Profile
Settings
Refer your friends
Sign out
Sound Waves
Sound is a kind of vibration or disturbance that transmits through a medium, such as solid, liquid or gas, to reach its destination. Biologically it is received by the ear and is perceived by the brain. The normal frequency of the sound heard by the human ear is between 20Hz to 20 kHz. Any sound wave which is above 20kHz is called ultrasonic sound, which is not heard by humans but by Bats. Less than 20Hz sound waves are termed infrared.
Properties of sound waves:
There are two types of sound waves depending on the way the sound waves propagate:
- Longitudinal
- Transverse
Longitudinal Waves:
The sound spreads through air or different mediums as a longitudinal wave, in which the mechanical vibration establishes the wave happens along the same path as the transmitting wave. A longitudinal wave can be made in a curled spring by pressing a few of the turns together to frame a pressure and afterwards delivering them, permitting the pressure to venture to every part of the length of the spring. Air can be seen as being made from layers like such curls, with a sound wave engendering as layers of air “push” and “pull” at each other similar to the pressure dropping down the spring.
A sound wave along these lines consists of exchanging compressions and rarefactions, or locales of high tension and low strain, moving at a specific speed. Put another way; it comprises an intermittent (that is, wavering or vibrating) variety of strain happening around the harmony pressure winning at a specific overall setting. Balance pressure and the sinusoidal varieties brought about by the entry of an unadulterated sound wave.
Transverse Waves:
In this type of wave, for example, the wave created in an extended rope when one end is squirmed to and fro, the movement that comprises the wave is opposite, or cross over, to the heading (along the rope) where the wave is moving. A significant group of cross-over waves is created by electromagnetic sources, for example, light or radio, in which the electric and attractive fields established the wave sway opposite to the course of spread.
The Speed of Sound in Different medium
The speed of sound is defined as how much the sound wave has travelled per unit of time as it travels through a medium. It highly depends on the temperature of the medium and the nature of the medium. For solids, the speed of transverse waves depends on the shear deformation due to shear stress as well as on the density of the medium. For longitudinal waves, the above two conditions are the same but also depend on their compressibility. For fluids, the medium’s compressibility and the medium’s density are necessary. In the case of gases, only temperature and their molecular structure are required.
The relation between the speed of sound, its frequency and wavelength is
v(velocity) = f(frequency) * λ(wavelength)
Speed of sound in solids, liquids, and gases
In solid structure, as the particles are very closely placed to each other and there is less movement of the particles, the propagation of the vibration through it is faster, and hence the speed of sound is the fastest through the solids; that is why it takes milliseconds to reach your ears when someone from the other room calls you. In liquids, the particles/ molecules are a bit loosely packed, and hence the propagation is a bit slow, so the speed of sound through liquid is a bit slow. And it is the slowest in gases as the molecules in the gases are very loosely packed.
Hence, the speed of sound in solids is 6000 m/s.
In liquid at 20 degrees Celsius, the speed of sound is 1481 m/s.
The speed of sound in air is 343 m/s at 20 degrees Celsius, and at 0 degrees Celsius, it is 331m/s.
Conclusion:
You see the blaze of a blast a long time before you hear its sound and potentially feel the pressure wave, inferring both that sound goes at a limited speed and that it is a lot slower than light. It depends on so many factors and can be applied to our day-to-day life easily. We hear songs every day or people talking to each other every day, even from different places. I expect that I could be of a little assistance and help you understand the topic a little bit.
