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प्रश्न
How is sound perceived by us?
उत्तर
Sound requires a material medium for its propagation. It is produced when a body vibrates. The vibrations produced at a point are transmitted in the medium (air) from one point to the next and so on in the form of mechanical waves which produce compressions and rarefactions in air. These compressions and rarefactions produce vibrations in the eardrum which are perceived by us as sound.
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