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Assuming a car is traveling on a road. At some point, the driver stops accelerating the car, so it travels some distance and then stops.

Since the car's wheels are round and are rotating without slipping, friction must not be the force that stops the car eventually. So which force is it?

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    $\begingroup$ Possible duplicates: physics.stackexchange.com/q/149409/2451 and links therein. $\endgroup$
    – Qmechanic ♦
    Oct 2, 2015 at 11:59
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    $\begingroup$ I assume in your "car" example you want us to ignore friction in the engine (considerable) and air drag, and focus just on an "ideal rolling car" and the forces in the wheels. Maybe make the bearings perfect too, so the only component left is the true "rolling resistance". Otherwise there are in fact so many factors at play... $\endgroup$
    – Floris
    Oct 2, 2015 at 12:11

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In a practical scenario,

When a sphere rolls on a surface, the sphere deforms near contact surface. The contact is therefore not at a single point ,but over an extended area. when one segment of this "area of contact" 'pushes on' the table more strongly than the other,the normal force on the sphere shifts.It lno longer passes through the centre,it is shifted towards the former segment.

This force,then has a torque in the opposite sense that tneds to cause an angular deceleration.enter image description here

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  • $\begingroup$ The earlier answer in a related question shows nicely why the normal force is displaced with respect to the center. You might expand this answer to show this. Also, you might want to clarify (and maybe move) this "f" on your diagram, and show the direction of travel. $\endgroup$
    – Floris
    Oct 2, 2015 at 12:08

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