Derive the frequencies of vibration expression of a tube open at both ends, in terms of v, L, and n (where v is the speed of sound in the air inside the tube - ~340 m/s, L is the length of the tube, and n is an integer 1, 2, 3...).
You have a Whirly Tube that is 0.6 m long and is open at both ends. First, use the above expression for the standing wave frequencies in tubes to predict the frequencies of the Whirly Tube. Test your prediction with a cell phone tuner App outside (you can get about three distinct frequency sounds).