1C30.57 - Balance A Stick - Reaction Time

Code Number:
1C30.57
Demo Title:
Balance A Stick - Reaction Time
Condition:
Excellent
Principle:
Balancing and Reaction Time
Area of Study:
Mechanics
Equipment:
Meter Stick, Pencil, Movable Masses, Object that is weighted on one end.
Procedure:

You will find a meter stick or other long uniform object easy to balance vertically on your palm.  A shorter stick such as a pencil can not be balanced vertically for any length of time.

References:
  • Leonid Minkin, Anthony C. Zable, "From Balancing a Stick to Tightrope Walking: How Added Mass Influences the Act of Balancing", TPT, Vol. 60, #7, Oct. 2022, p. 549.
  • Robert H. Romer, "Balancing Sticks and Reaction Times Revisited", TPT, Vol. 43, #2, Feb. 2005, p. 68.
  • H.T. Hudson, "Reaction Time as Measured by Balancing a Stick", TPT, Vol. 42, #8, Nov. 2004, p. 506.

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