1. The problem statement, all variables and given/known data I don't know much about physics, I'm using- F=m*a 2. Relevant equations So say we got our 2 containers with a straight passage between them (they're cylinders for the sake of the question), and the right one has double the radius. So I'm assuming there are 2 forces pushing each other (in the passage), one from the weight of the right container, and one from the left. The right one has more mass (assuming they've got equal height of water which is basically what communicating vessels say). Wouldn't it be "pushing" the water in the passage with more force? If it does, does it cause a circular motion of water on the other side? Otherwise why doesn't it rise? 3. The attempt at a solution As stated above I'm proposing the motion of water moving in a circular motion on the left container. As a side note, might be negating myself, but when I'm water pushes down other water (say in the right container, water is pressing the water under it, which is next to the passage), does it push the water to the sides? Thanks in advance. http://assets.overclock.net.s3.amazonaws.com/1/17/1721d4ed_vbattach152018.png here's a picture to help understand my question.