Demonstrations

Sunspots

Code Number :	8B10.30
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 :	Temperatures of Gas and Plasma
Area of Study :	Astronomy
Equipment :	Overhead projector, 200 watt light bulb on Variac, VHS video tape of Sunspots on 11/01/90 from Van Allen rooftop.
Procedure :	Lay the light bulb on the overhead projector and focus so that a clear image of the filament is produced. Turn off the overhead projector and turn up the Variac until the filament glows with a yellow to orange color. Leave the Variac at that setting and turn on the overhead projector. Since the light coming out of the overhead projector is produced by a hotter filament the filament image of the bulb will again appear dark or non-glowing. (A Sun Spot).

References

Thomas K. McCarthy, "A Doorway Can Be A Sunspot, Too!", TPT, Vol. 35, # 6, Sept. 1997, p. 334.

Thomas O. Callaway, Harry D. Downing, and Glen T. Clayton, "Classroom Demonstration of Sunspots", TPT, Vol. 20, # 3, Mar. 1982, p. 171.

"Astronomy Demonstrations," PIRA News, Vol. 9, No. 3, p. 21, (January 1995).

H.J. Press, "Image of the Sun," Giant Book of Science Experiments, p. 11.

Mail Questions and Comments to: Dale Stille