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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Columbia was unable to withstand the fiery re-entry into the Earth's atmosphere, disintegrating as the world watched on in horror.
В европейской стране бизнесмен украсил город флагами и получил огромный штрафБританского бизнесмена оштрафовали за украшение города государственными флагами