Which statement describes a critical speed scuff?

Which statement describes a critical speed scuff?

• A. It is a tire mark that is rotating
• B. It is a tire mark that is slipping only
• C. It is a tire mark that is both rotating and slipping
• D. It is a mark left by a broken tire

Answer: (C)

Understanding tire marks shows whether a tire was rotating, slipping, or both. A critical speed scuff is created when the tire is still rotating while it is sliding across the road’s surface. The combination produces a curved, smeared mark that reflects both the wheel’s rotation and the forward movement of the vehicle. If the tire were rotating without slipping, the mark would not show the sliding smear; if it were slipping without rotating, you’d get a straight skid line without the rotating pattern. A mark from a broken tire wouldn’t display this rotating-slipping signature.

Understanding tire marks shows whether a tire was rotating, slipping, or both. A critical speed scuff is created when the tire is still rotating while it is sliding across the road’s surface. The combination produces a curved, smeared mark that reflects both the wheel’s rotation and the forward movement of the vehicle. If the tire were rotating without slipping, the mark would not show the sliding smear; if it were slipping without rotating, you’d get a straight skid line without the rotating pattern. A mark from a broken tire wouldn’t display this rotating-slipping signature.