This is a device is a simple method for generating a high voltage charge or static electricity. It works by dripping water through an arrangement of metal containers and loops of wire.
Water, like many molecules is in the form of a dipole. This means that it has a difference in electric charge from one end to the other. The chemical formula for water is H2O, meaning there are two Hydrogen atoms and one Oxygen atom in each molecule.
You can see from the image on the right the way that the H2+ is more on one side therefore making an uneven distribution of charge i.e. a dipole. This is what gives water all its interesting properties such as its powerful solvent abilities and its ability to stick to other materials.
This experiment works best with pure or deionised water as it is a very good electrical insulator. Tap water contains dissolved ions which become mobile allowing the water to conduct electricity.
As the streams of water droplets pass through the rings, charges are induced making the drips and ring oppositely charged. If a water droplet is made more negative it will help to make the drops on the other side more positive because of the cross connection between the collector cans and the metal loops. This process continues to cause the voltage to rise until the water drops start being deflected by the strong fields or a spark is produced.
The top containers can be made from plastic but it may work better if they are made from metal and connected to ground.