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Since kinetic friction is lower than static friction, and a sled in motion experiences kinetic friction whereas a wheel experiences static friction, which one would go down a hill faster. Let's have a hypothetical scenario where we have a slope which both a sled and a wheel are stationed at the top of, considering all things equal, other than kinetic vs. static friction, which one would get to the bottom of the slope the fastest.

In this case the mass of the two objects is the same, the air friction is the same, they experience the same amount of gravitational pull, the surface has the same coefficient of friction for both objects, the surface stays at the same angle for both objects, and the rolling momentum of the wheel is negligible. Only rule is that the wheel rolls and the sled slides, so there is no slippage of the wheel rolling and there is also no tumbling of the sled. Intuitively I think that the sled should be faster as it experiences kinetic friction which is lower than the static friction experienced by the wheel.

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    $\begingroup$ Note that if the slope is shallow enough or if the friction coefficient is high enough, the sled won't slide down the hill at all, but it's impossible to keep the ball from rolling downhill. $\endgroup$ Commented Apr 18, 2023 at 20:19
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    $\begingroup$ "Intuitively I think that the sled should be faster as it experiences kinetic friction which is lower than the static friction experienced by the wheel" You appear to not understand the roles of kinetic vs static friction. $\endgroup$
    – Bob D
    Commented Apr 18, 2023 at 20:34

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Intuitively I think that the sled should be faster as it experiences kinetic friction which is lower than the static friction experienced by the wheel

You appear to not understand the roles of kinetic vs static friction. Static friction does not prevent or inhibit the wheel from going down hill. It enables the wheel to roll without sliding as long as the maximum possible static friction force is not exceeded. Static friction can, however, prevent the sled from sliding if the slope is too shallow. If it does slide, kinetic friction does negative work on the sled taking kinetic energy away from it.

If the sled were sliding down a frictionless slope and the wheel was rolling down the same angle slope from the same height but with static friction so that it rolls without slipping, the sled would win the race. That's simply because the translational velocity of the center of mass determines the winner and that would be higher for the sled. But that's because the kinetic energy of the sled is all translational, whereas the kinetic energy of the wheel is part translational and part rotational. It is not because the coefficient of kinetic friction is lower than the coefficient of static friction.

On the other hand, if there is kinetic friction on the slope with the sled, that friction will do negative work on the sled taking some of its translational kinetic energy away. Whether it takes enough away for it to lose the race, I leave that to you to figure out.

Hope this helps.

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