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This corrugated plastic drainage pipe works like the smaller hose pipe variety, except you'd best allow a twenty-foot spinning diameter. You will also get dizzy spinning it. Centrifugal force generates quite a suction at your hands and the sound is correspondingly lower. I was not able to generate more than two notes. I read about it on the web (this person used swimming pool cleaner hose). I have some swimming pool cleaner hose now. Much easier!


Mark Silverman presents a study of whirlies in his book, Waves and Grains.


Giant Whirly

Addendum: I asked the students if they were familiar with the whirly.  Some described how to make it sound off.  How does that work, I asked. Is air rushing through it?  I had a student whirl the whirly and hold packing popcorn up to the still end. Remarkably the popcorn gets sucked up and blown out the other end, much to the delight of students.  I tell them this is the result of Newton's first law.  The tube wall pushes the popcorn, which otherwise moves in a straight line toward the moving end of the tube.  Vacuum cleaners will never look the same.