The massive security operation surrounding Barack Obama's inauguration showed that he will be the most protected president in the history of the United States. Photo: REUTERS.
The physics of a tsunami. Tsunamis can have wavelengths ranging from 10 to 500 km and wave periods of up to an hour. As a result of their long wavelengths, tsunamis act as shallow-water waves. A wave becomes a shallow-water wave when the wavelength is very large compared to the water depth. where g is the acceleration due to gravity (= 9.8 m/s2) and H is the depth of water.
All types of waves, including tsunamis, have a wavelength, a wave height, an amplitude, a frequency or period, and a velocity. Wavelength is defined as the distance between two identical points on a wave (i.e. between wave crests or wave troughs).Normal ocean waves have wavelengths of about 100 meters. Wave velocity is the speed of the wave. 2  Velocities of normal ocean waves are about 90 km/hr while tsunamis have velocities up to 950 km/hr (about as fast as jet airplanes), and thus move much more rapidly across ocean basins. 3  The velocity of any wave is equal to the wavelength divided by the wave period.