This page provides links to pages describing two similar apparatuses we have developed at the University of Rochester to demonstrate the basic phenomenology of electrostatic shielding and electric field collapse. The shared advantage of these instruments is their convenience: they are highly portable, not in the least fragile, and very easy to use. To employ them most effectively before an audience in a classroom or lecture hall, the TESV instrument, mounted on a short camera tripod, is needed. In addition, a small, table-top model ionized air blower comes in handy for the purpose of discharging and neutralizing the PVC pipe between experiments.
Electrostatic shielding apparatus -- demonstrates the commonest measure employed to reduce the nuisances and hazards associated with triboelectric charging of powders and granular solids and flow electrification of liquids in chemical processing plants.
Electrostatic field collapse apparatus -- demonstrates some subtle effects that electrical conductors have on electric fields induced by a charged insulating object. Electrostatic field collapse, though not as well-recognized as shielding, is important nevertheless because it masks the presence of potentially hazardous electrostatic charge.
The pieces of apparatus described in the two pages linked above were developed with considerable inspiration from a new type of electrophorus originally invented by S. Kamachi of the Technical Institute of Industrial Safety in Tokyo, Japan.
S. Kamachi, "Introduction of educational implements for the prevention of hazards caused by ESD," Proceedings of ESA 1995 Annual Meeting, Laplacian Press, Morgan Hill, CA, 1995, pp. 15-21.