Indeed. But distance is a much more intuitive way to think about the problem than frames of reference of the rotations imo. Are revolutions the coin rotating 3

Indeed. But distance is a much more intuitive way to think about the problem than frames of reference of the rotations imo. Are revolutions the coin rotating 360 degrees or are they the complete perimeter rotating across the other coin and touch the other one exactly once. The problem is intended to be mapped onto a distance perspective and figured out that way. So it’s very much distance.