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The beam width is proportional to the wavelength $\lambda$ divided by the aperture width $L$. Audible sound frequencies are are in the KHz range with wavelengths between approximately 17 m and 17 mm. Whereas visible light wave lengths are in the micrometer range. So sound apertures would have to be vastly larger than light apertures to achieve similar beam ...

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Wave beams require to have a transversal section of lenght of the same the order of magnitude than the wavelength. Whereas for light, we can get very tiny and focused beams (of $\mu m$ order), for sound the wavenlength (of centimeter or meter order), you cannot get beams s focused. Hence the utility of such beams to either transmit information, or focus ...

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The shape effect on fundamental pitch is slight, but the effect on the overtone series is significant. Most wind instruments have cylindrical shapes for this reason, and also because square cross-section pipes with bends in them are more difficult to fabricate. This is a topic about which a lot has been written in the field of musical instrument acoustics/...

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I believe the question can be rephrased (more clearly) as follows: "when we collide two glass balls (or two steel balls), we hear multiple collisions. The intervals between collisions change from long to short. Why?" Take a look of this video https://www.youtube.com/watch?v=k1id4a4EU4M (Pay attention to time 1:01) when he casually collided the balls you ...

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Assuming that you are driving straight into the building, the observer in the building hears the sound coming from your moving car with frequency shifted due to the Doppler effect. The frequency is given by: $$f_2=\frac{c_s}{c_s-v} f_1$$ Here, $c_s$ is the speed of sound in air and $v$ is the speed of your car. You can find the derivation of the frequency ...

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