Engineering

Popping a champagne cork reveals propulsive dynamics

Researchers have resolved the complex gas dynamics that occur upon opening a champagne bottle (or, more generally, a bottle containing a pressurized liquid and gas) and these dynamics' interaction with the bottle's cork stopper. ...

Engineering

How cars 'waste' two thirds of their fuel

With the rise in gas prices showing no signs of abating, it seems like an appropriate time to ask ourselves: are our cars not efficient enough? Europe has decided to ban the production of new combustion engine-powered vehicles ...

Robotics

Soft robots make virtual reality gloves feel more real

Soft robots, or those made with materials like rubber, gels and cloth, have advantages over their harder, heavier counterparts, especially when it comes to tasks that require direct human interaction. Robots that could safely ...

Engineering

Laser-textured discs improve marine engine performance

A laser-textured friction disk could reduce maintenance costs and downtime for the biggest ships sailing on the oceans. Man Energy Solutions tested laser-textured friction disks on its two-stroke engines on two ships sailing ...

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Friction

Friction is the force resisting the relative lateral (tangential) motion of solid surfaces, fluid layers, or material elements in contact. It is usually subdivided into several varieties:

Friction is not a fundamental force, as it is derived from electromagnetic force between charged particles, including electrons, protons, atoms, and molecules, and so cannot be calculated from first principles, but instead must be found empirically. When contacting surfaces move relative to each other, the friction between the two surfaces converts kinetic energy into thermal energy, or heat. Contrary to earlier explanations, kinetic friction is now understood not to be caused by surface roughness but by chemical bonding between the surfaces. Surface roughness and contact area, however, do affect kinetic friction for micro- and nano-scale objects where surface area forces dominate inertial forces.

This text uses material from Wikipedia, licensed under CC BY-SA