Why Can We Hear Around Corners But Not See Around Them?

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Diffraction explains why we can hear around corners but not see around them. Sound waves, with wavelengths typically a few meters, can bend around obstacles like doorways, allowing us to hear sounds from different directions. In contrast, visible light has a much shorter wavelength of about 400 nanometers, which prevents it from diffracting around corners in the same way. While electromagnetic radiation with longer wavelengths, such as radio waves, can bend around obstacles, visible light behaves more like a beam. Thus, the ability to hear around corners is due to the longer wavelengths of sound compared to the shorter wavelengths of light.
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If light is a wave then how come we can hear around a corner but not see around a corner?
 
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harhar said:
If light is a wave then how come we can hear around a corner but not see around a corner?

Diffraction is the key. This occurs when a wave passes through a gap OF A SIMILAR SIZE to the wavelength concerned. Sound waves diffract around doorways (similar size wave), but light doesn't as it has a wavelength of only a few hundred nanometers.
 
harhar said:
If light is a wave then how come we can hear around a corner but not see around a corner?

Because the typical wavelength of visible light is waaaaaaay shorter than the typical wavelength of sound. It does mean that if you have EM radiation that has long wavelengths, it can go "around a corner", and voila, you have radio waves!

Zz.
 
The wavelength is sound is typically a few meters, long enough to bend around obstacles such as doors and hallways. Also, many sound sources emit sound more or less radially (in all directions).

Light sources are more often more beam-like and the wavelength of visible light is about 400 nanometers. You won't notice diffraction (the 'bending' of waves around corners) unless the obstacles have about the same dimensions as the wavelength. That's why we usually don't notice it, but if light passes through a small slit it does 'bend' and we can 'see around a corner'.
 
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