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प्रश्न
Velocity of sound in air is 332 m s−1. Its velocity in vacuum will be
विकल्प
> 332 m s−1
= 332 m s−1
< 332 m s−1
meaningless.
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उत्तर
meaningless
Sound wave is a mechanical wave; this means that it needs a medium to travel. Thus, its velocity in vacuum is meaningless.
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