120-448: A machine is a physical system that uses power to apply forces and control movement to perform an action. The term is commonly applied to artificial devices, such as those employing engines or motors, but also to natural biological macromolecules, such as molecular machines . Machines can be driven by animals and people , by natural forces such as wind and water , and by chemical , thermal , or electrical power, and include
240-513: A motor is the product of the torque that the motor generates and the angular velocity of its output shaft. Likewise, the power dissipated in an electrical element of a circuit is the product of the current flowing through the element and of the voltage across the element. Power is the rate with respect to time at which work is done; it is the time derivative of work : P = d W d t , {\displaystyle P={\frac {dW}{dt}},} where P
360-502: A (near-) synonym both by Harris and in later language derives ultimately (via Old French ) from Latin ingenium 'ingenuity, an invention'. The hand axe , made by chipping flint to form a wedge , in the hands of a human transforms force and movement of the tool into a transverse splitting forces and movement of the workpiece. The hand axe is the first example of a wedge , the oldest of the six classic simple machines , from which most machines are based. The second oldest simple machine
480-426: A complicated and extensive syllabary. A considerable amount of Babylonian literature was translated from Sumerian originals, and the language of religion and law long continued to be the old agglutinative language of Sumer. Vocabularies, grammars, and interlinear translations were compiled for the use of students, as well as commentaries on the older texts and explanations of obscure words and phrases. The characters of
600-399: A force F A acting on a point that moves with velocity v A and the output power be a force F B acts on a point that moves with velocity v B . If there are no losses in the system, then P = F B v B = F A v A , {\displaystyle P=F_{\text{B}}v_{\text{B}}=F_{\text{A}}v_{\text{A}},} and
720-612: A language of the Zagros possibly related to the Hurro-Urartuan language family , is attested in personal names, rivers and mountains and in various crafts. Akkadian came to be the dominant language during the Akkadian Empire and the Assyrian empires, but Sumerian was retained for administrative, religious, literary and scientific purposes. Different varieties of Akkadian were used until
840-401: A lever is modeled as a hinged or revolute joint . Wheel: The wheel is an important early machine, such as the chariot . A wheel uses the law of the lever to reduce the force needed to overcome friction when pulling a load. To see this notice that the friction associated with pulling a load on the ground is approximately the same as the friction in a simple bearing that supports the load on
960-482: A logarithmic measure relative to a reference of 1 milliwatt, calories per hour, BTU per hour (BTU/h), and tons of refrigeration . As a simple example, burning one kilogram of coal releases more energy than detonating a kilogram of TNT , but because the TNT reaction releases energy more quickly, it delivers more power than the coal. If Δ W is the amount of work performed during a period of time of duration Δ t ,
1080-418: A machine is "a device for applying power or changing its direction."McCarthy and Soh describe a machine as a system that "generally consists of a power source and a mechanism for the controlled use of this power." Human and animal effort were the original power sources for early machines. Waterwheel: Waterwheels appeared around the world around 300 BC to use flowing water to generate rotary motion, which
1200-468: A machine provides a way to understand the performance of devices ranging from levers and gear trains to automobiles and robotic systems. The German mechanician Franz Reuleaux wrote, "a machine is a combination of resistant bodies so arranged that by their means the mechanical forces of nature can be compelled to do work accompanied by certain determinate motion." Notice that forces and motion combine to define power . More recently, Uicker et al. stated that
1320-836: A mechanical system is assembled from components called machine elements . These elements provide structure for the system and control its movement. The structural components are, generally, the frame members, bearings, splines, springs, seals, fasteners and covers. The shape, texture and color of covers provide a styling and operational interface between the mechanical system and its users. The assemblies that control movement are also called " mechanisms ." Mechanisms are generally classified as gears and gear trains , which includes belt drives and chain drives , cam and follower mechanisms, and linkages , though there are other special mechanisms such as clamping linkages, indexing mechanisms , escapements and friction devices such as brakes and clutches . The number of degrees of freedom of
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#17331071699421440-500: A mechanism, or its mobility, depends on the number of links and joints and the types of joints used to construct the mechanism. The general mobility of a mechanism is the difference between the unconstrained freedom of the links and the number of constraints imposed by the joints. It is described by the Chebychev–Grübler–Kutzbach criterion . The transmission of rotation between contacting toothed wheels can be traced back to
1560-482: A patient could not be cured physically, the Babylonian physicians often relied on exorcism to cleanse the patient from any curses . Esagil-kin-apli's Diagnostic Handbook was based on a logical set of axioms and assumptions, including the modern view that through the examination and inspection of the symptoms of a patient, it is possible to determine the patient's disease , its aetiology, its future development, and
1680-420: A periodic function of period T {\displaystyle T} . The peak power is simply defined by: P 0 = max [ p ( t ) ] . {\displaystyle P_{0}=\max[p(t)].} The peak power is not always readily measurable, however, and the measurement of the average power P a v g {\displaystyle P_{\mathrm {avg} }}
1800-412: A point farther from the pivot is greater than the velocity of a point near the pivot, forces applied far from the pivot are amplified near the pivot by the associated decrease in speed. If a is the distance from the pivot to the point where the input force is applied and b is the distance to the point where the output force is applied, then a/b is the mechanical advantage of the lever. The fulcrum of
