A wave on a string can have polarization because the string can be distorted in more than one "direction". It can have an amplitude and a direction of distortion.
Similarly, light has polarization because it is a distortion or variation of a vector-field electric and magnetic fields are vector-fields. Perhaps your teacher meant, that you can choose a direction for a wave on a string for example, thereby constraining it.
So in this sense, if there is enough freedom for the wave i. It would be difficult to imagine a polarisation of a longitudinal wave, but this certainly is true for transverse waves. The air couples weakly to transverse waves and so does your ear! Hence, we often consider sound waves in the air as longitudinal only, that would not be polarised. Generally, though, sound waves can certainly be transverse and polarised. See for example a shear-stress mode in quartz. And usually they run in all directions.
When You polarize light - You let waves go just in one plane. But air waves are just vibration of the same matter. You can not take air waves just in one plane. It is simple to understand geometrically: light waves vibrations are 3D which, can be confined to a 2D plane. But sound waves vibration are 1D and they cannot be confined to particular 2D plane. Of course sound can be limited or controlled by barriers.
Sound can be absorbed and reflected, and even refracted. But it's true that sound is not typically polarized when propagating in air. The reason is, as stated by others answering this question, that air cannot transmit shear forces effectively: all it can transmit is pressure forces.
Sound that is, acoustic waves, which are elastic deformations of a medium can be polarized in a solid, in a viscous liquid, or on a surface, because those media are able to transmit shear forces in addition to pressure forces.
Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? It is therefore possible to confine the vibrations to a single plane.
Or put another way an unpolarised transverse wave is a 3D shape, it is therefore possible to confine it to a 2D shape a plane. The vibrations of a longitudinal wave occur along a single line, it is therefore not possible to confine that to a plane, i. Why can't sound waves be polarized? Physics Light and Reflection Color and Polarization. Daniel W. Nov 17, Sound waves are longitudinal. Transverse: vibrations perpendicular to the direction of travel of the wave.
Light waves are not considered mechanical waves because they don't involve the motion of matter. Most of the mathematics and properties of mechanical waves apply to light waves.
Light waves are different from mechanical waves, however, because they can travel through a vacuum. Light waves are just one type of electromagnetic wave. Other electromagnetic waves include the microwaves in your oven, radio waves, and X-rays. Light waves are regarded as a varying electric field E coupled with a varying magnetic field B , at right angles to each other and to the direction of travel.
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