Maximum excess pressure inside a thin-walled steel tube of radius r and thickness `/_\r (lt lt r)`, so that the tube would not rupture would be (breaking stress of steel is `sigma_("max")`

Maximum pressure difference between inner and outer surface of a thin walled circular tube of radius r and thickness Deltar(Deltar lt lt r) so that tube won't break is (Breaking stress of the material is sigma_(0))

Maximum pressure difference between inner and outer surface of a thin walled circular tube of radius r and thickness Deltar(Deltar lt lt r) so that tube won't break is (Breaking stress of the material is sigma_(0))

Excess pressure inside a soap bubble of radius r and surface tension T is

The excess pressure inside a soap bubble of radius R is (S is the surface tension)

The excess pressure inside a soap bubble P and the radius R of the bubble are related as

The excess pressure inside a soap bubble P and the radius R of the bubble are related as

The maximum surface charge density of a uniformly charged spherical radius R and wall thickness 't', so that it will not burst apart, is