1920-549: A precursor to the Socratic method . The Ionian philosopher Thales was influenced by Babylonian cosmological ideas. Ancient Mesopotamians had ceremonies each month. The theme of the rituals and festivals for each month was determined by at least six important factors: Some songs were written for the gods but many were written to describe important events. Although music and songs amused kings , they were also enjoyed by ordinary people who liked to sing and dance in their homes or in
2040-430: A pressure vessel; the expanding steam drives a piston or a turbine. This principle can be seen in the aeolipile of Hero of Alexandria. This is called an external combustion engine . An automobile engine is called an internal combustion engine because it burns fuel (an exothermic chemical reaction) inside a cylinder and uses the expanding gases to drive a piston . A jet engine uses a turbine to compress air which
2160-519: A programmable drum machine , where they could be made to play different rhythms and different drum patterns. During the Renaissance , the dynamics of the Mechanical Powers , as the simple machines were called, began to be studied from the standpoint of how much useful work they could perform, leading eventually to the new concept of mechanical work . In 1586 Flemish engineer Simon Stevin derived
2280-730: A recent hypothesis, the Archimedes' screw may have been used by Sennacherib, King of Assyria, for the water systems at the Hanging Gardens of Babylon and Nineveh in the 7th century BC, although mainstream scholarship holds it to be a Greek invention of later times. Later, during the Parthian or Sasanian periods, the Baghdad Battery , which may have been the world's first battery, was created in Mesopotamia. The Ancient Mesopotamian religion
2400-550: A sacred, ceremonial, literary, and scientific language in Mesopotamia until the 1st century AD. Libraries were extant in towns and temples during the Babylonian Empire. An old Sumerian proverb averred that "he who would excel in the school of the scribes must rise with the dawn." Women as well as men learned to read and write, and for the Semitic Babylonians, this involved knowledge of the extinct Sumerian language, and
2520-414: A simple balance scale , and to move large objects in ancient Egyptian technology . The lever was also used in the shadoof water-lifting device, the first crane machine, which appeared in Mesopotamia c. 3000 BC , and then in ancient Egyptian technology c. 2000 BC . The earliest evidence of pulleys date back to Mesopotamia in the early 2nd millennium BC, and ancient Egypt during
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#17331071699422640-455: A specific application of output forces and movement, (iii) a controller with sensors that compare the output to a performance goal and then directs the actuator input, and (iv) an interface to an operator consisting of levers, switches, and displays. This can be seen in Watt's steam engine in which the power is provided by steam expanding to drive the piston. The walking beam, coupler and crank transform
2760-645: A system of mechanisms that shape the actuator input to achieve a specific application of output forces and movement. They can also include computers and sensors that monitor performance and plan movement, often called mechanical systems . Renaissance natural philosophers identified six simple machines which were the elementary devices that put a load into motion, and calculated the ratio of output force to input force, known today as mechanical advantage . Modern machines are complex systems that consist of structural elements, mechanisms and control components and include interfaces for convenient use. Examples include:
2880-415: A table of Pythagorean triples and represents some of the most advanced mathematics prior to Greek mathematics. From Sumerian times, temple priesthoods had attempted to associate current events with certain positions of the planets and stars. This continued to Assyrian times, when Limmu lists were created as a year by year association of events with planetary positions, which, when they have survived to
3000-510: A vast mountainous region. Overland routes in Mesopotamia usually follow the Euphrates because the banks of the Tigris are frequently steep and difficult. The climate of the region is semi-arid with a vast desert expanse in the north which gives way to a 15,000-square-kilometre (5,800 sq mi) region of marshes, lagoons, mudflats, and reed banks in the south. In the extreme south, the Euphrates and
3120-402: A wide range of vehicles , such as trains , automobiles , boats and airplanes ; appliances in the home and office, including computers, building air handling and water handling systems ; as well as farm machinery , machine tools and factory automation systems and robots . The English word machine comes through Middle French from Latin machina , which in turn derives from
3240-580: Is an-ki , which refers to the god An and the goddess Ki . Their son was Enlil, the air god. They believed that Enlil was the most powerful god. He was the chief god of the pantheon . The numerous civilizations of the area influenced the Abrahamic religions , especially the Hebrew Bible . Its cultural values and literary influence are especially evident in the Book of Genesis . Giorgio Buccellati believes that
3360-414: Is a composite product, although it is probable that some of the stories are artificially attached to the central figure. Mesopotamian mathematics and science was based on a sexagesimal (base 60) numeral system . This is the source of the 60-minute hour, the 24-hour day, and the 360- degree circle. The Sumerian calendar was lunisolar, with three seven-day weeks of a lunar month. This form of mathematics
3480-464: Is accurate to about six decimal digits, and is the closest possible three-place sexagesimal representation of √ 2 : The Babylonians were not interested in exact solutions, but rather approximations, and so they would commonly use linear interpolation to approximate intermediate values. One of the most famous tablets is the Plimpton 322 tablet , created around 1900–1600 BC, which gives
