from the vertical direction, with one end higher than the other, used as an aid for raising or lowering a load. The inclined plane is one of the six classical simple machines defined by Renaissance scientists. Inclined planes are used to move heavy loads over vertical obstacles. Examples vary from a ramp used to load goods into a truck, to a person walking up a pedestrian ramp, to an automobile or railroad train climbing a grade. Moving an object up an inclined plane requires less force than lifting it straight up, at a cost of an increase in the distance moved. The mechanical advantage of an inclined plane, the factor by which the force is reduced, is equal to the ratio of the length of the sloped surface to the height it spans. Owing to conservation of energy, the same amount of mechanical energy (work) is required to lift a given object by a given vertical distance, disregarding losse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Six Mechanical Powers
6 is a number, numeral, and glyph. 6 or six may also refer to: * AD 6, the sixth year of the AD era * 6 BC, the sixth year before the AD era * The month of June Science * Carbon, the element with atomic number 6 * 6 Hebe, an asteroid People * Alphonse Six (1890–1914), Belgian football player * Didier Six (born 1954), former French international footballer * Franz Six (1909–1975), Nazi official * Frederick N. Six (born 1929), Justice of the Kansas Supreme Court * James Six (1731–1793), British scientist * Jan Six (1616-1700), an important cultural figure in the Dutch Golden Age * Robert Six (1907–1986), Chief Executive Officer of Continental Airlines between 1936 and 1981 * Regine Sixt, German businessperson * Valérie Six (born 1963), French politician * Perri 6 (an extremely rare surname), social scientist * Six family, family of regents of Amsterdam, founded by Jan Six Music * Six (band), an Irish pop band created by a TV reality show * ''Six'' (musical), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Industrial Revolution
The Industrial Revolution was the transition to new manufacturing processes in Great Britain, continental Europe, and the United States, that occurred during the period from around 1760 to about 1820–1840. This transition included going from hand production methods to machines, new chemical manufacturing and iron production processes, the increasing use of steam power and water power, the development of machine tools and the rise of the mechanized factory system. Output greatly increased, and a result was an unprecedented rise in population and in the rate of population growth. Textiles were the dominant industry of the Industrial Revolution in terms of employment, value of output and capital invested. The textile industry was also the first to use modern production methods. The Industrial Revolution began in Great Britain, and many of the technological and architectural innovations were of British origin. By the mid-18th century, Britain was the world's leadi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Screw
A screw and a bolt (see '' Differentiation between bolt and screw'' below) are similar types of fastener typically made of metal and characterized by a helical ridge, called a ''male thread'' (external thread). Screws and bolts are used to fasten materials by the engagement of the screw thread with a similar ''female thread'' (internal thread) in a matching part. Screws are often self-threading (also known as self-tapping) where the thread cuts into the material when the screw is turned, creating an internal thread that helps pull fastened materials together and prevents pull-out. There are many screws for a variety of materials; materials commonly fastened by screws include wood, sheet metal, and plastic. Explanation A screw is a combination of simple machines: it is, in essence, an inclined plane wrapped around a central shaft, but the inclined plane (thread) also comes to a sharp edge around the outside, which acts as a wedge as it pushes into the fastened material, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wedge (mechanical Device)
A wedge is a triangular shaped tool, and is a portable inclined plane, and one of the six simple machines. It can be used to separate two objects or portions of an object, lift up an object, or hold an object in place. It functions by converting a force applied to its blunt end into forces perpendicular ( normal) to its inclined surfaces. The mechanical advantage of a wedge is given by the ratio of the length of its slope to its width..''McGraw-Hill Concise Encyclopedia of Science & Technology'', Third Ed., Sybil P. Parker, ed., McGraw-Hill, Inc., 1992, p. 2041. Although a short wedge with a wide angle may do a job faster, it requires more force than a long wedge with a narrow angle. The force is applied on a flat, broad surface. This energy is transported to the pointy, sharp end of the wedge, hence the force is transported. The wedge simply transports energy in the form of friction and collects it to the pointy end, consequently breaking the item. History Wedges have ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulley
