Friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction:When surfaces in contact move...
Friction - Wikipedia
How to Make Fire by Rubbing Sticks
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Vanishing Friction
A new technique tunes friction between two surfaces, to the point where friction can vanish. MIT researchers developed a frictional interface at the atomic level. The blue corrugated surface represent...
Normal force
In mechanics, the normal force is the component, perpendicular to the surface (surface being a plane) of contact, of the contact force exerted on an object by, for example, the surface of a floor or ...
Normal force - Wikipedia
Viscosity
The viscosity of a fluid is a measure of its resistance to gradual deformation by shear stress or tensile stress. For liquids, it corresponds to the informal concept of "thickness". For example, hone...
Viscosity - Wikipedia
Lubrication
Lubrication is the process or technique employed to reduce friction between, and wear of one or both, surfaces in close proximity and moving relative to each other, by interposing a substance called a...
Parasitic drag
Parasitic drag is drag that results when an object is moved through a fluid medium (in the case of aerodynamic drag, a gaseous medium, more specifically, the atmosphere). Parasitic drag is a combinati...
Plastic deformation of solids
In physics and materials science, plasticity describes the deformation of a material undergoing non-reversible changes of shape in response to applied forces. For example, a solid piece of metal ...
Deformation (engineering)
In materials science, deformation refers to any changes in the shape or size of an object due to- The first case can be a result of tensile (pulling) forces, compressive (pushing) forces, shear, bendi...
Deformation (engineering) - Wikipedia
Rolling resistance
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 on a surface. It is mainly caused by non-ela...
Rolling resistance - Wikipedia
Belt friction
Belt friction is a term describing the friction forces between a belt and a surface, such as a belt wrapped around a bollard. When one end of the belt is being pulled only part of this force is transm...
Tribology
Tribology is the science and engineering of interacting surfaces in relative motion. It includes the study and application of the principles of friction, lubrication and wear. Tribology is a branch o...
Tribology - Wikipedia
Yield (engineering)
A yield strength or yield point of a material is defined in engineering and materials science as the stress at which a material begins to deform plastically. Prior to the yield point the material will...
Yield (engineering) - Wikipedia
Transient friction loading
Transient friction loading, also known as TFL, is the mechanical stress induced on an object due to transient or vibrational frictional forces.
A classic example of TFL is the wooden block sliding...
Bingham plastic
A Bingham plastic is a viscoplastic material that behaves as a rigid body at low stresses but flows as a viscous fluid at high stress. It is named after Eugene C. Bingham who proposed its mathematical...
Bingham plastic - Wikipedia
Boundary friction
Boundary friction occurs when a surface is at least partially wet, but not so lubricated that there is no direct friction between two surfaces.
When two consistent, unlubricated surfaces slide aga...
Brinelling
Brinelling /ˈbrɪnəlɪŋ/ is the permanent indentation of a hard surface. It is named after the Brinell scale of hardness, in which a small ball is pushed against a hard surface at a preset level of forc...
Dashpot
A dashpot is a mechanical device, a damper which resists motion via viscous friction. The resulting force is proportional to the velocity, but acts in the opposite direction, slowing the motion and ab...
Dashpot - Wikipedia
Gear
A gear or cogwheel is a rotating machine part having cut teeth, or cogs, which mesh with another toothed part to transmit torque, in most cases with teeth on the one gear being of identical shape, and...
Gear - Wikipedia
Friction idiophones
Friction idiophones is designation 13 in the Hornbostel-Sachs system of musical instrument classification. These idiophones produce sound by being rubbed either against each other or by means of a non...
Fire-saw
A fire-saw is a primitive tool to create fire. It is typically an object "sawed" against a piece of wood, using friction to create an ember. It is divided into two components: a "saw" and a "hearth" (...
Fire-saw - Wikipedia
List of tribology organizations
This is a list of organizations involved in research in or advocacy of tribology, the scientific and engineering discipline related to friction, lubrication and wear.
List of tribology organizations - Wikipedia
Bearing (mechanical)
A bearing is a machine element that constrains relative motion to only the desired motion, and reduces friction between moving parts . The design of the bearing may, for example, provide for free line...
Bearing (mechanical) - Wikipedia
Strain gauge
A strain gauge is a device used to measure strain on an object. Invented by Edward E. Simmons and Arthur C. Ruge in 1938, the most common type of strain gauge consists of an insulating flexible backi...
Strain gauge - Wikipedia
Bow drill
The bow drill is an ancient form of drilling tool. It commonly was used to make fire and in this function it also was called a fire drill. However, the same principle also was used widely in drilling ...
Drucker-Prager yield criterion
The Drucker–Prager yield criterion is a pressure-dependent model for determining whether a material has failed or undergone plastic yielding. The criterion was introduced to deal with the plastic def...
Drucker-Prager yield criterion - Wikipedia
Tesla turbine
The Tesla turbine is a bladeless centripetal flow turbine patented by Nikola Tesla in 1913. It is referred to as a bladeless turbine. The Tesla turbine is also known as the boundary layer turbine, c...
Tesla turbine - Wikipedia