3600-409: Is burned with fuel so that it expands through a nozzle to provide thrust to an aircraft , and so is also an "internal combustion engine." Power plant: The heat from coal and natural gas combustion in a boiler generates steam that drives a steam turbine to rotate an electric generator . A nuclear power plant uses heat from a nuclear reactor to generate steam and electric power . This power
3720-423: Is called the cam (also see cam shaft ) and the link that is driven through the direct contact of their surfaces is called the follower. The shape of the contacting surfaces of the cam and follower determines the movement of the mechanism. A linkage is a collection of links connected by joints. Generally, the links are the structural elements and the joints allow movement. Perhaps the single most useful example
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3840-580: Is compatible with ergodic axioms. Logic was employed to some extent in Babylonian astronomy and medicine. Babylonian thought had a considerable influence on early Ancient Greek and Hellenistic philosophy . In particular, the Babylonian text Dialogue of Pessimism contains similarities to the agonistic thought of the Sophists , the Heraclitean doctrine of dialectic , and the dialogs of Plato , as well as
3960-412: Is constant, the amount of work performed in time period t can be calculated as W = P t . {\displaystyle W=Pt.} In the context of energy conversion, it is more customary to use the symbol E rather than W . Power in mechanical systems is the combination of forces and movement. In particular, power is the product of a force on an object and the object's velocity, or
4080-602: Is distributed through a network of transmission lines for industrial and individual use. Motors: Electric motors use either AC or DC electric current to generate rotational movement. Electric servomotors are the actuators for mechanical systems ranging from robotic systems to modern aircraft . Fluid Power: Hydraulic and pneumatic systems use electrically driven pumps to drive water or air respectively into cylinders to power linear movement . Electrochemical: Chemicals and materials can also be sources of power. They may chemically deplete or need re-charging, as
4200-449: Is given by P ( t ) = p Q , {\displaystyle P(t)=pQ,} where p is pressure in pascals or N/m , and Q is volumetric flow rate in m /s in SI units. If a mechanical system has no losses, then the input power must equal the output power. This provides a simple formula for the mechanical advantage of the system. Let the input power to a device be
4320-401: Is made by chipping stone, generally flint, to form a bifacial edge, or wedge . A wedge is a simple machine that transforms lateral force and movement of the tool into a transverse splitting force and movement of the workpiece. The available power is limited by the effort of the person using the tool, but because power is the product of force and movement, the wedge amplifies the force by reducing
4440-675: Is more commonly performed by an instrument. If one defines the energy per pulse as ε p u l s e = ∫ 0 T p ( t ) d t {\displaystyle \varepsilon _{\mathrm {pulse} }=\int _{0}^{T}p(t)\,dt} then the average power is P a v g = 1 T ∫ 0 T p ( t ) d t = ε p u l s e T . {\displaystyle P_{\mathrm {avg} }={\frac {1}{T}}\int _{0}^{T}p(t)\,dt={\frac {\varepsilon _{\mathrm {pulse} }}{T}}.} One may define
4560-414: Is power, W is work, and t is time. We will now show that the mechanical power generated by a force F on a body moving at the velocity v can be expressed as the product: P = d W d t = F ⋅ v {\displaystyle P={\frac {dW}{dt}}=\mathbf {F} \cdot \mathbf {v} } If a constant force F is applied throughout a distance x ,
4680-401: Is the electrical resistance , measured in ohms . In the case of a periodic signal s ( t ) {\displaystyle s(t)} of period T {\displaystyle T} , like a train of identical pulses, the instantaneous power p ( t ) = | s ( t ) | 2 {\textstyle p(t)=|s(t)|^{2}} is also
4800-414: Is the case with batteries , or they may produce power without changing their state, which is the case for solar cells and thermoelectric generators . All of these, however, still require their energy to come from elsewhere. With batteries, it is the already existing chemical potential energy inside. In solar cells and thermoelectrics, the energy source is light and heat respectively. The mechanism of
4920-499: Is the limiting value of the average power as the time interval Δ t approaches zero. P = lim Δ t → 0 P a v g = lim Δ t → 0 Δ W Δ t = d W d t . {\displaystyle P=\lim _{\Delta t\to 0}P_{\mathrm {avg} }=\lim _{\Delta t\to 0}{\frac {\Delta W}{\Delta t}}={\frac {dW}{dt}}.} When power P
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5040-421: Is the planar four-bar linkage . However, there are many more special linkages: A planar mechanism is a mechanical system that is constrained so the trajectories of points in all the bodies of the system lie on planes parallel to a ground plane. The rotational axes of hinged joints that connect the bodies in the system are perpendicular to this ground plane. A spherical mechanism is a mechanical system in which
5160-465: Is the product of the torque τ and angular velocity ω , P ( t ) = τ ⋅ ω , {\displaystyle P(t)={\boldsymbol {\tau }}\cdot {\boldsymbol {\omega }},} where ω is angular frequency , measured in radians per second . The ⋅ {\displaystyle \cdot } represents scalar product . In fluid power systems such as hydraulic actuators, power
5280-421: Is uncertain. The Babylonian development of methods for predicting the motions of the planets is considered to be a major episode in the history of astronomy . The only Greek-Babylonian astronomer known to have supported a heliocentric model of planetary motion was Seleucus of Seleucia (b. 190 BC). Seleucus is known from the writings of Plutarch . He supported Aristarchus of Samos' heliocentric theory where
5400-510: The Antikythera mechanism of Greece and the south-pointing chariot of China . Illustrations by the renaissance scientist Georgius Agricola show gear trains with cylindrical teeth. The implementation of the involute tooth yielded a standard gear design that provides a constant speed ratio. Some important features of gears and gear trains are: A cam and follower is formed by the direct contact of two specially shaped links. The driving link
5520-663: The Earth rotated around its own axis which in turn revolved around the Sun . According to Plutarch , Seleucus even proved the heliocentric system, but it is not known what arguments he used, except that he correctly theorized on tides as a result of the Moon's attraction. Babylonian astronomy served as the basis for much of Greek , classical Indian , Sassanian, Byzantine , Syrian , medieval Islamic , Central Asian , and Western European astronomy. The oldest Babylonian texts on medicine date back to
