A thin cylindrical pressure vessel with closed-ends is subjected to internal pressure. The ratio of circumferential (hoop) stress to the longitudinal stress is

A cylindrical tank with closed ends is filled with compressed air at a pressure of $$500 kP$$a. The inner radius of the tank is $$2 m,$$ and it has wall thickness of $$10 mm.$$ The magnitude of maximum in-plane shear stress (in $$MP$$a) is ________

A gas is stored in a cylindrical tank of inner radius $$7$$ m and wall thickness $$50$$ mm. The gage pressure of the gas is $$2$$ MPa. The maximum shear stress (in MPa) in the wall is

A long thin walled cylindrical shell, closed at both the ends, is subjected to an internal pressure. The ratio of the hoop stress (circumferential stress) to longitudinal stress developed in the shell is