coefficient of friction

British  

noun

1. mechanical engineering the force required to move two sliding surfaces over each other, divided by the force holding them together. It is reduced once the motion has started

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coefficient of friction Scientific  

1. A measure of the amount of resistance that a surface exerts on or substances moving over it, equal to the ratio between the maximal frictional force that the surface exerts and the force pushing the object toward the surface. The coefficient of friction is not always the same for objects that are motionless and objects that are in motion; motionless objects often experience more friction than moving ones, requiring more force to put them in motion than to sustain them in motion.

2. ◆ The static coefficient of friction is the coefficient of friction that applies to objects that are motionless.

3. ◆ The kinetic or sliding coefficient of friction is the coefficient of friction that applies to objects that are in motion.

4. See also drag friction

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Example Sentences

The result, says Gilchrist, is cohesion that generates a negative angle of repose due to a negative coefficient of friction.

From Science Daily • Sep. 20, 2023

The coefficient of friction between the block and the surface is 0.20.

From Textbooks • Aug. 12, 2015

For rubber tyres on a tarmac road, the coefficient of friction is about 1.0.

From BBC • Apr. 2, 2015

The degree of “stickiness” between two surfaces is expressed mathematically as the coefficient of friction.

From Washington Post • Mar. 3, 2014

The work done is independent of the length of the journal; except as it may modify pressure, and thus the coefficient of friction.

From Friction, Lubrication and the Lubricants in Horology by Lewis, William T.