Liquid In Spinning Sphere
To show the behavior of a liquid when subjected to a centripetal force.
Rotator with sphere and colored water.
Rotate sphere slowly to achieve this effect.
When the sphere is rotated, the water leaves the bottom of the sphere and forms a band in the middle of the sphere, due to the reaction to the centripetal force.
Lecture Demonstration Information Sheet. ◙D. James Baker, Jr., Demonstrations of Fluid Flow in a Rotating System, AJP 32, 647-652 (1966).