1C30.55 - Reaction Times

Code Number:
Demo Title:
Reaction Times
Human Reaction Time
Area of Study:
Ruler, Long Strips of Cardboard, Dollar Bill.

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.

  • Praveen Pathak, "Human Reaction Time Measurement Using a Smartphone", TPT, Vol. 60, #9, Dec. 2022, p. 723.
  • Thomas B. Greenslade Jr., "Human Reaction Times", TPT, Vol. 59, #3, March 2021, p. 205.
  • 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, May 1990, p. 291.
  • 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. and Nancy T. Watson, "Pocketbook Science", TPT, Vol. 20, #4, Apr. 1982, p. 235.
  • D. Rae Carpenter, Jr., "Who Would Like to Have a Buck?", TPT, Vol. 14, #5, May 1976, p. 260.
  • William Schnippert, "Catch a Dollar Bill", TPT, Vol. 14, #3, Mar. 1976, p. 177.
  • 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, "17.17. Catch the Dollar Bill", Investigation to Science Inquiry, p. 447.
  • Tik Liem, "17.18. How Fast Can You React?", Investigation to Science Inquiry, p. 448.
  • Julien Clinton Sprott, "1.2, Reaction Time", Physics Demonstrations, ISBN 0-299-21580-6, p. 6.
  • Adolf Cortel, "Simple Experiments on the Physics of Vision: The Retina", Physics Education, Vol. 40 #4, July 2005, p. 325.
  • Martin Gardner, "Catch The Bill", Entertaining Science Experiments with Everyday Objects, p. 24.
  • Vicki Cobb and Kathy Darling, "Quick Buck", Bet You Can't!, p. 112.
  • Borislaw Bilash II and David Maiullo, "Money from the Sky", A Demo a Day: A Year of Physics Demonstrations, p. 34.
  • Ron Hipschman, "Reaction Time", Exploratorium Cookbook II, 1980, p. 122-1 - 122-2.
  • Janice VanCleave, "12, 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.
  • The Science House, North Carolina State University, "Reaction Time Chain", Physics From the Junk Drawer, 3rd Edition, p. 7.

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