dvandom

In the recent issue of The Physics Teacher there's some photographs (subscription required) that puzzled the person who sent them in, a set of wavy skidmarks on a back road. Neatly sinusoidal, ending in a donut.

Naturally, I recognized it as the result of someone practicing their drifting, and have let both the submitter and the journal editors know. :)

( Rehosted the pics behind cut )