Demonstrations

Van de Graaff generator

Code Number :	5A50.30
Disclaimer:	Reprinted by permission of Dick Berg, University of Maryland, for use on this website. The demonstrations contained and referenced herein are listed for the purposes of cataloging and describing physics demonstrations which should be conducted only under the direction of a trained instructional support professional or physicist. These demonstrations are not presented for the purpose of being conducted by persons unconnected to this Facility and/or persons not consulting with or being supervised by the recognized instructional support professional or physicist and his/her staff. The University is responsible only for those demonstrations carried out using its own equipment using established safety and scheduling policies, and bears no responsibility for those choosing to use this source material for their own purposes. All demonstrations described and contained herein are public domain, and can also be found in reference materials in libraries, bookstores, and electronic sources. Further information regarding legal liability in use of demonstrations and labs will be found on the web site Injuries in School/College Laboratories in USA. The University of Iowa Disclaimers: University of Iowa Disclaimer All Rights Reserved..
Condition :	Good
Principle :	Electrostatics
Area of Study :	Electricity & Magnetism
Equipment :	Van de Graaff generator, Charging & Discharging Rods, Bell Chimes, Rotating Disk, Lucite Stand for Disk and Chimes, Tin Pie Plates (large and small), Rice Krispies, Cheerios, Popcorn, Styrofoam Peanuts, Styrofoam Cups, Metal Cups, Paper Towel Hair, Wig, Packing Foam, Fluorescent light tube, Pith Balls, Electrostatic Pinwheel, Zeppelin Shaped Conducting Shell, Butterfly Net, Small Hollow Sphere and Half Spheres, Electrophorus Apparatus.
Procedure :	The 'hair' is prepared by cutting Kleenex or Kaydry towel. The wig may need to be combed. On several of the charging rods there are holes into which banana plug cords may be inserted. Attach the other end of the banana cord in the fitting on the bottom of the Van de Graff generator. If additional grounding is needed ground to the air pipes in the lecture rooms. New belts for our Van de Graaff generators may be obtained from Sargent-Welch. Search the Sargent-Welch website for part # WL1913B. These belts should have a flat length of 14 - 1/4 inches flat length, and be 1 - 7/8 inches wide. The bell chimes and rotating disks will work with either the Van de Graaff or the Wimshurst machine, although the Wimshurst is preferable because it does not make as much noise. Some things to put on a VdG so that they fly off: tin pie plates, Rice Krispies in a cup, popcorn in a cup, Styrofoam peanuts in a metal vs. Styrofoam cup, cheerios. Hide popped popcorn in a Styrofoam cup, pour in un-popped popcorn, turn on VdG and watch the popped popcorn fly out. Have the students hold Styrofoam peanuts in their closed hand and touch the VDG. Turn the VDG on and when they are charged have them open their hand and see the peanuts float away.

Web Sites

"Chapter 2: Electromagnetism: A simple Homemade Van de Graaff Generator." www.scitoys.com

References

M. Talmage Fraham and James Young, "Robert Jemison "Tee" Van de Graaff: From Football Fields to Electric Fields", TPT, Vol. 42, # 8, Nov. 2004, p. 463.

"Figuring Physics", TPT, Vol. 29, # 3, Mar. 1991, p. 190.

Richard E. Berg, "Van de Graaff Generators: Theory, Maintenance, and Belt Fabrication," TPT, Vol. 28, # 5, p. 281 (May 1990).

"Figuring Physics", TPT, Vol. 28, # 2, Feb. 1990, p. 113.

Robert J. Reiland, "Two Fundamental Surprises," TPT, Vol. 27, # 5, p. 326, (May 1989).

Terry Ragsdale, "Police-Made Physics Parts", TPT, Vol. 27, # 5, May 1989, p. 326.

Dennis C. Henry, "Will Lighting Erase Magnetic Tapes?", TPT, Vol. 23, # 4, Apr. 1985, p. 233 - 235.

H. H. Barschall, "Electrostatic Accelerators", TPT, Vol. 8 , # 6, Sept. 1970, p. 316.

J. Morris Blair, "The New Generation of Van de Graaff Machines", TPT, Vol. 4, # 4, April 1966, p. 149.

Ec-1: Freier and Anderson, A Demonstration Handbook for Physics.

E-160: "Van de Graaff Generator," DICK and RAE Physics Demo Notebook.

Back Scatter, "The Birth of Electrostatics", Physics Today, p. 104, Sept. 2006.

Alexander V. Gurevich and Kirill P. Zybin, "Runaway Breakdown and the Mysteries of Lightning", Physics Today, May 2005, p. 37 - 43.

Cool Threads: Selections from TAP-L 2006, "Make Your Own VdG Belt", PIRA News, Vol. 20, # 1, p. 4, 2007.

Richard E. Berg, "Making Van de Graaff Belts", PIRA Newsletter, Vol. 3, # 10, March 8, 1989, p. 3.

R.A. Ford, "Van de Graaff Generators," Homemade Lightning, p. 78 - 90.

Simon Quellen Field, "A Simple Homemade Van de Graaff Generator", Gonzo Gizmos, p. 52 - 64.

Mail Questions and Comments to: Dale Stille