How does the friction on the front and rear wheels of a car vary?

Question

Consider a Rear-Wheel Driven car. The questions refer to friction between the wheels and the road.

1.Direction of friction on the front and rear wheels when car accelerates? Is it static or kinetic?

2.Direction of friction on the front and rear wheels when car is at constant speed? Is it static or kinetic?

3. Direction of friction on the front and rear wheels when car is decelerating? Is it static or kinetic?

Also, if friction at the car’s wheels is what causes the car to accelerate, how does it resist the car’s motion at the same time?

Answer 1

For all your 3 questions the answer is the same.
It's static friction. The effect of kinetic friction ocurs when the car is doing drift.
There's no diference if is rear wheel or front wheel driven.

The direction of the friction force is oposed as the force aplied by the wheels.

• When the car acelerates the friction points to the front of the car.

• When the car decelerates the friction points to the rear of the car.

• In corneering the friction is the resultant between the aceleration/deceleration friction and the lateral force (induced from the car mass).

In the drive wheels the vector is oposite to torque applied by motor. And in the ?free wheels the vector is oposite to the inner losses between components.