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## Main Question or Discussion Point

Ok, so assume we have a wheel on the road travelling to the left. The wheel spins CCW and also has translation to the left.

If we let the wheel roll, assuming no slip, then the translation velocity to the left will counteract the rotational velocity to the right at the bottom of the wheel, so the section of the wheel touching the ground is not displaced in that moment.

So this means that the little part of the wheel is sitting on top of that piece of ground for a little moment... and then static friction? I'm confused here because isn't static friction a reaction to an opposing force? If that piece of wheel is just sitting there, like I'm sitting in a chair, what "pushing force" is that static friction trying to oppose?

If we let the wheel roll, assuming no slip, then the translation velocity to the left will counteract the rotational velocity to the right at the bottom of the wheel, so the section of the wheel touching the ground is not displaced in that moment.

So this means that the little part of the wheel is sitting on top of that piece of ground for a little moment... and then static friction? I'm confused here because isn't static friction a reaction to an opposing force? If that piece of wheel is just sitting there, like I'm sitting in a chair, what "pushing force" is that static friction trying to oppose?