5640-506: The Greek ( Doric μαχανά makhana , Ionic μηχανή mekhane 'contrivance, machine, engine', a derivation from μῆχος mekhos 'means, expedient, remedy'). The word mechanical (Greek: μηχανικός ) comes from the same Greek roots. A wider meaning of 'fabric, structure' is found in classical Latin, but not in Greek usage. This meaning is found in late medieval French, and is adopted from
5760-470: The International System of Units , the unit of power is the watt , equal to one joule per second. Power is a scalar quantity. Specifying power in particular systems may require attention to other quantities; for example, the power involved in moving a ground vehicle is the product of the aerodynamic drag plus traction force on the wheels, and the velocity of the vehicle. The output power of
5880-599: The Jazira , is the area between the Euphrates and the Tigris from their sources down to Baghdad . Lower Mesopotamia is the area from Baghdad to the Persian Gulf and includes Kuwait and parts of western Iran. In modern academic usage, the term Mesopotamia often also has a chronological connotation. It is usually used to designate the area until the Muslim conquests , with names like Syria , Jazira , and Iraq being used to describe
6000-657: The Neo-Assyrian Empire asserted control over much of the ancient Near East. Subsequently, the Babylonians, who had long been overshadowed by Assyria, seized power , dominating the region for a century as the final independent Mesopotamian realm until the modern era. In 539 BC, Mesopotamia was conquered by the Achaemenid Empire . The area was next conquered by Alexander the Great in 332 BC. After his death, it became part of
6120-634: The Old Babylonian period in the first half of the 2nd millennium BC . The most extensive Babylonian medical text, however, is the Diagnostic Handbook written by the ummânū , or chief scholar, Esagil-kin-apli of Borsippa , during the reign of the Babylonian king Adad-apla-iddina (1069–1046 BC). Along with contemporary Egyptian medicine , the Babylonians introduced the concepts of diagnosis , prognosis , physical examination , enemas , and prescriptions . The Diagnostic Handbook introduced
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#17331071699426240-611: The Tigris–Euphrates river system , in the northern part of the Fertile Crescent . Today, Mesopotamia is known as present-day Iraq . In the broader sense, the historical region of Mesopotamia also includes parts of present-day Iran , Turkey , Syria and Kuwait . Mesopotamia is the site of the earliest developments of the Neolithic Revolution from around 10,000 BC. It has been identified as having "inspired some of
6360-581: The Twelfth Dynasty (1991–1802 BC). The screw , the last of the simple machines to be invented, first appeared in Mesopotamia during the Neo-Assyrian period (911–609) BC. The Egyptian pyramids were built using three of the six simple machines, the inclined plane, the wedge, and the lever. Three of the simple machines were studied and described by Greek philosopher Archimedes around the 3rd century BC:
6480-410: The duty cycle of the pulse train. Power is related to intensity at a radius r {\displaystyle r} ; the power emitted by a source can be written as: P ( r ) = I ( 4 π r 2 ) . {\displaystyle P(r)=I(4\pi r^{2}).} Mesopotamia Mesopotamia is a historical region of West Asia situated within
6600-402: The fall of Babylon in 539 BC. The rise of empires, beginning with Sargon of Akkad around 2350 BC, characterized the subsequent 2,000 years of Mesopotamian history, marked by the succession of kingdoms and empires such as the Akkadian Empire . The early second millennium BC saw the polarization of Mesopotamian society into Assyria in the north and Babylonia in the south. From 900 to 612 BC,
6720-414: The fundamental theorem of calculus , we know that P = d W d t = d d t ∫ Δ t F ⋅ v d t = F ⋅ v . {\displaystyle P={\frac {dW}{dt}}={\frac {d}{dt}}\int _{\Delta t}\mathbf {F} \cdot \mathbf {v} \,dt=\mathbf {F} \cdot \mathbf {v} .} Hence
6840-491: The lever , pulley and screw as simple machines . By the time of the Renaissance this list increased to include the wheel and axle , wedge and inclined plane . The modern approach to characterizing machines focusses on the components that allow movement, known as joints . Wedge (hand axe): Perhaps the first example of a device designed to manage power is the hand axe , also called biface and Olorgesailie . A hand axe
6960-438: The marketplaces . Songs were sung to children who passed them on to their children. Thus songs were passed on through many generations as an oral tradition until writing was more universal. These songs provided a means of passing on through the centuries highly important information about historical events. Hunting was popular among Assyrian kings. Boxing and wrestling feature frequently in art, and some form of polo
7080-424: The mechanical advantage of the system (output force per input force) is given by M A = F B F A = v A v B . {\displaystyle \mathrm {MA} ={\frac {F_{\text{B}}}{F_{\text{A}}}}={\frac {v_{\text{A}}}{v_{\text{B}}}}.} The similar relationship is obtained for rotating systems, where T A and ω A are
7200-407: The É , a temple dedicated to the goddess Inanna at Uruk, from a building labeled as Temple C by its excavators. The early logographic system of cuneiform script took many years to master. Thus, only a limited number of individuals were hired as scribes to be trained in its use. It was not until the widespread use of a syllabic script was adopted under Sargon's rule that significant portions of
7320-679: The (two) rivers") comes from the ancient Greek root words μέσος ( mesos , 'middle') and ποταμός ( potamos , 'river') and translates to '(land) between rivers', likely being a calque of the older Aramaic term, with the Aramaic term itself likely being a calque of the Akkadian birit narim . It is used throughout the Greek Septuagint ( c. 250 BC ) to translate the Hebrew and Aramaic equivalent Naharaim . An even earlier Greek usage of
