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Sound waves in the air are always longitudinal because

Options

  1. AOf the inherent characteristics of sound waves in air
  2. BAir does not have a modulus of rigidity
  3. CAir is a mixture of several gases
  4. DDensity of air is very small

Correct answer

B. Air does not have a modulus of rigidity

Step-by-step solution

In the transmission of sound through air, there is no actual movement of air from the sound producing body to our ear. The air layers only vibrate back and forth, and transfer the sound energy from one layer to the next layer till it reaches our ear. This back and forth motion causes the compression and rarefaction in a sound wave. This motion is along the direction of propagation of sound and hence, the sound waves are longitudinal. Note that the layers of air consist of molecules of gases. Note that the layers of

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