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Leonardo da Vinci is usually credited with conducting the first systematic study of friction in the late 15th century, a subfield now known as tribology that deals with the dynamics of interacting surfaces in relative motion. Da Vinci's notebooks depict how he pulled rows of blocks using weights and pulleys, an approach that is still used in frictional studies today, as well as examining the friction produced in screw threads, wheels, and axles. The authors of this latest paper used an experimental setup similar to da Vinci's.
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Медведев вышел в финал турнира в Дубае17:59
Как отмечается, авиакатастрофа произошла в городе Эль-Альто недалеко от местного аэропорта. В результате ЧП из салона вывалились сотни тысяч купюр боливиано (местная валюта). Очевидцы бросились собирать деньги с земли.
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Rolling out this week, WIRED’s journalistic commissions on technological decommissions—from broken-down electric cars to falling-down space stations.
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