Directly View Electric Field Patterns
Much in the same way magnetic fields are demonstrated with iron fillings, this apparatus allows electric fields to be viewed. For use on a desktop or overhead projector, a plastic dish and base features terminals with a thumbscrew system, which permits fine height adjustment of the electrodes. Six electrodes are supplied — two point source, two line source, and two circular rings. The dish is filled to a depth of 6 - 8 mm with liquid paraffin, or other non-conducting fluid (these are not included). A small amount of semolina (not include) is sprinkled evenly on the surface of the liquid. When the terminals are connected to the power supply field patterns are formed in the semolina.