• Length of each tube determines tube’s resonance pitch. The longer the tube the lower the pitch. Tone produced by whacking a tube reveals its note of resonance. Resonance pitch can be changed by attaching the plastic end-cap.
  • For additional demo ideas and see: boomwhackers
  • Located in L02, section C2.

Whistling Whirly Tubes


whirly tube

  • Hold handle-side of tube securely and twirl around rapidly in a circle. Tube makes a whistling sound that can be heard long distances, resulting from standing pressure waves that set up in the tube. Pitch of whistle depends on twirling speed, however, because only standing waves produce a whistle, the pitch of the whistle goes from one octave to the next in discrete jumps. See: sound pipe document for further explanation.
  • Can also use tube to demonstrate Bernoulli’s principle. Pressure difference between tube ends results from faster motion of outer end. Pressure differential produces air flow through tube. Stationary end of tube (handle end) acts as a vacuum and will suck up small pieces of paper when outer end is twirling.
  • Located in L02, section C2.

Temperature and Sound

Sound and Temperature Pipes

Copper pipes chime when hit (hang by loop and tap with hard object). Pipes are identical in size and composition, and are therefore identical in pitch.

To see how temperature affects pitch, dip one pipe in liquid nitrogen and cool for 1 minute. Tap both pipes to hear differences in pitch. Caution: DO NOT TOUCH COLD PIPE WITH BARE HANDS. USE CRYO GLOVES. 

Pipes located in L02, section C-1. Ask for assistance with LN2.