Demonstrations

Reaction Times

Code Number :	1C30.55
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: U of Iowa Disclaimer All Rights Reserved.
Condition :	Fair
Principle :	Human Reaction Time
Area of Study :	Mechanics
Equipment :	Ruler, Long Strips of Cardboard, Dollar Bill.
Procedure :	The instructor takes the ruler and holds it in the air. A student then comes up and puts his fingers at the lower end of the ruler so that he may catch the ruler as soon as the instructor lets go. The ruler should fall 50 to 75 cm. before the student can react and catch the ruler. Cardboard strips may be used in place of the ruler. A variation of this is to use a dollar bill. The student should not be able to catch the bill if this is done properly.

References

Robert H. Romer, "Balancing Sticks and Reaction Times Revisited", TPT, Vol. 43, # 2, Feb. 2005, p. 68- 69.

H.T. Hudson, "Reaction Time as Measured by Balancing a Stick", TPT, Vol. 42, # 8, Nov. 2004, p. 506.

Joseph L. Spradley, "Meter - Stick Mechanics", TPT, Vol. 28, # 5, May 1990, p. 312.

Bill Crummett, "Measurements of Acceleration Due to Gravity," TPT, Vol. 28, # 5, p. 291, (May 1990).

David G. Willey, "Measuring Reaction Time", TPT, Vol. 23, # 5, May 1985, p. 314.

H.T. Hudson, "Reaction Time as Measured by Balancing a Stick", TPT, Vol. 22, # 4, Apr. 1984, p. 245.

James Watson, Jr., Nancy T. Watson, "Pocketbook Science", TPT, Vol. 20, # 4, Apr. 1982, p. 235.

William Schnippert, "Catch a Dollar Bill", TPT, Vol. 14, # 3, March 1976, p. 177.

D. Rae Carpenter, Jr., "Who Would Like to Have a Buck?", TPT, Vol. 14, # 5, May 1976, p. 260.

Marvin Ohriner, "A Fast Buck", TPT, Vol. 4, # 2, Feb. 1966, p. 67.

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

M- 098: "Reaction Time with $ Bill," DICK and RAE Physics Demo Notebook.

Tik Liem, "Catch the Dollar Bill," Investigation to Science Inquiry, p. 447- 448.

Adolf Cortel, "Simple Experiments on the Physics of Vision: The Retina", Physics Education, Vol. 40 (4), July 2005, p. 325.

Ron Hipschman, "Reaction Time," Exploratorium Cookbook II, 122-1 - 122-2, (1980).

Janice VanCleave, "Oops!" Guide to More of the Best Science Fair Projects, p. 58.

Janice VanCleave, "18, Oops!" Help, My Science Project is Due Tomorrow! p. 40.

"Reaction Time Chain," Physics From the Junk Drawer, 3rd Edition, The Science House, North Carolina State University, p. 7.

Mail Questions and Comments to: Dale Stille