Red shoe, black scuff?

[CuriousCitizen]

In a pedestrian accident, what color shoe scuff would be left on the road by a shoe with a bright red rubber sole? Could it be a black line? Could it be a cone-shaped "spray" of white lines? Or would it have to also be red?

[Bob Anderson]

Many plastics change color when deformed.

The best way to answer your question is to take an exemplar shoe and grind off some material to see what the material that is ground off looks like.

[WVandiver]

I agree with Bob on this and can add the following....many "marks" described as shoe scuffs involve the depositing of shoe material on the surface, and the color can vary from the original visible color of the shoe material. But, many also involve the removal or cleaning of the surface - sort of a "squeegee effect," which, on a dark surface can create the appearance of a black mark when, in fact, the roadway surface was "cleaned" or abraded by the sliding shoe. And, of course, there can be a combination of the two effects. Good luck!

[CuriousCitizen]

Would an erasure leaving a black mark still be visible the next day? And - Is there a commonly used textbook that shows what these things look like?