A sound wave is a longitudinal wave. The velocity of a longitudinal wave (in general) in a medium is given by the relation v = \(\sqrt{\frac E\rho}\), Where E is the modulus of elasticity and ρ is the density of the medium. From this relation, it is clear that velocity not only depends upon the density but also on the elasticity of the medium. So, the velocity of propagation of any longitudinal wave in any medium depends upon the ratio of modulus of elasticity and density. For solid, the ratio \(\frac E\rho\) is much greater due to its high elasticity than for a gas or a liquid due to liquid's low elasticity. Hence, the velocity of longitudinal wave (e.g. sound wave) in solids is greater than in liquids and gases as V_s > V_l > V_g