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प्रश्न
Answer the following question in your own words.
What is an echo?
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उत्तर
An echo is the reflection of sound waves off a surface, such as a wall, mountain, or building, that returns to the listener after a delay. It occurs when the reflected sound reaches the ear after at least 0.1 seconds, allowing the listener to distinguish it from the original sound. Echoes are commonly experienced in large, empty spaces or near hard, smooth surfaces.
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संबंधित प्रश्न
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