CBSE Class 10 Answered

1. V_M > V_D

Moisture content increases the speed of sound becuase, speed of sound is inversely propotional to the density, and in dry air density is composed of oxygen and nitrogen molecules and they mass, but when moisture, water molecules and present, they have lower density, since hydrogen and oxygen together will add up to a lower mass. So this mixing of water with dry air reduces the density, hence increases the speed of sound.

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