Why Do Feet Sink in Sand on Beaches?

[abhiroop_k]

standing on a beach!

why do one's feet get absorbed into sand on a beach when one stands in the water??

 

[JaredJames]

why do one's feet get absorbed into sand on a beach when one stands in the water??

The basic answer is that the water lowers the density.

Dry sand packs together fairly tightly and when you stand on it there's little give - you may sink a little bit in loose sand on the top.

Think of the water as adding spacing between the particles of sand, so when you step on it they are free to move about.

Because of this the sand and water mix is less dense than your body you begin to sink.

It's one of the causes of quicksand.

A slightly more interesting phenomenon for you to look up is liquefaction: http://en.wikipedia.org/wiki/Soil_liquefaction

 

[abhiroop_k]

thanks..