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by TylerE 2505 days ago
If there was zero slippage there would be zero acceleration.
3 comments

My understanding is that tires, even when accelerating, can operate in the static coefficient of friction range. And, you want them to operate in the range, because it provides the greatest acceleration. But, maybe my mental model is wrong. The following video is from someone who has considered it much more in depth.

https://youtu.be/iyeLXkacocA

That is a "driver's view" of tire slip (for best results, don't spin or slide the tires too much) rather than a chassis or tire engineer's view of tire slip (if you don't slip the tires, you can't generate any force).
Not quite right? The tires have strain, but they do not have to slip on the surface.
That's not very intuitive. Can you provide a longer explanation for this?
Here's a pretty decent, graspable explanation: https://physics.stackexchange.com/questions/142463/does-a-ti...

Tires that are not slipping are not creating any force against the road surface (so they don't have to slip when coasting, but will slip while accelerating longitudinally [braking or accelerating fore/aft] or laterally [cornering]).

Would you say that a rubber belt on a pulley is slipping? I’m sure at a microscopic level there are some places where the belt isn’t making perfect contact and the rubber is slipping across the pulley, but at a macro level, the belt remains in contact with the pulley in the same place from when it initially contacts until it disconnects.
https://youtu.be/ZVW9uMeFXK8

Yet another video about static coefficient of friction on tires that aren’t slipping. Electric cars are more easily able to keep their tires in this maximum static coefficient of friction range, maximizing acceleration.

At a micro level, I would say that a rubber V-belt on a pulley which is transferring significant force is slipping as an unavoidable element of delivering that force.

What traction control/ABS does is keep the the tire slip ratio in the right range to optimize acceleration. https://www.researchgate.net/figure/Typical-tire-longitudina...

What we intuit about whether or not we're slipping our tires every time we brake for and then drive away from a traffic light "without slipping them" is not actually correct at a micro level. With respect to this thread, it is the micro level that is relevant to tire wear and resulting particulate emissions from that slippage.