Science Questions

Why are there two or three waves in a tsunami instead of one? Richard in Colchester

It's essentially the same principle as if you get a cube of sugar and drop it in your cup of tea. It sets up a disturbance in the water surface and it doesn't reach equilibrium again immediately, so you get a lot of oscillations instead of just one. This gives you more than just one wave. They all add together.

January 2006