1. A closed storage tank has a cross-section consisting of a semi-circular lower part, and a rectangular upper part (see figure). The tank is filled on the left of a vertical dividing gate to the level shown (2 ft above the semi-circular part). The air above the water on the left is partially evacuated so that the (gage) pressure is negative (as shown). On the right of the gate, the water surface is at the same level where the semi-circular lower part ends and the rectangular upper begins. The vertical gate is hinged at the top, and so is free to rotate about the hinge. What is the torque to be exerted on the gate at the hinge in order to maintain the gate in its vertical position (as shown in figure)? Indicate clearly the direction, clockwise or counterclockwise), of this torque.
-0.3 psi
hinge
0.5 ft
2 ft
3 ft
2 ft
3 ft
vertical dividing gate