Editing Simple machine (section)

==History==
[[File:Archimedes lever.png|thumb|upright=1.4|Engraving from an 1824 mechanics magazine illustrating Archimedes's statement that given a place to stand, with a lever a person could move the Earth]] 
The idea of a simple machine originated with the Greek philosopher [[Archimedes]] around the 3rd century BC, who studied the [[Aristotelian physics|Archimedean]] simple machines: lever, pulley, and [[Screw (simple machine)|screw]].<ref name="Asimov1988"/><ref name="Chiu">{{Citation
  | last = Chiu
  | first = Y. C.
  | title = An introduction to the History of Project Management
  | publisher = Eburon Academic Publishers
  | year = 2010
  | location = Delft
  | pages = 42
  | url = https://books.google.com/books?id=osNrPO3ivZoC&q=%22heron+of+alexandria%22++load+motion&pg=PA42
  | isbn = 978-90-5972-437-2}}</ref> He discovered the principle of [[mechanical advantage]] in the lever.<ref>{{cite book
  |last1=Ostdiek
  |first1=Vern
  |last2=Bord
  |first2=Donald
  |title=Inquiry into Physics
  |year=2005
  |publisher=Thompson Brooks/Cole
  |isbn=978-0-534-49168-0
  |url=https://books.google.com/books?id=7kz2pd14hPUC&pg=PA123
  |access-date=2008-05-22
  |page=123}}</ref> Archimedes' famous remark with regard to the lever: "Give me a place to stand on, and I will move the Earth," ({{langx|el|δῶς μοι πᾶ στῶ καὶ τὰν γᾶν κινάσω}})<ref>Quoted by [[Pappus of Alexandria]] in ''Synagoge'', Book VIII</ref><ref name="Dupac">{{cite book
  | last1 = Dupac
  | first1 = Mihai
  | last2  = Marghitu
  | first2 = Dan B.
  | title = Engineering Applications: Analytical and Numerical Calculation with MATLAB
  | publisher = John Wiley and Sons
  | series = 
  | volume = 
  | edition = 
  | date = 2021
  | location = 
  | pages = 295
  | language = 
  | url = https://books.google.com/books?id=13whEAAAQBAJ&pg=PA295
  | archive-url= 
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  | doi = 
  | id = 
  | isbn = 9781119093633
  | mr = 
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  | jfm =}}</ref><ref name="Dijksterhuis">{{cite book
  | last = Dijksterhuis
  | first = Eduard Jan 
  | title = Archimedes
  | publisher = Princeton University Press
  | date = 2014
  | location = 
  | pages = 15
  | language = 
  | url = https://books.google.com/books?id=Vvj_AwAAQBAJ&q=Archimedes+%22Give+me+a+place+to+stand+on,+and+I+will+move+the+Earth%22
  | archive-url= 
  | archive-date=
  | doi = 
  | id = 
  | isbn = 9781400858613
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  | jfm =}}</ref> expresses his realization that there was no limit to the amount of force amplification that could be achieved by using mechanical advantage. Later Greek philosophers defined the classic five simple machines (excluding the [[inclined plane]]) and were able to calculate their (ideal) mechanical advantage.<ref name="Usher"/> For example, [[Heron of Alexandria]] ({{circa|10}}–75 AD) in his work ''Mechanics'' lists five mechanisms that can "set a load in motion": [[lever]], [[windlass]], [[pulley]], [[wedge (mechanical device)|wedge]], and [[screw]],<ref name="Chiu" /> and describes their fabrication and uses.<ref>{{cite conference
  | first = Viktor
  | last = Strizhak
  |author2=Igor Penkov |author3=Toivo Pappel
   | title = Evolution of design, use, and strength calculations of screw threads and threaded joints
  | book-title = HMM2004 International Symposium on History of Machines and Mechanisms
  | publisher = Kluwer Academic
  | year = 2004
  | url = https://books.google.com/books?id=FqZvlMnjqY0C&q=%22archimedean+simple+machine%22
  | isbn = 1-4020-2203-4
  | access-date = 2008-05-21
  |page=245}}</ref> However the Greeks' understanding was limited to the [[statics]] of simple machines (the balance of forces), and did not include [[Dynamics (mechanics)|dynamics]], the tradeoff between force and distance, or the concept of [[Work (physics)|work]].

During the [[Renaissance]] the dynamics of the ''mechanical powers'', as the simple machines were called, began to be studied from the standpoint of how far they could lift a load, in addition to the force they could apply, leading eventually to the new concept of mechanical work. In 1586 Flemish engineer [[Simon Stevin]] derived 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 {{lang|it|Le Meccaniche}} (''On Mechanics''), in which he showed the underlying mathematical similarity of the machines as force amplifiers.<ref name="Krebs">{{cite book
  |last=Krebs
  |first=Robert E.
  |title=Groundbreaking Experiments, Inventions, and Discoveries of the Middle Ages
  |year=2004
  |publisher=Greenwood
  |isbn=978-0-313-32433-8
  |url=https://books.google.com/books?id=MTXdplfiz-cC&q=%22mechanics+Galileo+analyzed%22&pg=PA163
  |access-date=2008-05-21
  |page=163}}</ref><ref name="Stephen">{{cite book
  | last = Stephen
  | first = Donald
  |author2=Lowell Cardwell
  | title = Wheels, clocks, and rockets: a history of technology
  | publisher = W. W. Norton & Company
  | year = 2001
  | location = US
  | pages = 85–87
  | url = https://books.google.com/books?id=BSfpFLV1nkAC&q=%22simple+machine%22+galileo&pg=PA86
  | isbn = 978-0-393-32175-3}}</ref> He was the first to explain that simple machines do not create [[energy]], only transform it.<ref name="Krebs" />

