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Question
Two sources of sound are separated by a distance of 4 m. They both emit sound with the same amplitude and frequency (330 Hz), but they are 180° out of phase. At what points between the two sources, will the sound intensity be maximum?
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Solution
∴ λ = `"v"/"n"=330/330` = 1 m
The path difference between two sources of sound is zero when they are directly in the centre of each other. However, because the waves are 180° out of phase, two maxima on either side should be at a distance of `λ/4` from the centre. Other maxima will be located each `λ/2` along the way.
As a result, the maximum sound intensity will be ± 0.25, ± 0.75, ± 1.25, and ± 1.75 m from the point at the centre.
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