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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.
1 Οκτ 2024 · Friction is a force that works in opposition to the motion of an object. Frictional forces slow down the motion of the object. When friction occurs, energy is transferred by heating. Friction causes an increase in temperature of the object and its surroundings.
7 Φεβ 2015 · Air friction is the main loss which is quadratic with speed. When you have two parameters, one of them linear and one quadratic, the quadratic one eventually dominates. And it's a funny consequence of the optimisation equations that the crossover point occurs when the two losses are equal.
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. [2] [3] Types of friction include dry, fluid, lubricated, skin, and internal -- an incomplete list. The study of the processes involved is called tribology, and has a history of more than 2000 years. [4]
These characteristics not only explain some of the simpler aspects of friction—they also hold the potential for the development of nearly friction-free environments that could save hundreds of billions of dollars in energy which is currently being converted (unnecessarily) to heat.
These characteristics not only explain some of the simpler aspects of friction—they also hold the potential for the development of nearly friction-free environments that could save hundreds of billions of dollars in energy which is currently being converted (unnecessarily) into heat.
Friction causes the loss of some useful energy. In the discussions to follow, we will use the approximation that transformations are frictionless. Now, let’s look at the roller coaster in Figure 9.6. Work was done on the roller coaster to get it to the top of the first rise; at this point, the roller coaster has gravitational potential energy.
