Question

Sound of frequency 2.0 kHz falls at normal incidence on a high wall in which there is a vertical gap that is 30 cm wide. A man is walking parallel to the wall, on the other side from the source of sound, at a perpendicular distance of 20 m from the wall. Assuming a speed of sound of 340 m/s, over what range of distance would he hear an intensity of sound: (a) more than 50% of the maximum? (b) more than 5% of the maximum? You can consider just the central maximum for this calculation.

Answer 1

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