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#17331071699427440-813: The 7th century Muslim conquest of Persia of the Sasanian Empire and the Muslim conquest of the Levant from the Byzantines. A number of primarily neo-Assyrian and Christian native Mesopotamian states existed between the 1st century BC and 3rd century AD, including Adiabene , Osroene , and Hatra . The regional toponym Mesopotamia ( / ˌ m ɛ s ə p ə ˈ t eɪ m i ə / , Ancient Greek : Μεσοποταμία '[land] between rivers'; Arabic : بِلَاد ٱلرَّافِدَيْن Bilād ar-Rāfidayn or بَيْن ٱلنَّهْرَيْن Bayn an-Nahrayn ; Persian : میانرودان miyân rudân ; Syriac : ܒܝܬ ܢܗܪ̈ܝܢ Beth Nahrain "(land) between
7560-532: The 8,000-year-old remains of early farmers found at an ancient graveyard in Germany . They compared the genetic signatures to those of modern populations and found similarities with the DNA of people living in today's Turkey and Iraq . The earliest language written in Mesopotamia was Sumerian , an agglutinative language isolate . Along with Sumerian, Semitic languages were also spoken in early Mesopotamia. Subartuan ,
7680-547: The French into English in the mid-16th century. In the 17th century, the word machine could also mean a scheme or plot, a meaning now expressed by the derived machination . The modern meaning develops out of specialized application of the term to stage engines used in theater and to military siege engines , both in the late 16th and early 17th centuries. The OED traces the formal, modern meaning to John Harris ' Lexicon Technicum (1704), which has: The word engine used as
7800-778: The Greek Seleucid Empire . Around 150 BC, Mesopotamia was under the control of the Parthian Empire . It became a battleground between the Romans and Parthians, with western parts of the region coming under ephemeral Roman control. In 226 AD, the eastern regions of Mesopotamia fell to the Sassanid Persians . The division of the region between the Roman Byzantine Empire from 395 AD and the Sassanid Empire lasted until
7920-553: The Greeks' understanding was limited to statics (the balance of forces) and did not include dynamics (the tradeoff between force and distance) or the concept of work . The earliest practical wind-powered machines, the windmill and wind pump , first appeared in the Muslim world during the Islamic Golden Age , in what are now Iran, Afghanistan, and Pakistan, by the 9th century AD. The earliest practical steam-powered machine
8040-467: The Mesopotamian population became literate. Massive archives of texts were recovered from the archaeological contexts of Old Babylonian scribal schools, through which literacy was disseminated. Akkadian gradually replaced Sumerian as the spoken language of Mesopotamia somewhere around the turn of the 3rd and the 2nd millennium BC. The exact dating being a matter of debate. Sumerian continued to be used as
8160-522: The Muslim world. A music sequencer , a programmable musical instrument , was the earliest type of programmable machine. The first music sequencer was an automated flute player invented by the Banu Musa brothers, described in their Book of Ingenious Devices , in the 9th century. In 1206, Al-Jazari invented programmable automata / robots . He described four automaton musicians, including drummers operated by
8280-464: The Tigris unite and empty into the Persian Gulf . The arid environment ranges from the northern areas of rain-fed agriculture to the south where irrigation of agriculture is essential. This irrigation is aided by a high water table and by melting snows from the high peaks of the northern Zagros Mountains and from the Armenian Highlands, the source of the Tigris and Euphrates Rivers that give
8400-498: The ancient history of lower Mesopotamia—commenced in the early-third millennium BC with cuneiform records of early dynastic kings. This entire history ends with either the arrival of the Achaemenid Empire in the late 6th century BC or with the Muslim conquest and the establishment of the Caliphate in the late 7th century AD, from which point the region came to be known as Iraq . In the long span of this period, Mesopotamia housed some of
8520-421: The average power P avg over that period is given by the formula P a v g = Δ W Δ t . {\displaystyle P_{\mathrm {avg} }={\frac {\Delta W}{\Delta t}}.} It is the average amount of work done or energy converted per unit of time. Average power is often called "power" when the context makes it clear. Instantaneous power
8640-408: The axle of a wheel. However, the wheel forms a lever that magnifies the pulling force so that it overcomes the frictional resistance in the bearing. The classification of simple machines to provide a strategy for the design of new machines was developed by Franz Reuleaux , who collected and studied over 800 elementary machines. He recognized that the classical simple machines can be separated into
8760-583: The beginning and end of the path along which the work was done. The power at any point along the curve C is the time derivative: P ( t ) = d W d t = F ⋅ v = − d U d t . {\displaystyle P(t)={\frac {dW}{dt}}=\mathbf {F} \cdot \mathbf {v} =-{\frac {dU}{dt}}.} In one dimension, this can be simplified to: P ( t ) = F ⋅ v . {\displaystyle P(t)=F\cdot v.} In rotational systems, power
8880-420: The bodies in the system form lines in space that do not intersect and have distinct common normals. A flexure mechanism consists of a series of rigid bodies connected by compliant elements (also known as flexure joints) that is designed to produce a geometrically well-defined motion upon application of a force. Power (physics) Power is the amount of energy transferred or converted per unit time. In
9000-411: The bodies move in a way that the trajectories of points in the system lie on concentric spheres. The rotational axes of hinged joints that connect the bodies in the system pass through the center of these circle. A spatial mechanism is a mechanical system that has at least one body that moves in a way that its point trajectories are general space curves. The rotational axes of hinged joints that connect
9120-410: The chances of the patient's recovery. Esagil-kin-apli discovered a variety of illnesses and diseases and described their symptoms in his Diagnostic Handbook . These include the symptoms for many varieties of epilepsy and related ailments along with their diagnosis and prognosis. Some treatments used were likely based off the known characteristics of the ingredients used. The others were based on
9240-696: The city of Eridu , the Akkadian kingdoms, the Third Dynasty of Ur , and the various Assyrian empires. Some of the important historical Mesopotamian leaders were Ur-Nammu (king of Ur), Sargon of Akkad (who established the Akkadian Empire), Hammurabi (who established the Old Babylonian state), Ashur-uballit I and Tiglath-Pileser I (who established the Assyrian Empire). Scientists analysed DNA from
