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प्रश्न
On which day, a hot day or a cold day, an echo is heard sooner ? Give reason for your answer.
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उत्तर
An echo is heard sooner on a hot day because the speed of sound in air increases with increase in temperature of the propagating medium. Therefore, the speed of sound in air is faster on a hot day and thus echo is heard sooner.
संबंधित प्रश्न
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