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प्रश्न
Explain by giving a scientific reason.
We cannot hear the echo produced in a classroom.
उत्तर
- An echo is a sound produced when the original sound is reflected by the walls of a given room. For instance, in a small room If there are hard walls there will be an echo of sound bouncing off the wall but because the sound bouncing is so close to the original, it is harder to detect the echo produced.
- A room which is having a dimension greater than 17.2 m will produce an echo in that room.
- The dimensions of a classroom usually do not exceed 17.2 m, so echo is not produced in a classroom. So, in the case of a classroom, no echo is produced in a classroom.
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संबंधित प्रश्न
Explain why, the flash of lightning reaches us first and the sound of thunder is heard a little later.
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Answer the following question in your own words.
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What is the minimum distance needed for an echo?
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Answer the following question in your own words.
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Rohan conducted experiments on echo in different media. He observed that a minimum distance of 'x' meters is required for the echo to be heard in oxygen and 'y' meters in benzene. Compare 'x' and 'y'. Justify your answer.
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Speed of sound in benzene: 200 ms-1
