Cotton thread is made of many tiny fibers, each just 2-3 cm long, yet when spun together the fibers are capable of transmitting tension over indefinitely long distances. From a physics perspective, how threads and yarns transmit ...
If a hard-boiled egg is spun fast enough on a table, it will slowly stand upright as it continues to spin. Although the spinning egg rises due to the force of friction between the egg and the table, the full explanation involves ...
(Phys.org)—Many people are familiar with the friction enigma of two interleaved phonebooks, in which all of the pages of two phonebooks are overlapped, one by one, with the books' spines facing outward. Trying to separate ...
(Phys.org)—When nanosized pieces of graphite slide against each other, there can be virtually no friction between them. For many years, superlow friction, or "superlubricity," was known to exist only on the nanoscale. Then ...
(Phys.org)—In spite of its name, the time reversal of a wave doesn't involve sending the wave back in time, but for scientists, the process is almost as compelling. After a source generates a wave, the wave propagates through ...
(Phys.org) -- In the phenomenon of superlubricity, two solid surfaces can slide past each other with almost no friction. The effect occurs when the solid surfaces have crystalline structures and their lattices are rotated ...
(PhysOrg.com) -- The many ways in which water differs from other molecules is both a scientific curiosity and an important factor in shaping the Earth. Among water's unique properties are that it expands when it freezes, ...
For 15 years, scientists have been baffled by the mysterious way water flows through the tiny passages of carbon nanotubes—pipes with walls that can be just one atom thick. The streams have confounded all theories of fluid ...
Nanophysics
Feb 2, 2022
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A team of researchers from University of Toronto Engineering and Rice University have reported the first measurements of the ultra-low-friction behavior of a material known as magnetene. The results point the way toward strategies ...
Nanophysics
Nov 17, 2021
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The snapping of a finger was first depicted in ancient Greek art around 300 B.C. Today, that same snap initiates evil forces for the villain Thanos in Marvel's latest Avengers movie. Both media inspired a group of researchers ...
Other
Nov 16, 2021
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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
