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प्रश्न
If you want to hear a train approaching from far away, why is it more convenient to put the ear to the track?
उत्तर
It is more convenient to put the ear to the track to hear a train approaching from far away because sound travels faster in solids than in air because the speed of sound is directly proportional to the density of the material medium. In this case, the density of railway track is higher than air. Hence, sound waves travel faster through the railway track.
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संबंधित प्रश्न
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(a) 5100 m/s
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Numerical problems:
Two persons are at opposite ends of a steel rod. One strikes the end of the rod with a stone. Find the ratio of time taken by the sound wave in the air and in steel to reach the second person. (Sound of speed in steel = 5960 ms-1, Sound of speed in air = 344 ms-1).
