What is Traction (engineering)?
[[File:Traction Tires2 (5124406182).jpg|thumb|right|250px|{{Center|These tires have grooves in them for all-weather traction}}]] '''Traction''', or '''tractive force''', is the [[force]] used to generate [[Motion (physics)|motion]] between a [[Physical body|body]] and a [[surface]]. This is usually due to [[friction]], though the use of [[shear strength (soil)|shear]] force of the surface is also commonly used.<ref>Evaluating Vehicle Mobility Using Bekker's Equations, U.S. Army TARDEC, dated 2000, http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA457941{{Dead link|date=September 2021 |bot=InternetArchiveBot |fix-attempted=yes }}</ref> Traction can also mean the maximum tractive force between a body and a surface, as limited by available friction. When this is the case, traction is often expressed as the ratio of the maximum tractive force to the [[normal force]] and is termed the ''coefficient of traction'' (similar to [[coefficient of friction]]). == Motor vehicles == Traction is an important force to motor [[vehicles]]. [[Tire]]s, usually made of [[rubber]], depend on traction to move a vehicle forward.<ref>{{cite web |url=http://www.school-for-champions.com/science/friction_traction.htm#.VeN2OPlViko|title=Traction Friction of Tires|author=Ron Kurtus|date=28 March 2008|publisher=School for Champions|access-date=30 August 2015}}</ref> In [[Transmission|manual transmission]] [[car]]s and [[truck]]s, a [[clutch]] is a friction device that connects the [[engine]] to the [[drivetrain]] of the vehicle. To work properly, the clutch must have traction. == References == {{reflist}} {{transport-stub}} [[Category:Mechanical engineering]]