PURPOSE: To demonstrate interference of sound with two coherent sound sources.
DESCRIPTION: The oscillator-amplifier is set to approximately 3000 Hz, with identical signals being applied to both loudspeakers. Rotating the loudspeakers past the listeners allows them to observe the interference pattern by hearing the alternating maxima and minima in the intensity pattern.
REFERENCES: (PIRA 3B55.10) See also demonstration H2-22: INTERFERENCE TRANSPARENCIES, a Moire pattern model of this experiment, and H2-24: AUDIBLE YOUNG'S EXPERIMENT - MICROPHONE AND OSCILLOSCOPE, for a more quantitative investigation of two-source interference. See also several film loops using the ripple tank.
EQUIPMENT: Loudspeakers on rotating boom permanently mounted on oscillator-amplifier.
SETUP TIME: None.
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