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.
Tsunamis range in size from inches to over a hundred feet. In deep water (greater than 600 feet/180 meters), tsunamis are rarely over 3 feet (1 meter) and will not be noticed by ships due to their long period (time between crests). As tsunamis propagate into shallow water, the wave height can increase by over 10 times.Tsunami heights vary greatly along a coast.