Understanding Coefficient of Friction: Answers to Common Questions

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The coefficient of friction (COF) can exceed one, indicating that the frictional force is greater than the normal force, though this is not common. The kinetic friction coefficient is typically lower than the static friction coefficient due to the temporary bonding of surfaces, which becomes less effective at higher velocities. As speed increases, the frictional force diminishes because the surfaces do not have enough time to bond effectively. Understanding these principles is crucial for applications involving friction in various materials. Overall, the behavior of COF is influenced by surface interactions and velocity.
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hello everyone. Can anyone please help with following questions?

1. Can coefficient of friction (both static and dynamic) be greater than one? What happens if it is greater than 1 ?
2. Why coefficient of kinetic friction is less than coefficient of static friction and why it decreases at higher velocities?

Thanking you in advance.:smile:
 
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1. There is nothing magical about 1 for COF.
2. Friction is due to temporary welding of the two surfaces, which is less effective as speed increases.
 

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