Search results
Results From The WOW.Com Content Network
The ocean-like quality of seashell resonance is due in part to the similarity between airflow and ocean movement sounds. The association of seashells with the ocean likely plays a further role. Resonators attenuate or emphasize some ambient noise frequencies in the environment, including airflow within the resonator and sound originating from ...
In effect, it is filtering out all frequencies other than its resonance. Acoustic resonance is an important consideration for instrument builders, as most acoustic instruments use resonators, such as the strings and body of a violin, the length of tube in a flute, and the shape of a drum membrane. Acoustic resonance is also important for hearing.
Additionally, a submarine may employ a tactic that prevent sounds from reaching a listener at a particular ocean depth. Operating below the depth of the sound channel axis , where the speed of sound in water is the lowest, a submarine can prevent detection by surface ships, unless these ships use equipment like a towed array and/or an ...
Away from resonance this can reduce tidal energy moving onto the shelf. However near a resonant frequency the phase relationship, between the waves on the shelf and in the deep ocean, can have the effect of drawing energy onto the shelf. The increased speed of long waves in the deep ocean means that the tidal wavelength there is of order 10,000 km.
Output of a computer model of underwater acoustic propagation in a simplified ocean environment. A seafloor map produced by multibeam sonar. Underwater acoustics (also known as hydroacoustics) is the study of the propagation of sound in water and the interaction of the mechanical waves that constitute sound with the water, its contents and its boundaries.
Acoustic resonance technology (ART) is an acoustic inspection technology developed by Det Norske Veritas over the past 20 years. ART exploits the phenomenon of half-wave resonance, whereby a suitably excited resonant target (such as a pipeline wall) exhibits longitudinal resonances at certain frequencies characteristic of the target's thickness.
This is an example of an equation that holds off shell, since it is true for any fields configuration regardless of whether it respects the equations of motion (in this case, the Euler–Lagrange equation given above). However, we can derive an on shell equation by simply substituting the Euler–Lagrange equation:
At the same time, but independently from Miles, Owen M. Phillips [10] (1957) developed his theory for the generation of waves based on the resonance between a fluctuating pressure field and surface waves. The main idea behind Phillips' theory is that this resonance mechanism causes the waves to grow when the length of the waves matches the ...