: why do the waves at beaches end at a certain point?



In: 0

What point are you talking about?

On the beach they end because the depth of water gets too shallow for them to continue building.

On the ocean side they don’t end. They continue all throughout the ocean.

Think of it as a bath tub, if you filled it up to the brim, and pushed the water towards the edge (let’s also assume the top of your bathtub is at floor level)

It’s makes a wave that continues across the water all the way until the edge, once it hits the edge, it immediately starts to lose water, since now it’s going all over the floor instead of running over the water

Same thing with a beach, the waves are rolling onto the ground and there is no water underneath them for them to continue pushing, so they go as far as there momentum allows and after that they simply just don’t have anymore water to pull with on the beach

The energy of the wave exerts itself, pushing the water as far up to the beach as it can before gravity counteracts it and pulls the water back into the ocean. It’s the same reason that if you roll a ball up a slope it will only go as far as the energy you put into rolling it before gravity pulls it back down the slope.

TL;DR- Gravity.