>>14139765At exactly the hole, you can calculate the pressure by simply analyzing the total weight divided by the area. Since the two weights here scale equally with area, the two columns ought to have the same ratio, and hence pressure, when they reach the final tub with the object.
Now here's where things get interesting. Since we know the pressure at this point pushing up, we have to then realize that pressure at the same levels cannot be different or else we would induce flow. We likewise also have to conclude that the pressure increases as we go down proportional to the extra weight added, and hence linearly with depth. These two facts are in the steady state, but not the transitory state so let's now consider opening an ideal hatch.
At that moment, the force at the entrance from above would be significantly more than the force from below. However, as the water is incompressible and has no where to go, it either blows up the container or immediately gets into rigid equal and opposite force with the column. What is truly unintuitive about this is just the fact that water is incompressible.
