What is a Tsunami?
Tsunamis are formed as the displaced water mass moves under the influence of gravity and radiates across the ocean like ripples on a pond. They are sometimes called "seismic sea waves." They are normally formed because of earthquakes under the sea.
Tsunami Video for Physics
The Physics behind a Tsunami
When tectonic plates come in contact with each other, it creates a vibration, and vibrations create waves. In this case, mechanical waves are created in the water from this vibration. As the wave travels through deep water, it carries much kinetic energy; it has a lot of speed. Once it gets to shallow waters, the friction of the land below the water slows the wave down. Kinetic energy is decreased, but the potential energy skyrockets. This causes the wave's height to increase to enormous heights. The wave then crashes down, heading inland and ruining everything in sight. And it's not over yet... the water is then retracted back into the sea, carrying everything with it that it engulfed on the land.
Sumatra, Indonesia - the worst Tsunami recorded in history
The depth of the earthquake occurred at 30 kilometers. The resulting tsunami was recorded to be 1300 kilometers long, vertically displacing the sea floor by several meters along that length. The tsunami wave reached a height of 50 meters, traveling 5 kilometers in land. Other countries suffered from the destruction, including the US, UK, and Antarctica. About 250,000 people were reported dead from the disaster.