3D30.35 - Freq Tube

Code Number:
Demo Title:
Freq Tube
Resonance in Pipes
Area of Study:
Plastic hose (Freq Tubes).

Grasp the tubes by one end and whirl in a circle over your head.  The faster you whirl the tube the higher the frequency.  Note that the sound does not go up steadily but goes up by specific intervals.  Place the cork in one end of the tube and note that no sound is produced.

Some approximate values of our freq tubes.

  Orange Tube Blue Tube
Closed tube 80 Hz. 100 Hz.
Fundamental 160 Hz. 200 Hz.
1st 325 Hz. 430 Hz.
2nd 485 Hz. 630 Hz.
3rd 645 Hz. 830 Hz.
4th 810 Hz. 1030 Hz.
5th 980 Hz. 1270 Hz.

This variation from a Tap-L conversation by Andy Smith.  Take a 5 gallon bucket with a hole drilled in the closed end just large enough for one end of the tube to attach.  Fill a trash can up with water.  Push the open end of the bucket down into the water.  The tube will sing.  Knowing the speed the bucket is pushed down into the water and the ratio of the tube and bucket areas, you can determine the speed the air travels through the tube.  This works on the standard toy version and many other corrugated tubes.

  • Lutz Kasper, Patrik Vogt, "Howling Winds and Swinging Sticks: An Acoustical Analysis", TPT, Vol. 60, #5, May 2022, p. 392.
  • Michael J. Ruiz, "'The '2001' Theme on the Whistling Tube", TPT, Vol. 54, #5, May 2016, p. 310.
  • Terry Toepker, "Beach 'Corrugabugle'", TPT, Vol. 49, #8, Nov. 2011, p. 467.
  • Maria Eva Amorim, Teresa Delmira Sousa, P. Simeão Carvalho, and Adriano Sampaioe Sousa, "A Simple Experiment to Explore Standing Waves in a Flexible Corrugated Sound Tube", TPT, Vol. 49, #6, Sept. 2011, p. 360.
  • Louis H. Cadwell, "Singing Corrugates Pipes, Using Video Cameras to Measure Air Flow", TPT, Vol. 32, #1, Jan. 1994, p. 42.
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  • "W-230: Singing Corrugated Pipe", DICK and RAE Physics Demo Notebook.
  • G. D. Freier and F. J. Anderson, "Se-6", A Demonstration Handbook for Physics.
  • Tik Liem, "The Twirling Bugle", Investigation to Science Inquiry, p. 308.
  • Jodi and Roy McCullough, "Sound with a Five-Tone Twirler", The Role of Toys in Teaching Physics", p. 3.21.
  • Jearl Walker, "3.39. Singing Corrugated Tubes", The Flying Circus of Physics, Ed. 2, p. 162.
  • Jearl Walker, "1.54. Twirl-a-Tune", The Flying Circus of Physics with Answers.
  • Robert Ehrlich, "J.7. Harmonic Frequencies in a Corrugated Tube", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 132 - 134.
  • Paul Doherty, "Sounds Like Fun", Presentation for the 2004 AAPT Meeting, Sacramento, CA.
  • "Corruga Horn", Physics From the Junk Drawer, 3rd Edition, The Science House, North Carolina State University, p. 45.

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