Question

Light waves can be polarized while sound waves cannot why

Answer 1

Only transverse waves can be polarised. Longitudinal waves (sound waves in air) cannot be polarised.

The reason that only transverse waves can be polarised is that their vibrations can be potentially occur in all directions perpendicular to the direction of travel. It is therefore possible to continue the vibrations to a single plane.

The vibrations of a longitudinal wave occur along a single line, it is therefore not possible to confine that to a plane.