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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?
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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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