Calculate the hoop stress at the bottom of penstock, if a steel penstock of 1 m and 10 mm thick is subjected to 100m head of water. Take w = 9.81 kN/m3.

Calculate the hoop stress at the bottom of penstock, if a steel pensto

1.	Calculate the hoop stress at the bottom of penstock, if a steel penstock of 1 m and 10 mm thick is subjected to 100m head of water. Take w = 9.81 kN/m³.
A.	49 N/mm<sup>2</sup>
B.	47 N/mm<sup>2</sup>
C.	45 N/mm<sup>2</sup>
D.	43 N/mm<sup>2</sup>
Answer» B. 47 N/mm<sup>2</sup>