A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a taut cable or belt, or transfer of power between the shaft and cable or belt. In the case of a pulley supported by a frame or shell that does not transfer power to a shaft, but is used to guide the cable or exert a force, the supporting shell is called a block, and the pulley may be called a sheave. A pulley may have a groove or grooves between flanges around its circumference to locate the cable or belt. The drive element of a pulley system can be a rope, cable, belt, or chain. The earliest evidence of pulleys dates back to Ancient Egypt in the Twelfth Dynasty (1991-1802 BCE) and Mesopotamia in the early 2nd millennium BCE. In Roman Egypt, Hero of Alexandria (c. 10-70 CE) identified the pulley as one of six simple machines used to lift weights. Pulleys are assembled to form a block and tackle in order to provide mechanical advantage to apply large forces. Pulleys ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Windlass
The windlass is an apparatus for moving heavy weights. Typically, a windlass consists of a horizontal cylinder (barrel), which is rotated by the turn of a crank or belt. A winch is affixed to one or both ends, and a cable or rope is wound around the winch, pulling a weight attached to the opposite end. The Greek scientist Archimedes was the inventor of the windlass. The oldest depiction of a windlass for raising water can be found in the Book of Agriculture published in 1313 by the Chinese official Wang Zhen of the Yuan Dynasty ( 1290–1333). Uses *Vitruvius, a military engineer writing about 28 BC, defined a machine as "a combination of timber fastened together, chiefly efficacious in moving great weights." About a century later, Hero of Alexandria summarized the practice of his day by naming the "five simple machines" for "moving a given weight by a given force" as the lever, windlass, screw for power, wedge, and tackle block (pulley). Until nearly the end of the ninet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heron Of Alexandria
Hero of Alexandria (; grc-gre, Ἥρων ὁ Ἀλεξανδρεύς, ''Heron ho Alexandreus'', also known as Heron of Alexandria ; 60 AD) was a Greek mathematician and engineer who was active in his native city of Alexandria, Roman Egypt. He is often considered the greatest experimenter of antiquity and his work is representative of the Hellenistic scientific tradition. Hero published a well-recognized description of a steam-powered device called an ''aeolipile'' (sometimes called a "Hero engine"). Among his most famous inventions was a windwheel, constituting the earliest instance of wind harnessing on land. He is said to have been a follower of the atomists. In his work ''Mechanics'', he described pantographs. Some of his ideas were derived from the works of Ctesibius. In mathematics he is mostly remembered for Heron's formula, a way to calculate the area of a triangle using only the lengths of its sides. Much of Hero's original writings and designs have been lost, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pappus Of Alexandria
Pappus of Alexandria (; grc-gre, Πάππος ὁ Ἀλεξανδρεύς; AD) was one of the last great Greek mathematicians of antiquity known for his ''Synagoge'' (Συναγωγή) or ''Collection'' (), and for Pappus's hexagon theorem in projective geometry. Nothing is known of his life, other than what can be found in his own writings: that he had a son named Hermodorus, and was a teacher in Alexandria.Pierre Dedron, J. Itard (1959) ''Mathematics And Mathematicians'', Vol. 1, p. 149 (trans. Judith V. Field) (Transworld Student Library, 1974) ''Collection'', his best-known work, is a compendium of mathematics in eight volumes, the bulk of which survives. It covers a wide range of topics, including geometry, recreational mathematics, doubling the cube, polygons and polyhedra. Context Pappus was active in the 4th century AD. In a period of general stagnation in mathematical studies, he stands out as a remarkable exception. "How far he was above his contemporaries, how l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aristotelian Physics
Aristotelian physics is the form of natural science described in the works of the Greek philosopher Aristotle (384–322 BC). In his work ''Physics'', Aristotle intended to establish general principles of change that govern all natural bodies, both living and inanimate, celestial and terrestrialincluding all motion (change with respect to place), quantitative change (change with respect to size or number), qualitative change, and substantial change (" coming to be" oming into existence, 'generation'">existence.html" ;"title="oming into existence">oming into existence, 'generation'or "passing away" [no longer existing, 'corruption']). To Aristotle, 'physics' was a broad field that included subjects that would now be called the philosophy of mind, sensory experience, memory, anatomy and biology. It constitutes the foundation of the thought underlying many of his works. Key concepts of Aristotelian physics include the structuring of the cosmos into concentric spheres, with the Ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
