Consider a bicycle first. Pedaling the bicycle merely rotates the back wheel in clockwise sense. The velocity of point of contact is therefore backwards. Hence, friction must act forward on the rear wheel.
This frictional force causes a translational acceleration of the entire bicycle, including the front wheel. The velocity of point of contact tends to develop in the forward direction. So friction acts in the backward direction.
Similar reasoning apply to a car, for the engine merely rotates the backwheel
Moderation Team
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