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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
When a sound is reflected from a distant object, an echo is produced. Let the distance between the reflecting surface and the source of sound production remains the same. Do you hear echo sound on a hotter day?
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Fill in the blank with suitable word :
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Name any two objects which are good reflectors of sound.
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Answer the following question in your own words.
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State two conditions necessary for hearing an echo.
How can you calculate the speed of sound using echo?
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What is an echo? Write the conditions to hear an echo.
Numerical problems:
An echo returned in 3s. What is the distance of the reflecting surface from the source given that the speed of sound is 330 ms-1?