9360-614: The cultural mix. Periodic breakdowns in the cultural system have occurred for a number of reasons. The demands for labor has from time to time led to population increases that push the limits of the ecological carrying capacity , and should a period of climatic instability ensue, collapsing central government and declining populations can occur. Alternatively, military vulnerability to invasion from marginal hill tribes or nomadic pastoralists has led to periods of trade collapse and neglect of irrigation systems. Equally, centripetal tendencies amongst city-states have meant that central authority over
9480-421: The cycles of the moon. They divided the year into two seasons: summer and winter. The origins of astronomy as well as astrology date from this time. During the 8th and 7th centuries BC, Babylonian astronomers developed a new approach to astronomy. They began studying philosophy dealing with the ideal nature of the early universe and began employing an internal logic within their predictive planetary systems. This
9600-570: The double acting steam engine practical. The Boulton and Watt steam engine and later designs powered steam locomotives , steam ships , and factories . The Industrial Revolution was a period from 1750 to 1850 where changes in agriculture, manufacturing, mining, transportation, and technology had a profound effect on the social, economic and cultural conditions of the times. It began in the United Kingdom , then subsequently spread throughout Western Europe , North America , Japan , and eventually
9720-471: The end of the Neo-Babylonian period. Old Aramaic , which had already become common in Mesopotamia, then became the official provincial administration language of first the Neo-Assyrian Empire , and then the Achaemenid Empire : the official lect is called Imperial Aramaic . Akkadian fell into disuse, but both it and Sumerian were still used in temples for some centuries. The last Akkadian texts date from
9840-611: The force is variable over a three-dimensional curve C , then the work is expressed in terms of the line integral: W = ∫ C F ⋅ d r = ∫ Δ t F ⋅ d r d t d t = ∫ Δ t F ⋅ v d t . {\displaystyle W=\int _{C}\mathbf {F} \cdot d\mathbf {r} =\int _{\Delta t}\mathbf {F} \cdot {\frac {d\mathbf {r} }{dt}}\ dt=\int _{\Delta t}\mathbf {F} \cdot \mathbf {v} \,dt.} From
9960-523: The formula is valid for any general situation. In older works, power is sometimes called activity . The dimension of power is energy divided by time. In the International System of Units (SI), the unit of power is the watt (W), which is equal to one joule per second. Other common and traditional measures are horsepower (hp), comparing to the power of a horse; one mechanical horsepower equals about 745.7 watts. Other units of power include ergs per second (erg/s), foot-pounds per minute, dBm ,
10080-460: The late 1st century AD. Early in Mesopotamia's history, around the mid-4th millennium BC, cuneiform was invented for the Sumerian language. Cuneiform literally means "wedge-shaped", due to the triangular tip of the stylus used for impressing signs on wet clay. The standardized form of each cuneiform sign appears to have been developed from pictograms . The earliest texts, 7 archaic tablets, come from
10200-490: The lever, pulley and screw. Archimedes discovered the principle of mechanical advantage in the lever. Later Greek philosophers defined the classic five simple machines (excluding the inclined plane) and were able to roughly calculate their mechanical advantage. Hero of Alexandria ( c. 10 –75 AD) in his work Mechanics lists five mechanisms that can "set a load in motion"; lever, windlass , pulley, wedge, and screw, and describes their fabrication and uses. However,
10320-416: The lever, pulley and wheel and axle that are formed by a body rotating about a hinge, and the inclined plane, wedge and screw that are similarly a block sliding on a flat surface. Simple machines are elementary examples of kinematic chains or linkages that are used to model mechanical systems ranging from the steam engine to robot manipulators. The bearings that form the fulcrum of a lever and that allow
10440-527: The linear movement of the piston into rotation of the output pulley. Finally, the pulley rotation drives the flyball governor which controls the valve for the steam input to the piston cylinder. The adjective "mechanical" refers to skill in the practical application of an art or science, as well as relating to or caused by movement, physical forces, properties or agents such as is dealt with by mechanics . Similarly Merriam-Webster Dictionary defines "mechanical" as relating to machinery or tools. Power flow through
10560-731: The maximum performance of a device in terms of velocity ratios determined by its physical dimensions. See for example gear ratios . The instantaneous electrical power P delivered to a component is given by P ( t ) = I ( t ) ⋅ V ( t ) , {\displaystyle P(t)=I(t)\cdot V(t),} where If the component is a resistor with time-invariant voltage to current ratio, then: P = I ⋅ V = I 2 ⋅ R = V 2 R , {\displaystyle P=I\cdot V=I^{2}\cdot R={\frac {V^{2}}{R}},} where R = V I {\displaystyle R={\frac {V}{I}}}
10680-747: The mechanical advantage of the inclined plane, and it was included with the other simple machines. The complete dynamic theory of simple machines was worked out by Italian scientist Galileo Galilei in 1600 in Le Meccaniche ("On Mechanics"). He was the first to understand that simple machines do not create energy , they merely transform it. The classic rules of sliding friction in machines were discovered by Leonardo da Vinci (1452–1519), but remained unpublished in his notebooks. They were rediscovered by Guillaume Amontons (1699) and were further developed by Charles-Augustin de Coulomb (1785). James Watt patented his parallel motion linkage in 1782, which made
10800-472: The methods of therapy and aetiology and the use of empiricism , logic , and rationality in diagnosis, prognosis and therapy. The text contains a list of medical symptoms and often detailed empirical observations along with logical rules used in combining observed symptoms on the body of a patient with its diagnosis and prognosis. The symptoms and diseases of a patient were treated through therapeutic means such as bandages , creams and pills . If
