A water main of 1 m in diameter and 25 mm thick is subjected to an internal pressure of 2.5 N/mm2. Calculate the longitudinal stress induced.

A water main of 1 m in diameter and 25 mm thick is subjected to an int

1.	A water main of 1 m in diameter and 25 mm thick is subjected to an internal pressure of 2.5 N/mm2. Calculate the longitudinal stress induced.
A.	20 N/mm2
B.	25 N/mm2
C.	30 N/mm2
D.	35 N/mm2
Answer» C.