centripetal force ?

Question

what provides centripetal force for a car driving in a circle ?
is it traction or friction ? cause i heard both answers.

Answer 1

Static friction between the tyres and the road provides the centripetal force.

Answer 2

Yes.

Just kidding...it is both answers. Friction and traction are the same thing; they both mean how sticky one surface is over another surface. Traction is taken a bit more specific than friction because traction usually connotes a friction force in the fore-aft direction. Whereas, friction is more general and includes friction forces, if any, in any direction.

So traction is needed to get the car moving at speed v. Without traction, the car would just spin its wheels and go nowhere. And the car needs speed because v is a major factor in C = mv^2/R; where m is the car's mass and R is the radius of turn around that circle.

C is centifugal force, which pulls the car outward away from the center of the turn. And, as the car stays in the track, there is an opposing force so the net force f = ma = (P - C) = 0. The a here is the car's acceleration along the radius of turn; it's the radial acceleration.

P = kN; where P is the centripetal force that comes from friction acting along the radius direction to offset the C force. k is the static coefficient of friction between the tires and the road, N is the normal weight = mg cos(theta) and theta is the road's embankment.

And there you have it; traction is needed to get a speed v and produce a centrifugal force C to counter balance P, the centripetal force stemming from friction. But traction is a specified term given to friction action in the direction of the speed.

Without that speed there would be no centripetal force because there would be no centrifugal force. Without the embankment friction there would be no centripetal force. So, as I said earlier, "yes" is the answer.

Answer 3

first of all, traction is friction, and friction is traction.

Inertia is what actually provides centripetal force. Inertial forces are what want to pull the car off the circular path into a tree or something.

Traction makes centripetal force possible. The car would stop traveling in a circle at the moment that the traction force is exceeded by the centripetal force. This would happen due to the normal force diminishing becasue velocity increased.

Answer 4

The traction or friction of the tyres on the road are counteracting the tendency of the car to travel in a straight line (Centrifugal Force). Centripetal Force is maintaining the circular path of the car.

Answer 5

Aren't those the same thing? While the care is driving in a circle, it continues on a circle (rather than a line) because of the turn of the wheels. If you were to instantly turn the surface the car is on to a frictionless surface, the wheels would no longer grip the road, so would have no traction, and the car would slide in a line from that point.