what is the difference between wave and vibration?

[dzhoucam]

It seems both of them have the same mathmatic expression. I wonder what is the physical difference between them. Thanks.

 

[MikeyP]

It all depends on your precise definition of "wave" and "vibration". I would say that vibrations are the physical kinematic motions caused by waves in elastic solids. I would not call electromagnetic or fluid waves "vibrations".

M

--
Dr Michael F Platten

 

[hacksaw]

in the simplest terms waves involve propagation whilst vibrations do not. at the same time it is not always possible to separate the two.

 

[jheidt2543]

Could the wave length be used to define the two? I think of waves (of whatever kind) as having a long wavelength, in the range of feet. Vibrations as have short wavelengths in the range of inches and less. As noted above, the transition is difficult to define.

 

[electricpete]

I agree with all who wrote before. Especially Mikeyp... they are both fuzzy terms which can be used many different ways depending on the context.

One other aspect would be distributed (continuous space) mass spring systems vs lumped (discrete space) systems. Waves I think apply only to continuous systems. Vibration could be either.

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[MikeyP]

electricpete, I was thinking the same thing. Although many people use FE (a discrete "lumped parameter" model) to simulate waves by approximating a continuous medium with lots and lots of small lumped elements.

M

--
Dr Michael F Platten

 

[hacksaw]

would only add the obvious that waves are not confined to elastic solids...

the lumped element approximation can only be made in cases where the wavelength is greater than the dimensions of your system