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प्रश्न
What is meant by an echo? Explain.
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उत्तर
An echo is a repetition of sound produced by the reflection of sound waves from a wall, mountain or other obstructing surfaces. The minimum distance from a sound-reflecting wall to hear an echo at 20°C is 17.2 meter.
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संबंधित प्रश्न
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(i) A man stands at a distance of 68 m from a cliff and fires a gun. After what time interval will he hear the echo, if the speed of sound in air is 340 ms−1?
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What is mean by the reflection of sound?
