Liquid water is a very complicated molecular liquid. It is all do to its molecular structure and the way it is shaped when it is in chemical form. When it is defined like this, you can see that it was a tetrahedral symmetry one the molecule.
Then, when it is bonding with multiple water molecules, the so called now water molecule remains water and the symmetry remains the same.
Then, when it is bonding with multiple water molecules, the so called now water molecule remains water and the symmetry remains the same.
Before I get to one a famous experiment in relation to waves, I will define some main basic ideas beforehand. The diagram on the side shows the vertical wave depth vs the travel direction. This behavior is very much like a F(x)=sin(x) graph, or F(x)=cos(x) it is a very symmetrical pattern that is created.
The cycloid here is a more explicit way of thinking of the idea.
Here I am only defining how the Sine and Cosine graphs come about. It is a circle where the upper half is defined and the lower half is also defined.
This is a very important experiment in physics, that still has scientist puzzled as to why waves behaves this way. The original experiment was conducted by Thomas Young in the late 17th century.