Same absolute speed
This activity belongs to the GeoGebra book Attractive projects.
As a consequence of the above, if you want the animation of two points in different paths to run at the same "absolute" speed, you must calculate the length of each path and divide the speed of the animated point with it.
In the case that a path has infinite length (like a line or a parabola), we must place the animated point in a part of it (segment or arc) of finite length.
Author of the construction of GeoGebra: Rafael Losada