Why are pebbles on the beach so smooth?

Question

They never have sharp edges unless broken, so why are these tiny rocks so smooth?

Answer 1

They're worn down that way over time. When they're at the bottom of the water, they bump into each other and the water sometimes will slide them against one another and it gives them that smooth finish. Then the tide sweeps them onshore. When the tide comes in again, it takes some of the pebbles back and the whole process goes on over and over.

That's all it is...erosion. =)

Answer 2

Smooth Pebbles

Answer 3

The action of the sea smooths out the sharp edges.

Answer 4

the motion of the water grinds the stones together for hundreds of years wearing down the sharp edges.
You can do the same thing with any stone by buying a toy tumbler in the kid's stores, which turns like a a clothes dryer, filled with rocks.
You just let the tumbler run and the rocks grind down each other - including the one you want to get the sharp edges from.

Answer 5

Attrition, or at least I think that's the right word. The pebbles are caught up in currents and wear against one another due to the action of the sea, breaking off and rounding any sharp edges.

Answer 6

well, it is quite possible that the reason that they are so smooth is that as the waves go up and down the beach, it causes erosion. Similar to the way that a rushing river has soft, smooth rocks. EROSION.

Answer 7

Because the movement of the water, caused by the tides, causes the to rub gently against each other, thus removing the sharp edges.

Answer 8

The water rolling over top the pebbles cause them to move over each other and against the sand~~thus smoothing / polishing them.

Answer 9

Because the movement of the water smooths them. You find smooth rocks in rivers, as well.

Answer 10

The water and sand and the rocks themselves from banging into other rocks have been eroded, chipped away and smoothed over.

physical and chemical erotion.

sand is the net result of the beach side erotion processes