A thin cylinder shell of diameter (d), length (l) and thickness (l), is subjected to an internal pressure (p). The circumferential or hoop strain is
1
\(\frac{{pd}}{{2tE}}\left( {1 - 2\nu } \right)\)
2
\(\frac{{pd}}{{4tE}}\left( {1 - 2\nu } \right)\)
3
\(\frac{{pd}}{{2tE}}\left( {2 - \nu } \right)\)
4
\(\frac{{pd}}{{4tE}}\left( {2 - \nu } \right)\)