• # question_answer       A thin cylinder contains fluid at a pressure of  $500\,N/{{m}^{2}},$ the internal diameter of the shell is 0.6 m and the tensile stress in the material is to be limited to $9000\,N/{{m}^{2}}.$ The shell must have a minimum wall thickness of nearly A) 9 mm               B) 11 mm         C) 17 mm             D) 21 mm

${{\sigma }_{\theta }}=\frac{pd}{2t}$ $t=\frac{500\times 0.6}{2\times 9000}=16.66=17\,mm$