Friction Phenomenology, Detection and Measurement

The failure of a lubricant film between two solid surfaces implies contact between part or all of these surfaces. One of the consequences of such contact is overtly observable frictional behavior. Friction is a part of everyday experience, with antecedents reaching far back in time but nevertheless it is still often misunderstood, both behavioristically and fundamentally. 

Instead of starting with an a definition, we shall begin our 

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