A soap film between two rings — stretched to the breaking point
Connected — cylindrical film
h/R = 0.05
At the breaking point: V = (π/2)R²h — exactly half the cylinder. skwedge.org
Catenoid
Skwedge curvum
h=0
hcrit ≈ 1.3255R
1.8R
The catenoid — a minimal surface of revolution. At h/R = 2λ ≈ 1.3255, the film ceases to exist.
Right at the breaking point, it encloses exactly half its bounding cylinder.