# Stable or Unstable or What???

Classical Mechanics Level 3

A thin walled cylindrical glass tube , filled with air has its ends spanned by soap films. The soap films are spherical and have equal radii of curvatures. By some arrangements, the soap film at both the ends are given shapes as shown ( 4 shapes).Find the number of stable configurations out of these 4. Hint : you may need volume of a dome $$V=\frac{\pi h^{2}(3R-h)}{3}$$ where V is the volume of the spherical cap of height h cut off from a sphere of radius R

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