Static Friction Coefficients

The friction coefficients considered below are for static friction cases where two solid surfaces in contact with each other are resisting relative lateral motion. It should be noted that there can be significant differences between static friction (typically higher) and kinetic (sliding) friction.

Amontons's Laws of Dry Friction

• First Law: The force of friction is directly proportional to the applied load.
• Second Law: The force of friction is independent of the apparent area of contact.
• Third Law: Kinetic friction is independent of the sliding velocity.

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