10920-462: The most important developments in human history, including the invention of the wheel , the planting of the first cereal crops , the development of cursive script, mathematics , astronomy , and agriculture ". It is recognised as the cradle of some of the world's earliest civilizations. The Sumerians and Akkadians , each originating from different areas, dominated Mesopotamia from the beginning of recorded history ( c. 3100 BC ) to
11040-408: The movement. This amplification, or mechanical advantage is the ratio of the input speed to output speed. For a wedge this is given by 1/tanα, where α is the tip angle. The faces of a wedge are modeled as straight lines to form a sliding or prismatic joint . Lever: The lever is another important and simple device for managing power. This is a body that pivots on a fulcrum. Because the velocity of
11160-520: The name Mesopotamia is evident from The Anabasis of Alexander , which was written in the late 2nd century AD but specifically refers to sources from the time of Alexander the Great . In the Anabasis , Mesopotamia was used to designate the land east of the Euphrates in north Syria . The Akkadian term biritum/birit narim corresponded to a similar geographical concept. Later, the term Mesopotamia
11280-420: The origins of philosophy can be traced back to early Mesopotamian wisdom , which embodied certain philosophies of life, particularly ethics , in the forms of dialectic , dialogues , epic poetry , folklore , hymns , lyrics , prose works, and proverbs . Babylonian reason and rationality developed beyond empirical observation. Babylonian thought was also based on an open-systems ontology which
11400-418: The output of one crank to the input of another. Additional links can be attached to form a six-bar linkage or in series to form a robot. A mechanical system manages power to accomplish a task that involves forces and movement. Modern machines are systems consisting of (i) a power source and actuators that generate forces and movement, (ii) a system of mechanisms that shape the actuator input to achieve
11520-414: The path C and v is the velocity along this path. If the force F is derivable from a potential ( conservative ), then applying the gradient theorem (and remembering that force is the negative of the gradient of the potential energy) yields: W C = U ( A ) − U ( B ) , {\displaystyle W_{C}=U(A)-U(B),} where A and B are
11640-402: The present day, allow accurate associations of relative with absolute dating for establishing the history of Mesopotamia. The Babylonian astronomers were very adept at mathematics and could predict eclipses and solstices . Scholars thought that everything had some purpose in astronomy. Most of these related to religion and omens. Mesopotamian astronomers worked out a 12-month calendar based on
11760-402: The primary elements of a machine. Starting with four types of joints, the rotary joint, sliding joint, cam joint and gear joint, and related connections such as cables and belts, it is possible to understand a machine as an assembly of solid parts that connect these joints called a mechanism . Two levers, or cranks, are combined into a planar four-bar linkage by attaching a link that connects
11880-580: The product of a torque on a shaft and the shaft's angular velocity. Mechanical power is also described as the time derivative of work. In mechanics , the work done by a force F on an object that travels along a curve C is given by the line integral : W C = ∫ C F ⋅ v d t = ∫ C F ⋅ d x , {\displaystyle W_{C}=\int _{C}\mathbf {F} \cdot \mathbf {v} \,dt=\int _{C}\mathbf {F} \cdot d\mathbf {x} ,} where x defines
12000-488: The pulse length τ {\displaystyle \tau } such that P 0 τ = ε p u l s e {\displaystyle P_{0}\tau =\varepsilon _{\mathrm {pulse} }} so that the ratios P a v g P 0 = τ T {\displaystyle {\frac {P_{\mathrm {avg} }}{P_{0}}}={\frac {\tau }{T}}} are equal. These ratios are called
12120-425: The region after that date. It has been argued that these later euphemisms are Eurocentric terms attributed to the region in the midst of various 19th-century Western encroachments. Mesopotamia encompasses the land between the Euphrates and Tigris rivers, both of which have their headwaters in the neighboring Armenian highlands . Both rivers are fed by numerous tributaries, and the entire river system drains
12240-441: The region its name. The usefulness of irrigation depends upon the ability to mobilize sufficient labor for the construction and maintenance of canals, and this, from the earliest period, has assisted the development of urban settlements and centralized systems of political authority. Agriculture throughout the region has been supplemented by nomadic pastoralism, where tent-dwelling nomads herded sheep and goats (and later camels) from
12360-466: The rest of the world. Starting in the later part of the 18th century, there began a transition in parts of Great Britain 's previously manual labour and draft-animal-based economy towards machine-based manufacturing. It started with the mechanisation of the textile industries, the development of iron-making techniques and the increased use of refined coal . The idea that a machine can be decomposed into simple movable elements led Archimedes to define
12480-461: The river pastures in the dry summer months, out into seasonal grazing lands on the desert fringe in the wet winter season. The area is generally lacking in building stone, precious metals, and timber, and so historically has relied upon long-distance trade of agricultural products to secure these items from outlying areas. In the marshlands to the south of the area, a complex water-borne fishing culture has existed since prehistoric times and has added to
12600-534: The syllabary were all arranged and named, and elaborate lists were drawn up. Many Babylonian literary works are still studied today. One of the most famous of these was the Epic of Gilgamesh , in twelve books, translated from the original Sumerian by a certain Sîn-lēqi-unninni , and arranged upon an astronomical principle. Each division contains the story of a single adventure in the career of Gilgamesh . The whole story
12720-550: The symbolic qualities. Mesopotamian people invented many technologies including metal and copper-working, glass and lamp making, textile weaving, flood control , water storage, and irrigation. They were also one of the first Bronze Age societies in the world. They developed from copper, bronze, and gold on to iron. Palaces were decorated with hundreds of kilograms of these very expensive metals. Also, copper, bronze, and iron were used for armor as well as for different weapons such as swords, daggers, spears, and maces . According to
