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The sound of distant horses can br heard...

The sound of distant horses can br heard by applying the ear to the ground whereas it is inaudible if the ear is held a little distance above the ground. Explain.

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We know that loudness is directly proportional to the density of the medium. The density of ground is much higher than that of air. Thus, the sound of distant horses, when conveyed through ground, is louder than when through air. Therefore, by applying ear to the ground, we can hear this sound. But when the ear is a little distance above the ground, the sound travels through air and is hardly audible.
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PRADEEP-SOUND-Short Answer
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