Vibration

I was studying physics when I received an sms from Sayonara.

My arms were on the table, supporting my head. I felt the vibration first because I heard the beep from the handphone.

I think that somehow illustrates that sound travels faster in solids compared to in air.

But then ah hor.....I'm reluctant to think of the vibration as sound, because a sound is a longitudinal wave, and I'm not sure whether the vibration of my table is longitudinal.

I would argue that the vibration of the wooden table is transverse, hence the to-and-fro motion about the equilibrium position pushes the air molecules and produces a longitudinal wave motion in the air molecules, thus producing the "sound" of vibration of table I heard, which is distinct from the beep sound of my handphone.

Why not longitudinal leih? Because u see har.....I put my handphone on top of, and at one corner of the table. If the table is to be set into vibration, then the direction of the vibration of the handphone has to be from handphone to table, which mean the direction is perpendicular toe surface of the table.

My hand, which is at other points of the table, detected the vibration. Hence the direction of PROPOGATION of energy/vibration/wave is in every line on the plane of the surface of the table. I felt the vibration because the medium particles (particles of the table surface) is pushing against my palm (guess) in the direction perpendicular to the table surface.

Since the direction of vibration is perpendicular to the surface of the table, and the line of direction of propogation of the wave (with the table as the medium) is on the plane of the table surface, therefore the direction of vibration is perpendicular to the direction of propogation of the wave, which satisfies the definition of a transverse wave.

Therefore the wave travelling on the surface of the table is a transverse wave.

But of course lah hor...I don't think the explanation is this simple lah....because this time the wave is not linear like the wave in a slinky spring. Suppose I put my palm under the table just beneath the handphone, I can also feel the vibration. Then the direction of propogation of the wave would be parallel to the direction of vibration of medium particle, i.e. longitudinal wave. So there is many individual waves superposing with one another in the table?

Anyway, just because I felt the vibration earlier than the sound of the handphone, doesn't mean "sound" (I used inverted commas because if the wave in the solid is transverse, then the wave would not satisfiy the definition of "sound waves") travels faster in solid, because it could be that I perceived the sound later because the mind gives priority to stimuli detected my the hand, then only the ear?

This is why I think it's important to study Biology. I have a lot to write on this, but my language fails me.

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Kindly doubt and challenge and correct me, after all what I've written is just a guess.