A hyperbolic paraboloid
Can we put a straight rule inside a hole with the shape of a hyperbole? This experience shows that the hyperbolic paraboloid is a ruled surface. From the exhibition Matemática viva, Lisbon, 2000.
The image belongs to the sections...:
From the exhibition "Matemática viva", Lisbona, 2000 (Other exhibitions around the world)
Ruled surfaces (3D geometry)