Coefficient of Friction Question

AI Thread Summary
The discussion centers on the relationship between static, kinetic, and rolling friction. It is clarified that static friction acts when an object is at rest, while kinetic friction applies when the object is in motion but slowing down due to friction. The question posed is whether the coefficients should follow the order of rolling friction being less than kinetic, which in turn is less than static friction. Participants confirm that typically, static friction is greater than kinetic friction, and rolling friction is usually the least. Understanding these relationships is crucial for analyzing motion and frictional forces effectively.
JWest
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What is the relationship between static, kinetic, and rolling? Is static supposed to be less than kinetic and kinetic less than rolling? Can someone help me out?
 
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If there's no friction, an object can't roll.

Static friction occurs when the object stops moving, i.e. when the force provided by friction cancels out the net-force.

Kinetic friction occurs when the object continues moving with decreasing acceleration due to friction until it eventually comes to rest.
 
What I'm asking is should the static coefficient of friction always be less than the kinetic and the kinetic always be less than rolling?
 
rolling < kinetic < static
 
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