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According to Wikipedia and validated by a clever thought experiment here, sound waves can be transverse as well as longitudinal, if they're propagating through a solid. Consider my mind blown and my curiosity piqued. However, is this a phenomenon we can hear? And is there any reason these waves would be different from longitudinal sound waves?

Understandably, this kind of sound wouldn't travel through the normal path as that requires traveling through the air to get to the eardrum. Bone conduction headphones seem to offer a promising avenue, but I see no reason that those sound waves wouldn't be longitudinal.

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  • $\begingroup$ i think i agree with neils that, if the OP means sound waves in air, the answer is "n0" because there are no transverse sound waves in air of any significant amplitude. sound waves in air are purely longitudinal because they are essentially compression waves. $\endgroup$ – robert bristow-johnson Jan 5 '18 at 4:54
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    $\begingroup$ Looks to me like a question in biology. The eardrum definitely would not respond to transverse waves even if in direct touch with a solid carrying these waves. Bone conducting can carry trasverse waves but I believe bone conducting hearing is also based on longitudinal waves although this type of hearing circumvents the eardrum. $\endgroup$ – npojo Jan 5 '18 at 8:09
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sound transmission through a solid can occur by either compressive waves or shear (transverse) waves because a solid is capable of sustaining shear stresses. sound transmission through air is exclusively by compression waves because air cannot sustain shear stresses.

You can certainly hear both sorts of waves by pressing your ear against, for example, a steel girder which is carrying both sorts of waves because someone on the other end of the girder is whacking it with a hammer, but the amount of each you will hear depends on details of how exactly your ear is coupled to the girder.

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  • $\begingroup$ +1 Good answer except that shear waves can exist in a fluid. See Stokes second problem in which an infinite plate vibrates in its own plane setting up damped shear waves in the fluid. $\endgroup$ – Deep Jan 5 '18 at 4:38
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    $\begingroup$ I always felt that the insupportability of shear stresses in water prevented the transmission of shear waves in it; can you give me some hints on how this is possible? best regards, niels $\endgroup$ – niels nielsen Jan 5 '18 at 4:40
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    $\begingroup$ Ok my bad, I am wrong in calling it a wave because there is no restoring force in the transverse direction. This is true of Newtonian fluids. In non-Newtonian fluids such as for example viscoelastic fluids there would be elastic restoring forces in transverse direction I think. Your answer is fully correct as regards Newtonian fluids which is what the OP seems to have in mind. $\endgroup$ – Deep Jan 5 '18 at 4:44

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