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प्रश्न
An observer stands at a certain distance away from a cliff and produces a loud sound. He hears the echo of the sound after 1.8 s. Calculate the distance between the cliff and the observer if the velocity of sound in air is 340 m−1.
उत्तर
We know s = `"d"/"t"`
⇒ d = s × t
⇒ d = `340xx1.8/2`
∴ d = 306 m.
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