10A05.15 - Straw into Potato

You should be able to drive a straw clear through a potato if you know this simple trick.  Hold your thumb over the top of the straw when you are driving the straw into the potato.  The air trapped inside the straw will provide the needed rigidity to get the straw through the potato.
Code Number:
10A05.15
Demo Title:
Straw into Potato
Condition:
Excellent
Principle:
Air Pressure
Area of Study:
Fluids
Equipment:
Straws (either large or small diameter), potatoes.
Procedure:

You should be able to drive a straw clear through a potato if you know this simple trick.  Hold your thumb over the top of the straw when you are driving the straw into the potato.  The air trapped inside the straw will provide the needed rigidity to get the straw through the potato.  

References:
  • George Freier, "Drive Straw in Potato-Sense Pressure", DICK and RAE Physics Demo Notebook, F- 030, p. 03-93. 
  • Martin Gardner, "Potato Puncture", Entertaining Science Experiments with Everyday Objects, p. 99. 
  • Janice VanCleave, "55, Straw Drill", Earth Science For Every Kid: 101 Easy Experiments That Really Work, p. 124.
  • Tik L. Liem, "Pierce A Potato With A Straw", Invitations to Science Inquiry - Supplement to 1st and 2nd Ed. p. 116.
  • Julius Sumner Miller, Q41 & A41, Millergrams I – Some Enchanting Questions for Enquiring Minds, p. 34 & 90.

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