In determining the speed of sound in a given material, the material's stiffness and density tend to work against each other. While solids usually have a higher speed of sound than liquids because solids are stiffer than liquids, this generalization is not always true because density also plays a role.
While water is denser than air, its stiffness is enough greater than air to compensate for the high density and make the speed of sound greater in water. But the fact that sound travels faster in water than in air just brings up the next question: Why is it harder to talk to someone underwater than in air?
The answer is that sound couples poorly from air to water. When you talk, you do so by emitting air and then sending compression waves through this air. Your lungs provide the burst of air, and your vibrating vocal cords and mouth imprint the appropriate sound waveform on the air. In order for someone underwater to hear you, the sound waves have to go from the air in your mouth into the water surrounding you. They need a medium to travel through.
They cause particles of the medium to vibrate parallel to the direction of wave travel. The vibrations can travel through solids, liquids or gases. The speed of sound depends on the medium through which it is travelling. When gases heat up, their molecules move much more quickly. This increased vibration transmits the sound more quickly than it would in colder, but more static, air.
Understanding the way sound travels through different mediums is an important part of how we at Soundproof Cow develop our sound blocking and sound absorbing materials. To learn more about how Soundproof Cow products can block unwanted sound and absorb harsh noises, visit SoundproofCow.
Get a Free Acoustic Analysis. Share This Post. A sound wave is a pressure disturbance that travels through a medium by means of particle-to-particle interaction. As one particle becomes disturbed, it exerts a force on the next adjacent particle, thus disturbing that particle from rest and transporting the energy through the medium. Like any wave, the speed of a sound wave refers to how fast the disturbance is passed from particle to particle.
While frequency refers to the number of vibrations that an individual particle makes per unit of time, speed refers to the distance that the disturbance travels per unit of time.
Always be cautious to distinguish between the two often-confused quantities of speed how fast In equation form, this is. The faster a sound wave travels, the more distance it will cover in the same period of time.
Faster waves cover more distance in the same period of time. The speed of any wave depends upon the properties of the medium through which the wave is traveling. Typically there are two essential types of properties that affect wave speed - inertial properties and elastic properties. Elastic properties are those properties related to the tendency of a material to maintain its shape and not deform whenever a force or stress is applied to it.
A material such as steel will experience a very small deformation of shape and dimension when a stress is applied to it. Steel is a rigid material with a high elasticity. On the other hand, a material such as a rubber band is highly flexible; when a force is applied to stretch the rubber band, it deforms or changes its shape readily.
A small stress on the rubber band causes a large deformation. Steel is considered to be a stiff or rigid material, whereas a rubber band is considered a flexible material.
When a force is applied in an attempt to stretch or deform the material, its strong particle interactions prevent this deformation and help the material maintain its shape. Rigid materials such as steel are considered to have a high elasticity. Elastic modulus is the technical term. The phase of matter has a tremendous impact upon the elastic properties of the medium. In general, solids have the strongest interactions between particles, followed by liquids and then gases.
For this reason, longitudinal sound waves travel faster in solids than they do in liquids than they do in gases. Even though the inertial factor may favor gases, the elastic factor has a greater influence on the speed v of a wave, thus yielding this general pattern:.
Inertial properties are those properties related to the material's tendency to be sluggish to changes in its state of motion. The density of a medium is an example of an inertial property. The greater the inertia i.
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