3A95.85 - Firehose Instability

Code Number:
Demo Title:
Firehose Instability
Instability and Chaos
Area of Study:
Tygon hose, paper sheet or flag, bell on a 6 V. battery, Rayleigh-Taylor Instability demo, Edge Tone Generator demo.

See also 3A95.85 in Oscillations/Acoustics and 1N22.51 in Mechanics.

Attach the Tygon hose to the compressed air in the classroom.  Hold it at least 18 inches away from the end and turn on the air full blast.  The end of the hose will show a chaotic movement.

The paper sheet or flag, bell on the battery, Rayleigh-Taylor demo, and the edge tone demo are all examples of types of instabilities under the right conditions.

  • Bill Franklin, "The Reaction Force on a Hose", Teaching About Impulse and Momentum, p. 3.12.
  • Bill Franklin, "Hoses", Teaching About Impulse and Momentum, p. 2.10 - 2.11.
  • Julien Clinton Sprott, "2.25. Firehose Instability", Physics Demonstrations - A Sourcebook for Teachers of Physics, p. 131 - 132.

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