Friction on a circle

[kfcman289]

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Is there any kinetic friction working on a car that is traveling in a circle or is it only static?

 

[premed1001]

if a car is moving forward in a circle, then it is no longer static, it is now kinetic friction.
before it starts moving it would be static

 

[milski]

Normally no, there is no kinetic friction. You will have kinetic friction only if the wheels were skidding. A rolling wheel experiences only static friction since there is no slipping between the surface of the wheel and the surface on which it is rolling.

http://hyperphysics.phy-astr.gsu.edu/hbase/frict2.html

 

[DrknoSDN]

if a car is moving forward in a circle, then it is no longer static, it is now kinetic friction.
before it starts moving it would be static

Sorry premed1001, but this is completely incorrect.
Milski is right.

Kinetic friction involves 2 surfaces sliding relative to one another.

Unnecessary background information:::
Car tires only experience kinetic friction when they lose traction. That's why anti-lock brake systems (ABS) were developed... Since static friction is always greater than kinetic friction, ABS prevents the tires from sliding along the pavement, instead it repeatedly releases the breaks to allow the wheel to begin rotating again (to re-establish static friction), then re-applies the breaks. It does this over and over because the kinetic friction force is much lower than the static friction force that can be produced from ABS.

Car tires under normal (non-skidding) driving conditions always use static friction.