Thu May 24, 2012 By:

The velocity of sound depends on its pressure and density. obtain the relation between velocity , pressure and density.

Expert Reply
Thu May 24, 2012

the speed of sound c is given by the Newton-Laplace equation:


P is a coefficient of stiffness, the bulk modulus (or the modulus of bulk elasticity for gases),
 is the density

Thus the speed of sound increases with the stiffness (the resistance of an elastic body to deformation by an applied force) of the material, and decreases with the density. For ideal gases the bulk modulus P is simply the gas pressure multiplied by the adiabatic index.

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