# Relationship between density and velocity of sound

### Speed of sound and density relation? | Physics Forums SE question, the speed of sound is given by the formula: . bulk modulus, may be in some expressions for the speed of sound, but always together with density. In case of air the speed of sound is given by v=sqrt[(gamma)P/d]. Gamma is ratio of specific heat at constant pressure to specific heat at constant volume. For air. Explain whether or not the speed of sound is constant for all materials. elasticity and density are and what relationship they have to the speed of sound. In general, the bond strength between particles is strongest in solid materials and is.

## Speed of sound

Measurements were made of gunshots from a number of local landmarks, including North Ockendon church. The distance was known by triangulationand thus the speed that the sound had travelled was calculated.

In real material terms, the spheres represent the material's molecules and the springs represent the bonds between them. Sound passes through the system by compressing and expanding the springs, transmitting the acoustic energy to neighboring spheres.

### Why does sound wave travel faster in a denser medium whereas light travels slower?

This helps transmit the energy in-turn to the neighboring sphere's springs bondsand so on. In a real material, the stiffness of the springs is known as the " elastic modulus ", and the mass corresponds to the material density. Given that all other things being equal ceteris paribussound will travel slower in spongy materialsand faster in stiffer ones.

Effects like dispersion and reflection can also be understood using this model. Similarly, sound travels about 1. At the same time, "compression-type" sound will travel faster in solids than in liquids, and faster in liquids than in gases, because the solids are more difficult to compress than liquids, while liquids in turn are more difficult to compress than gases.

Some textbooks mistakenly state that the speed of sound increases with density. This notion is illustrated by presenting data for three materials, such as air, water and steel, which also have vastly different compressibility, more which making up for the density differences. An illustrative example of the two effects is that sound travels only 4. The reason is that the larger density of water, which works to slow sound in water relative to air, nearly makes up for the compressibility differences in the two media.

## Why does sound wave travel faster in a denser medium whereas light travels slower?

A practical example can be observed in Edinburgh when the "One o' Clock Gun" is fired at the eastern end of Edinburgh Castle. Standing at the base of the western end of the Castle Rock, the sound of the Gun can be heard through the rock, slightly before it arrives by the air route, partly delayed by the slightly longer route.

It is particularly effective if a multi-gun salute such as for "The Queen's Birthday" is being fired. Compression and shear waves[ edit ] Pressure-pulse or compression-type wave longitudinal wave confined to a plane.

Why does sound wave travel faster in a denser medium whereas light travels slower? Shawn Tee Answer Sound is a mechanical wave and travels by compression and rarefaction of the medium.

Its velocity in an elastic medium is proportional to the square root of Tension in the medium.

### Speed of Sound - Sound | HowStuffWorks

A higher density leads to more elasticity in the medium and hence the ease by which compression and rarefaction can take place. This way the velocity of sound increases by increase in density. Light on the other hand is a transverse electromagnetic wave. It does not depend on the elastic property of the medium in which it travels. Its velocity in a medium is determined by the electromagnetic e. Effective path length on the other hand is increased by an increase in the density and hence it leads to higher refractive index and lower velocity.

This may indeed get into complex subject matter, thus I will first give a brief answer followed by explanations. This is why there can be no sound in outer space since it is a vacuum i.