The classic rules of sliding [[friction]] in machines were discovered by [[Leonardo da Vinci]] (1452–1519), but were unpublished and merely documented in his notebooks, and were based on pre-Newtonian science such as believing friction was an [[Aether (classical element)|ethereal]] fluid. They were rediscovered by [[Guillaume Amontons]] (1699) and were further developed by [[Charles-Augustin de Coulomb]] (1785).<ref>{{cite book
  | last = Armstrong-Hélouvry
  | first = Brian
  | title = Control of machines with friction
  | publisher = Springer
  | year = 1991
  | pages = 10
  | url = https://books.google.com/books?id=0zk_zI3xACgC&q=friction+leonardo+da+vinci+amontons+coulomb&pg=PA10
  | isbn = 978-0-7923-9133-3}}</ref>
<!-- I am commenting this section out because the references are not substantial and there is no question about what the Renaissance scientists considered to be simple machines. I think this section is confusing to readers.
==Alternate definitions==
Any list of simple machines is somewhat arbitrary; the central idea is that every mechanism that manipulates force should be able to be understood as a combination of devices on the list.  Some variations that have been proposed to the classical list of six simple machines:
* Some exclude the wedge from the list of simple machines, as it is a moving inclined plane.<ref name="Asimov1988"/>
* The screw, being a [[helical]] inclined plane,<ref>{{cite web|url=http://cnx.org/content/m13594/latest/|title=Simple Machine Elements|website=cnx.org}}</ref> is sometimes also excluded.<ref>{{cite book
  |last=Carhart
  |first=Henry S.
  |last2=Chute
  |first2=Horatio N.
  |title=Physics with Applications
  |year=1917
  |publisher=Allyn & Bacom
  |pages=[https://archive.org/details/physicswithappl00chutgoog/page/n188 159]–60
  |url=https://archive.org/details/physicswithappl00chutgoog
  |access-date=2008-05-20}}</ref> This position is less accepted because a screw converts a rotational force ([[torque]]) to a linear force.
* It has been said that the pulley and the wheel and axle can be viewed as unique forms of levers, leaving only the lever and the inclined plane as simple machines from which all others can be derived.<ref>{{cite web
  |last=Isbell
  |first=Pam
  |title=Simple machines, or are they?
  |year=2001
  |work=Grade 5–7 lesson plan
  |publisher=2001 National Teacher Training Institute
  |url=http://www.myetv.org/education/ntti/lessons/2001_lessons/simplemachines.cfm
  |access-date=2008-05-13}}</ref><ref name="Clute">{{cite book
  |last=Clute
  |first=Willard N.
  |title=Experimental General Science
  |year=1917
  |publisher=P. Blakiston's Son & Co.
  |location=Philadelphia, Pennsylvania
  |pages=[https://archive.org/details/experimentalgen00clutgoog/page/n208 188]
  |url=https://archive.org/details/experimentalgen00clutgoog
  |access-date=2008-05-20}}</ref><ref name="BNET">{{cite web
  |title=Mechanical Advantage and Simple Machines
  |year=2002
  |work=BNET Business Network
  |publisher=CNET
  |url=http://findarticles.com/p/articles/mi_gx5226/is_2002/ai_n19143765/pg_1
  |access-date=2008-05-21}}</ref><ref name="Beiser">{{cite book
  |last=Beiser
  |first=Arthur
  |year=2004
  |title=Schaum's Outline of Applied Physics
  |publisher=McGraw-Hill
  |url=https://books.google.com/books?id=soKguvJDgmsC&dq=Hydraulic+%22simple+machines%22&cad=0
  |isbn=0-07-142611-6
  |access-date=2008-05-21
  |page=145}}</ref>
* [[Hydraulic]] systems can also provide amplification of force, so some say they should be added to the list.<ref name="BNET"/><ref>This was first suggested by [[Blaise Pascal]] in the 17th century: {{cite book
  |last=Meli
  |first=Domenico Bertolini
  |title=Thinking with Objects:The Transformation of Mechanics in the 17th Century
  |year=2006
  |publisher=JHU Press
  |isbn=0-8018-8427-6
  |url=https://books.google.com/books?id=qbS_0qAB3_cC&dq=Hydraulic+%22simple+machines%22&cad=0|page=175}}</ref><ref>{{cite web
  |title=Mechanical Advantage – Simple Machines
  |work=MCAT Exam preparation
  |date=January 7, 2008
  |publisher=Eduturca
  |url=http://www.eduturca.com/mcat-exam/mechanical-advantage-simple-machines-mcat.html
  |access-date=2008-05-21}}</ref>
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