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प्रश्न
A man standing between two cliffs produces a sound and hears two successive echoes at intervals of 3s and 4s respectively. Calculate the distance between the two cliffs. The speed of sound in the air is 330 ms−1.
उत्तर
∵ Ist echo is heard from the nearest cliff so let its distance be d1
∴ d1 = s × t = `330xx3/2` = 495 m and
∵ IInd echo is heard from the further cliff so let it be d2
∴ d2 = s × t = `330xx4/2` = 660 m
∴ Total distance = 660 + 495 = 1155 m.
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