The 2-m-wide gate shown in Figure 2.68 is pinned at P and is connected to a restraining spring that keeps the gate closed until the hydrostatic force is sufficient to open it. If the gate is to open...

The 2-m-wide gate shown in Figure 2.68 is pinned at P and is connected to a restraining spring that keeps the gate closed until the hydrostatic force is sufficient to open it. If the gate is to open when the depth of water, y, is 4 m, determine the required restraining force that should be exerted by the spring.