Why do waves at the beach come in sets?
In: Physics
Short answer its due to Swell.
Long answer, the friction of the wind on the water cause waves and Swell is the very big rolling waves that form over a long period of time out at sea. Then small waves form on swell.
The small waves on the crests of the swell (top of the waves) are given more energy by the wind and the small waves in the troughs of the swell (bottom of the wave) are given less.
So when the waves and swell reaches land, the swell dies out as energy is lost to the friction of water and the sea bed. The weak waves with less energy die out and your left with the strong ones (the set of waves).
Let me know if your unclear about any of it.
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