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Air friction, or air drag, is an example of fluid friction. Unlike the standard model of surface friction, such friction forces are velocity dependent. The velocity dependence may be very complicated, and only special cases can be treated analytically.
Aerodynamic drag, sometimes called wind resistance, is an effect which a vehicle must overcome more and more as speed increases. Drag is a form of friction, though some of the air's effect on the vehicle is due to a low pressure zone behind the vehicle, and a high pressure zone in front.
The air pressure would be causing drag if it were placed against the face of the object, friction would be acting along its sides, and potentially a relatively negative pressure would be acting on its back or suction.
Friction caused by air is called air resistance or drag. Bikes, cars and other moving objects experience air resistance as they move through the air.
4 Μαρ 2017 · This very short discussion attempts to describe the origins of lift and drag due to the pressure distribution over the vehicle. However, one must remember that in a very thin layer (called the boundary layer—shown by δ) near the vehicle surface there is a so-called “skin friction” which also adds to the drag coefficient (but its ...
Part of the friction is due to adhesive forces between the surface molecules of the two objects, which explains the dependence of friction on the nature of the substances. For example, rubber-soled shoes slip less than those with leather soles.
One of the simpler characteristics of friction is that it is parallel to the contact surface between surfaces and always in a direction that opposes motion or attempted motion of the systems relative to each other. If two surfaces are in contact and moving relative to one another, then the friction between them is called kinetic friction. For ...
