Question

Does it make sense to talk about the polarization of a longitudinal wave, such as a sound wave? Why or why not?

Short answer

No, it does not make sense because the sound waves cannot be polarized.

Step-by-step solution

Definition of Longitudinal and Transverse Waves

The waves in which displacement of particles is parallel to the wave propagation direction are referred to as Longitudinal waves.

The waves in which displacement of particles is perpendicular to the wave propagation direction are referred to as Transverse waves.

Determine if polarization is possible in longitudinal waves

One can only talk of the polarization of the transverse waves because then one can say if the oscillations of the fields or particles of the medium occur in a line perpendicular to the direction or propagation or in a diffuse manner. With longitudinal waves, all oscillations are along the line of propagation so one cannot make similar discrimination.

Hence, it does not make sense to talk about polarization of longitudinal wave or sound wave.