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प्रश्न
Explain by giving a scientific reason.
We cannot hear the echo produced in a classroom.
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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
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Assertion: The sound which we hear again is called Echo.
Reason: The sensation of sound (Echo) persists in our brain for about 1 s.
