Why Do People Put Their Ears to Railroad Tracks to Detect Approaching Trains?

AI Thread Summary
Placing ears on railroad tracks allows individuals to detect approaching trains due to the efficient transmission of sound waves through metal. Sound travels faster and farther in solid materials like steel compared to air, making it easier to hear distant trains. The vibrations from the train create disturbances in the track, which can be detected more effectively than through air. This method provides an early warning system, enhancing safety for those near the tracks. Understanding the properties of sound in different mediums highlights the advantages of using metal for sound detection.
m.l.
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Homework Statement


People put their ears to a railroad track to get an early warning of an approaching train. why did this work.


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written response.


The Attempt at a Solution


Sound waves can travel a long way along an undisturbed metal rod?
 
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The rod has to be disturbed for any sound to be carried along it. Apart from traveling a long way in the rail, what other property does sound have in the metal that is greater than in air that would be an advantage?
 

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