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प्रश्न
When we put our ear to a railway line, we can hear the sound of an approaching train even when the train is far off but its sound cannot be heard through the air. Why?
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उत्तर
Sound travels about 15 times faster in iron or steel than in air. We can hear the sound of an approaching train by putting our ear to the railway line made of iron or steel even when the train is far away because the sound produced by the motion of train’s wheels over the railway line is carried away quickly by the steel rails than in air.
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संबंधित प्रश्न
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Calculate the speed of a sound wave whose frequency is 2 kHz and wavelength 65 cm.
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The drawing shows a ship 800 m from a cliff. A gun is fixed on the ship. After 5 seconds the people at the front of the ship hear the sound of the gun again.
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