group velocity
Quick Summary
In physics, group velocity refers to the speed at which a specific characteristic of a composite wave train advances through a medium. This is distinct from phase velocity, which is the speed of a wave's motion determined by its wavelength and frequency.12
Dispersion occurs when waves travel at different velocities depending on their wavelengths. For instance, in deep water, ocean waves move at speeds related to the square root of their wavelengths. In such cases, the group velocity, which represents the speed of wave energy propagation, can differ from the phase velocity. For deep-water waves, the group velocity is half the phase speed.34
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wavePhysical characteristics of surface waves…with the wave, termed the group velocity. For nondispersive long waves the two are equal, whereas for surface gravity waves in deep water the group velocity is only half the phase speed. Thus, in a train of waves spreading out over a pond after a sudden disturbance at a point,…
Read More…with the wave, termed the group velocity. For nondispersive long waves the two are equal, whereas for surface gravity waves in deep water the group velocity is only half the phase speed. Thus, in a train of waves spreading out over a pond after a sudden disturbance at a point,…
Read More- waveWind waves and swell
In the physical sense, group velocity is the velocity of propagation of wave energy. From the dynamics of the waves, it follows that the wave energy per unit area of the sea surface is proportional to the square of the wave height, except for the very last stage of…
Read MoreIn the physical sense, group velocity is the velocity of propagation of wave energy. From the dynamics of the waves, it follows that the wave energy per unit area of the sea surface is proportional to the square of the wave height, except for the very last stage of…
Read More