Pál Joints
Pál Joints
This Demonstration shows a method called Pál joints that lets you move a segment to a parallel segment through an area approaching 0. If the height is , then the area swept out by the segment is . Therefore, given two parallel lines, a unit line segment can be moved continuously from one to the other sweeping out a set of arbitrarily small measure.
h
arctan(1/(h+1))≈1/(h+1)