Friction between two objects. The blue one has more friction against the sloped surface than the green one.
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Simulated blocks with fractal rough surfaces, exhibiting static frictional interactions[1]
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other.[2]
Types of friction include dry, fluid, lubricated, skin, and internal.
Friction can have dramatic consequences, as illustrated by the use of friction created by rubbing pieces of wood together to start a fire. Kinetic energy is converted to thermal energy whenever motion with friction occurs, for example when a viscous fluid is stirred. Another important consequence of many types of friction can be wear, which may lead to performance degradation or damage to components.
Friction is a non-conservative force – work done against friction is path dependent. In the presence of friction, some kinetic energy is always transformed to thermal energy, so mechanical energy is not conserved. Friction is not itself a fundamental force. Dry friction arises from a combination of inter-surface adhesion, surface roughness, surface deformation, and surface contamination. The complexity of these interactions makes the calculation of friction from first principles difficult and it is often easier to use empirical methods for analysis and the development of theory.
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Types of friction include dry, fluid, lubricated, skin, and internal. Friction can have dramatic consequences, as illustrated by the use of friction created...
Friction factor may refer to: Atkinson friction factor, a measure of the resistance to airflow of a duct Darcy friction factor, in fluid dynamics Fanning...
Friction blisters are a skin condition that may occur at sites of combined pressure and friction (such as the hands or feet), and may be enhanced by heat...
In mechanics, friction torque is the torque caused by the frictional force that occurs when two objects in contact move. Like all torques, it is a rotational...
A friction burn is a form of abrasion caused by the friction of skin rubbing against a surface. A friction burn may also be referred to as skinning, chafing...
disengaged). A dry clutch uses dry friction to transfer power from the input shaft to the output shaft, for example a friction disk pressing on a car engine's...
In fluid dynamics, the Darcy friction factor formulae are equations that allow the calculation of the Darcy friction factor, a dimensionless quantity...
Friction welding (FWR) is a solid-state welding and bonding process that generates heat through mechanical friction between workpieces in relative motion...
Science Friction may refer to Science Friction (album) by Tim Berne "Science Friction" (song), from the 1977 XTC album 3D EP Science Friction (record...
prevent its motion, most often accomplished by means of friction. Most brakes commonly use friction between two surfaces pressed together to convert the...
DJ Friction may refer to: DJ Friction (UK), British drum and bass DJ and producer DJ Friction (Germany), German hip hop DJ and producer DJ Friction (IN)...
A friction motor is a simple mechanism to propel toy cars, trucks, trains, action figures and similar toys. The motor consists of a large flywheel which...
Friction stir welding (FSW) is a solid-state joining process that uses a non-consumable tool to join two facing workpieces without melting the workpiece...
A friction drive or friction engine is a type of transmission that utilises two wheels in the transmission to transfer power from the engine to the driving...
within the upper layers of the skin, usually caused by forceful rubbing (friction), burning, freezing, chemical exposure or infection. Most blisters are...
Rolling resistance, sometimes called rolling friction or rolling drag, is the force resisting the motion when a body (such as a ball, tire, or wheel) rolls...
ABS Friction is a Canadian brake manufacturer. Headquartered in Guelph, Ontario, Canada, ABS Friction Inc. produces aftermarket brake pads for more than...
Friction drilling is a method of making holes in metal in which the material is pushed out of the way with the aid of heat from friction. The process is...
Friction tape is a type of woven cloth adhesive tape, historically made of cotton, impregnated with a rubber-based adhesive. Sticky on both sides, it is...
Les Friction is an independent music group led by Helmut Vonlichten, Nihl Finch aka Evan Frankfort, and a singer named Paint. Helmut had previously collaborated...
lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated...
A friction hitch is a kind of knot used to attach one rope to another in a way that is easily adjusted. These knots are commonly used in climbing as part...
stiff paper. One end is coated with a material that can be ignited by friction generated by striking the match against a suitable surface. Wooden matches...
In astrophysics, dynamical friction or Chandrasekhar friction, sometimes called gravitational drag, is loss of momentum and kinetic energy of moving bodies...
Skin friction drag is a type of aerodynamic or hydrodynamic drag, which is resistant force exerted on an object moving in a fluid. Skin friction drag...
The term friction loss (or frictional loss) has a number of different meanings, depending on its context. In fluid flow it is the head loss that occurs...
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