# 1F20.40 - Stick and Wine Glasses

Code Number:
1F20.40
Demo Title:
Stick and Wine Glasses
Condition:
Good
Principle:
Inertia of Mass
Area of Study:
Mechanics
Equipment:
Wine glasses with colored water, 1/2" to 1" wooden dowels, window sashing, 24" aluminum rod, pins.
Procedure:

Put a pin in each end of the sashing or the dowel and rest a pin on each wine glass.  The object is to break the dowel with the aluminum rod without disturbing the wine glasses.

NOTE:  Since there will be flying pieces of wood protective clothing and eyewear is a must.

Another version of this experiment replaces the wine glasses with eggs in egg cups.  Practice or you may end up with " egg on your face"!

Another version is to replace the wine glasses with loops of paper with a 4 inch diameter and a couple of knives that can be clamped to a table.  Clamp the knives edge up.  Then place the loops over the blades and place the dowel in the loops.  The loops will remain intact when the dowel is broken.

References:
• Ernie McFarland, Tom Kehn, "The Fantastic Physics Fun Show", TPT, Vol. 34, # 8, Nov. 1996, p. 512.
• Ernie McFarland, Tom Kehn,  "Breaking Broomstick",  TPT, Vol. 34, # 8, p. 514, Nov. 1996.
• Karl C. Mamola, Joseph T. Pollock,  "The Breaking Broomstick Demonstration",  TPT, Vol. 32, # 4, p. 230, April 1993.
• Guy Vandegrift, "Transverse Bending Waves and the Breaking Broomstick Demonstration", AJP, Vol. 65, # 6, June 1997, p. 505.
• Ling Tsai,  "The Relation Between Gravitational Mass, Inertial Mass, and Velocity",  AJP, 340, April 1986.
• M- 250:  "Break String with Large Mass",  DICK and RAE Physics Demo Notebook.
• M- 258:  "Hanging Mass and Stick",  DICK and RAE Physics Demo Notebook.
• Bob Friedhoffer, "Tap-L discussions", 2/4/05.

Disclaimer: These demonstrations are provided only for illustrative use by persons affiliated with The University of Iowa and only under the direction of a trained instructor or physicist.  The University of Iowa is not responsible for demonstrations performed by those using their own equipment or who choose to use this reference material for their own purpose.  The demonstrations included here are within the public domain and can be found in materials contained in libraries, bookstores, and through electronic sources.  Performing all or any portion of any of these demonstrations, with or without revisions not depicted here entails inherent risks.  These risks include, without limitation, bodily injury (and possibly death), including risks to health that may be temporary or permanent and that may exacerbate a pre-existing medical condition; and property loss or damage.  Anyone performing any part of these demonstrations, even with revisions, knowingly and voluntarily assumes all risks associated with them.