3B60.13 - Beats - Organ Pipes

Take the two matched organ pipes and set them to the same frequency. Using a gentle air flow, change the plunger distance in one of the tubes and listen to the beats. The whistles are used exactly like the organ pipes described above.
Code Number:
3B60.13
Demo Title:
Beats - Organ Pipes
Condition:
Good
Principle:
Constructive & Destructive Interference of Sound Waves
Area of Study:
Acoustics
Equipment:
Organ pipes (wooden), Slide whistles (pair, mounted).
Procedure:

Take the two matched organ pipes and set them to the same frequency. Using a gentle air flow, change the plunger distance in one of the tubes and listen to the beats. The whistles are used exactly like the organ pipes described above.  

References:
  • Niran Charoenlu, "Easy Beats", TPT, Vol. 35, # 8, Nov. 1997, p. 490. 
  • Borislaw Bilash II, David Maiullo, "You Can't Beat a Singing Rod", A Demo a Day: A Year of Physics Demonstrations, p. 221.


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