10A05.10 - Balloon in a Bottle Experiment

Place the body of the balloon in the bottle and stretch the opening over the mouth of the bottle.  If your finger is over the vent hole in the bottom of the bottle you will not be able to blow up the balloon.  Also, if you uncover the hole and then blow up the balloon, you will be able to keep it inflated by covering the hole with your finger.
You can make a pencil jump out of the bottle if you use a wide mouth flask so that the balloon collapses quickly when you take your finger off the hole.
Code Number:
10A05.10
Demo Title:
Balloon in a Bottle Experiment
Condition:
Excellent
Principle:
Air Pressure
Area of Study:
Heat and Fluids
Equipment:
Soda Bottle with hole in the bottom, balloons.
Procedure:

See also 2B30.07 in Heat and Fluids

Place the body of the balloon in the bottle and stretch the opening over the mouth of the bottle.  If your finger is over the vent hole in the bottom of the bottle you will not be able to blow up the balloon.  Also, if you uncover the hole and then blow up the balloon, you will be able to keep it inflated by covering the hole with your finger.

You can make a pencil jump out of the bottle if you use a wide mouth flask so that the balloon collapses quickly when you take your finger off the hole.

References:
  • Martin Gardner, "The Jumping Pencil", TPT, Vol. 37, # 3, March 1999, p. 178.
  • Gholamreza Shamsipour, "Simple Experiments for Teaching Air Pressure", TPT, Vol. 44, # 9, Dec. 2006, p. 576.

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