[neilep (OP)]

Ok..I know that the moon causes the tides ?....is it then responsible for tides crashing on the sea shore ?

If not what is ?


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[paul.fr]

This question is quite hard (for me anyway) to answer. But i will have a go.
If you think of a wave simply as an energy, and let us say that the wave started out in deep water away from the shore line.

Out in deep water the wave or energy does not have too much in it's path to interact with, so all we see is the top of this energy - the wave, and maybe a bird or something bobbing up and down on it.

Now, as the wave nears the shoreline it may come accross a barrier, thast being a sandy bottom that is at an incline, at some point the amplitude of the wave will be higher than the total depth of the water. the energy will interact with the sandy bottom and the energy will be reflected causing the energy to go in a different direction other than toward the shoreline.

Sort of think of this as a sin wave with nice peaks and troughs, it starts out in a nice straight line, from deep water to the shallow shoreline. As it nears the shore, the wave with it's peaks and troughs move upwards. This is what you see as a wave.

The energy / wave at the surface is pushing towrds the shoreline, yet the energy on the sea bottom is pushing back out to sea. Both of these forces meet and cause what you see as a wave, curl or break.

This is also why, when you see a duck or bird bobbing on the water it appears stationary. One energy pushing one way and another the other way.

It is all very complicated and what i have written may not actually make too much sense.