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Friction is the enemy of a rolling object, but it is what allows it to roll.

An object is slowed by friction between it and the surface on which it slides or rolls, as microscopic bumps and ridges on each catch on to those of the other. The greater the friction, the more a wheel’s efficiency is reduced and the more heat is produced. The lesser the friction, the more freely and efficiently the wheel rolls. This suggests that a state of zero friction would allow a wheel to roll with perfect efficiency. But the wheel would not roll at all, because of an absence of traction; instead, it would slide.

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