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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Ранее стало известно, что Роман Каптелов не задекларировал сведения о том, что его жена и дети, проживающие в России, имеют недвижимость в Москве. Кроме того, выяснилось, что жена парламентария работает в столице РФ в организации, сотрудничающей с российским центром военно-спортивной подготовки молодежи.
The Indian state of Kerala, known as “God’s own country” for its golden beaches and lush tea plantations, is to be given a new name.
2026-02-27 00:00:00:03014245410http://paper.people.com.cn/rmrb/pc/content/202602/27/content_30142454.htmlhttp://paper.people.com.cn/rmrb/pad/content/202602/27/content_30142454.html11921 本版责编：杨 彦 孙 振 戴林峰 刘雨瑞