Organ pipes (wooden), Slide whistles (pair, mounted)

Code Number: 3B60.13

Demo Title: Beats - Organ Pipes

Condition: Good

Principle: Constructive & Destructive Interference of Sound Waves

Area of Study: Oscillations & 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.

3B60.13 - Beats - Organ Pipes

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