12840-744: The torque and angular velocity of the input and T B and ω B are the torque and angular velocity of the output. If there are no losses in the system, then P = T A ω A = T B ω B , {\displaystyle P=T_{\text{A}}\omega _{\text{A}}=T_{\text{B}}\omega _{\text{B}},} which yields the mechanical advantage M A = T B T A = ω A ω B . {\displaystyle \mathrm {MA} ={\frac {T_{\text{B}}}{T_{\text{A}}}}={\frac {\omega _{\text{A}}}{\omega _{\text{B}}}}.} These relations are important because they define
12960-418: The volume of the frustum of a cone or a square pyramid was incorrectly taken as the product of the height and half the sum of the bases. Also, there was a recent discovery in which a tablet used π as 25/8 (3.125 instead of 3.14159~). The Babylonians are also known for the Babylonian mile, which was a measure of distance equal to about seven modern miles (11 km). This measurement for distances eventually
13080-399: The wheel and axle and pulleys to rotate are examples of a kinematic pair called a hinged joint. Similarly, the flat surface of an inclined plane and wedge are examples of the kinematic pair called a sliding joint. The screw is usually identified as its own kinematic pair called a helical joint. This realization shows that it is the joints, or the connections that provide movement, that are
13200-679: The whole region, when imposed, has tended to be ephemeral, and localism has fragmented power into tribal or smaller regional units. These trends have continued to the present day in Iraq. The prehistory of the Ancient Near East begins in the Lower Paleolithic period. Therein, writing emerged with a pictographic script, Proto-cuneiform , in the Uruk IV period ( c. late 4th millennium BC ). The documented record of actual historical events—and
13320-622: The work done is defined as W = F ⋅ x {\displaystyle W=\mathbf {F} \cdot \mathbf {x} } . In this case, power can be written as: P = d W d t = d d t ( F ⋅ x ) = F ⋅ d x d t = F ⋅ v . {\displaystyle P={\frac {dW}{dt}}={\frac {d}{dt}}\left(\mathbf {F} \cdot \mathbf {x} \right)=\mathbf {F} \cdot {\frac {d\mathbf {x} }{dt}}=\mathbf {F} \cdot \mathbf {v} .} If instead
13440-778: The world's most ancient highly developed, and socially complex states. The region was one of the four riverine civilizations where writing was invented, along with the Nile valley in Ancient Egypt , the Indus Valley civilization in the Indian subcontinent , and the Yellow River in Ancient China . Mesopotamia housed historically important cities such as Uruk , Nippur , Nineveh , Assur and Babylon , as well as major territorial states such as
13560-670: Was a steam jack driven by a steam turbine , described in 1551 by Taqi ad-Din Muhammad ibn Ma'ruf in Ottoman Egypt . The cotton gin was invented in India by the 6th century AD, and the spinning wheel was invented in the Islamic world by the early 11th century, both of which were fundamental to the growth of the cotton industry . The spinning wheel was also a precursor to the spinning jenny . The earliest programmable machines were developed in
13680-430: Was an important contribution to astronomy and the philosophy of science and some scholars have thus referred to this new approach as the first scientific revolution. This new approach to astronomy was adopted and further developed in Greek and Hellenistic astronomy. In Seleucid and Parthian times, the astronomical reports were thoroughly scientific. How much earlier their advanced knowledge and methods were developed
13800-612: Was applied to milling grain, and powering lumber, machining and textile operations . Modern water turbines use water flowing through a dam to drive an electric generator . Windmill: Early windmills captured wind power to generate rotary motion for milling operations. Modern wind turbines also drives a generator. This electricity in turn is used to drive motors forming the actuators of mechanical systems. Engine: The word engine derives from "ingenuity" and originally referred to contrivances that may or may not be physical devices. A steam engine uses heat to boil water contained in
13920-497: Was converted to a time-mile used for measuring the travel of the Sun, therefore, representing time. The roots of algebra can be traced to the ancient Babylonia who developed an advanced arithmetical system with which they were able to do calculations in an algorithmic fashion. The Babylonian clay tablet YBC 7289 ( c. 1800 –1600 BC) gives an approximation of √ 2 in four sexagesimal figures, 1 24 51 10 , which
14040-412: Was instrumental in early map-making . The Babylonians also had theorems on how to measure the area of several shapes and solids. They measured the circumference of a circle as three times the diameter and the area as one-twelfth the square of the circumference, which would be correct if π were fixed at 3. The volume of a cylinder was taken as the product of the area of the base and the height; however,
14160-618: Was more generally applied to all the lands between the Euphrates and the Tigris , thereby incorporating not only parts of Syria but also almost all of Iraq and southeastern Turkey . The neighbouring steppes to the west of the Euphrates and the western part of the Zagros Mountains are also often included under the wider term Mesopotamia . A further distinction is usually made between Northern or Upper Mesopotamia and Southern or Lower Mesopotamia . Upper Mesopotamia, also known as
14280-458: Was the inclined plane (ramp), which has been used since prehistoric times to move heavy objects. The other four simple machines were invented in the ancient Near East . The wheel , along with the wheel and axle mechanism, was invented in Mesopotamia (modern Iraq) during the 5th millennium BC. The lever mechanism first appeared around 5,000 years ago in the Near East , where it was used in
14400-450: Was the first recorded. Mesopotamians believed that the world was a flat disc, surrounded by a huge, holed space, and above that, heaven . They believed that water was everywhere, the top, bottom and sides, and that the universe was born from this enormous sea. Mesopotamian religion was polytheistic . Although the beliefs described above were held in common among Mesopotamians, there were regional variations. The Sumerian word for universe
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