Oleg Zabluda's blog
Thursday, November 08, 2012

Brief history of science friction.

Brief history of science friction.

In our high school physics lab, taught by Anatoly Muchnik [1], a major piece of measuring equipment was, what he called a "tribometer". It was a 1 meter long section of 2x4 wooden plank, used to study friction. We could either make an incline plane out of it, then coefficient of friction is equal to the tangent of the angle, or we could drag stuff on its surface with a small handheld spring scales, which we called "dynamometer".

I was pretty sure he was puling our leg, when he called the piece of wood a "tribometer". Turns out he didn't.

The whole field of study is called "tribology" from Gk "tribos" (rubbing), with its own history, magazines, etc.

Leonardo da Vinci (1452–1519) was the first to enunciate two laws of friction (independence in contact area and linear dependence on normal force), but his findings remained unpublished in his notebooks.

These classic rules were rediscovered in 1699 by a French scientific instrument inventor and physicist Guillaume Amontons (1663-1705). First law was met with much skepticism at the time, because "clearly" friction must depend on the area of contact.

It was independently verified only in 1781 by French physicist Charles-Augustin de Coulomb (1736-1806). also known for Coulomb's law, and the unit of electric charge.

Physical explanation for these laws of friction were given in 1950 by Australian physicist Frank Philip Bowden (1903-1968), and British physicist David Tabor (1913-2005), who coined term "tribology", and was the first recipient of the Gold Medal of Tribology from the Institution of Engineers, 1972. There is no "lifting over roughness involved", only Van der Waals adhesion.

Friction also propels the cart directly downwind faster than the wind: