The term octopus may also refer to only those creatures in the genus Octopus.
Our ability to hear sounds provides us with an important mode of perception of our environment.
Sound is transmitted by means of sound waves, much as a pebble thrown into a lake generates waves on the surface of the water.
Certain sounds of nature and music have the power to calm the mind and heal the body.
Acoustics is a branch of physics that studies sound, or more precisely, mechanical waves in gases, liquids, and solids.
Recording devices store sound wave information, such as conversations or musical performances, by translating them into a mechanical or electronic form that can be used to reconstitute the original sound.
Scientists group all such vibratory phenomena under the general category of "sound," even when they lie outside the range of human hearing.
Based on the evolutionary theory of descent with modification, it would be expected that camels once existed in North America but became extinct.
We depend on sound for communication through speech and artistic expression through music.
Humans and many animals use their ears to hear sound, but loud sounds and low-frequency sounds can be perceived by other parts of the body as well, through the sense of touch.
The technology of sonar, based on underwater sound propagation, is useful for detecting icebergs, marine life, and ocean-going vessels.
The speed of sound has been a subject of study since the days of the philosopher Aristotle (384–322 B.C.E.).
The properties of a sound wave depend upon the springiness, or elasticity, of the material that the sound travels through.
The movement of a sound wave is accompanied by the transmission of energy that is spread over the spherical wave front.
Sound is therefore characterized by the properties of waves, such as their frequency, wavelength, period, amplitude, and velocity (or speed).
The matter that supports the transmission of sound is called the medium.
At very high amplitudes, sound waves exhibit nonlinear effects, including shock.
In air at room temperature, the speed of sound is approximately 345 meters per second (ms-1); in water, 1,500 m/s-1; and in a bar of steel, 5,000 m/s-1.
The design of musical instruments requires an understanding of the manner in which sound is created and transmitted, and a knowledge of materials and their acoustical characteristics.
Sound waves are longitudinal waves, meaning that the vibrations (compression and rarefaction of the medium) occur in the direction in which the wave moves.
The telephone, one of the earliest technologies developed for rapid communication, translates sound waves into electrical impulses that are converted back into sound waves at the receiving end.
Modern sound technology is closely intertwined with the electronics industry, which has perfected a multitude of ways to convey and reproduce sound electronically.
Ultrasound (high-frequency sound) is used to generate images of a fetus or a person's internal organs, and to inspect materials for possible flaws.
The Qur’an does not use the word jihad to refer to warfare or fighting; such acts are referred to as qital.
Sounds above 20,000 Hz are classified as ultrasound; sounds below 20 Hz, as infrasound.
Sound can also be used to acquire information about objects at a distance or otherwise hidden from sight.
An amplifier takes a sound of weak amplitude and generates an equivalent one with greater amplitude that can be heard more easily.
Ancient societies constructed amphitheaters designed to carry the sounds of actors' voices to the audience, requiring knowledge of acoustics.
Prolonged exposure to a sound pressure level exceeding 85 dB can permanently damage the ear, sometimes resulting in tinnitus and hearing impairment.
Through the development of technology, sound waves can be converted to electrical signals and radio waves and transmitted almost instantaneously to distant parts of the globe.
The speed of sound in air or a gas increases with the temperature of the gas.
A cannon, for example, will be seen to flash and smoke before the sound of the explosive powder reaches an observer.
The mathematical equation to calculate the sound pressure level (Lp) is as follows.
The speed at which sound travels depends on the medium through which the sound waves pass, and is often quoted as a fundamental property of the material.
Sound levels in excess of 130 dB are considered above of what the human ear can withstand and may result in serious pain and permanent damage.
The cause of sound is vibratory movement from a disturbance, communicated to the ear through a medium such as air.
Certain naturally occurring and artificially produced sounds can soothe or stimulate the mind and help heal the body.
In air, a sound wave is a disturbance that creates a region of high pressure (compression) followed by one of low pressure (rarefaction).
The amplitude of a sound wave is specified in terms of its pressure, measured in pascal (Pa) units.
They have a small sac in their throats that vibrates the air as they slowly let it out. The sounds that frogs make are not what you'd expect. Did you know that there are frogs that chirp? Others can whistle, croak, ribbit, peep, cluck, bark and grunt.
When threatened, or when fighting an enemy, the leopard will hiss, spit, growl, snarl, and make rasping yowls. Leopards have also been known to purr during feeding, and females purr and meow, much as domestic cats do, but normally only between mother and cubs.Jan 6, 2013
Longitudinal Waves and Guitar Strings. A sound wave is produced by a vibrating object. As a guitar string vibrates, it sets surrounding air molecules into vibrational motion. The frequency at which these air molecules vibrate is equal to the frequency of vibration of the guitar string.
The American Crow is not known for the beauty of its song, a series of loud caws. You may also hear crows making a “subsong”: a mixture of hoarse or grating coos, caws, rattles, and clicks. These are arranged in sequences that can be many minutes long, given quietly and with a rambling, improvised quality.