Search results
Results From The WOW.Com Content Network
In acoustics, the sound speed gradient is the rate of change of the speed of sound with distance, for example with depth in the ocean, [1] or height in the Earth's atmosphere. A sound speed gradient leads to refraction of sound wavefronts in the direction of lower sound speed, causing the sound rays to follow a curved path.
The speed of sound is the distance travelled per unit of time by a sound wave as it propagates through an elastic medium. More simply, the speed of sound is how fast vibrations travel. At 20 °C (68 °F), the speed of sound in air, is about 343 m/s (1,125 ft/s; 1,235 km/h; 767 mph; 667 kn), or 1 km in 2.91 s or one mile in 4.69 s.
Figure 1. Table 1's data in graphical format. Although given as a function of depth [note 1], the speed of sound in the ocean does not depend solely on depth.Rather, for a given depth, the speed of sound depends on the temperature at that depth, the depth itself, and the salinity at that depth, in that order.
The speed of sound (i.e., the longitudinal motion of wavefronts) is related to frequency and wavelength of a wave by =.. This is different from the particle velocity , which refers to the motion of molecules in the medium due to the sound, and relates to the plane wave pressure to the fluid density and sound speed by =.
The speed of sound in any chemical element in the fluid phase has one temperature-dependent value. In the solid phase, different types of sound wave may be propagated, each with its own speed: among these types of wave are longitudinal (as in fluids), transversal, and (along a surface or plate) extensional. [1]
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
where is the Laplace operator, is the acoustic pressure (the local deviation from the ambient pressure), and is the speed of sound. A similar looking wave equation but for the vector field particle velocity is given by
The SOFAR channel (short for sound fixing and ranging channel), or deep sound channel (DSC), [1] is a horizontal layer of water in the ocean at which depth the speed of sound is at its minimum. The SOFAR channel acts as a waveguide for sound, and low frequency sound waves within the channel may travel thousands of miles before dissipating.