고체역학 (Gere) — Applications of Plane Stress: Problem 8.2-1

8.2-1 A spherical balloon is filled with a gas. The outer diameter of the balloon is 500 mm and the thickness is 0.3 mm. Calculate the maximum permissible pressure in the balloon if the allowable tensile stress and the allowable shear stress in the balloon are 7 MPa and 2 MPa, respectively.