Velocity of longitudinal waves in a solid.

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RazerM
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Homework Statement


Our lecturer gave us a general equation for velocity of waves; (where [itex]c=[/itex] wave velocity)
[tex]c= \sqrt{\frac{\textrm{springiness}}{\textrm{massiness}}}[/tex]
(Excuse the terms, I'd personally rather have been given the equations here..)

So for transverse waves on a string/wire (where [itex]T=[/itex] Tension and [itex]\mu=[/itex] mass per unit length)
[tex]c= \sqrt{\frac{T}{\mu}}[/tex]
and for longitudinal waves in a gas (where[itex]B_{ad}=[/itex] the adiabatic bulk modulus and [itex]\rho=[/itex] density)
[tex]c= \sqrt{\frac{B_{ad}}{\rho}}[/tex]


Where I am stuck is longitudinal waves in a solid, I'm assuming massiness = [itex]\rho[/itex] but am unsure about springiness.

Homework Equations


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The Attempt at a Solution


So for longitudinal waves in a solid; solving for the dimensions of springiness appears to show that springiness is in Newtons but how does Force correlate to a wave through a solid, or am I missing the point completely?
 
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hmm, I think you made a mistake in that unit calculation. I get Pascals (N/m^2), a unit of pressure... but I'm not sure what physical quantity that corresponds to, since solids don't really have pressure in the same sense as gasses. This is a particular area of physics in which my knowledge is sadly lacking.

Isn't there a bulk modulus for solids?