Thanks very much for the help guys, I just want to clarify what I'm now thinking.
Is the centripetal force that makes the water go in a circle caused by the pressure gradient? Water tries to go in a straight line but can't because of the glass, so builds up around the edge and the pressure...
Rotating water forms a parabola - why??
I've done some experiments involving rotating a beaker of water, and then measuring the height of the parabola that forms. I am now trying to explain this in my write up, but there are some things that I am simply not understanding, and any help would be...