There are a lot of answers to that. Things fall in the water, boats, sealife, the wind, underwater volcanic activity, earthquakes. But I would think the moon would be the biggest cause, since its gravity makes the tides pull the ocean.
A tsunami
It is a tsunami
waves get slower and higher then they break
Yes, an ocean wave is a mechanical wave, since the water is the medium of the wave.
The force of friction between the ocean wave and the sea floor causes the wave to slow down as it nears the shore. This frictional force results in the wave increasing in height and eventually breaking as it reaches shallow water.
The force that acts on an ocean wave as it nears the shore is called shoaling. Shoaling is the process where the wave interacts with the seafloor, causing the wave to slow down and increase in height. This is what causes waves to break as they approach the shore.
When a wave passes through the ocean it may make a wave.
Tsumamis are often caused by undersea earthquakes. The earthquake makes the ocean floor move, which causes the tsunami-wave.
Waves out in the ocean don't break because they are in deep water, waves break when they reach shallower water and so the bottom of the wave catches on the bottom and causes a bit of friction which slows the wave down and cause it to fall over itself, which is breaking
A sound wave
Friction between the ocean floor and the water can slow down the wave at the bottom, causing the wave to decrease in height and change direction as it approaches shallower water. This can result in the wave breaking as it reaches the shore.
Tsunamis are usually caused by under-sea earthquakes. The shift in the ocean floor moves vast amounts of water, causing a wave. As the wave nears land, the gradual slope of the coastline causes the front of the wave to slow down, while the back of the wave continues at the the same speed. This causes the wave to 'rear up' to great height.