In what way can water cause mechanical weathering?

Question

i really need help thanks!!!

Answer 1

To elaborate upon YT's answer, in rivers water actually moves rocks and boulders, causing them to collide with each other.  It is the collision that breaks the rocks apart.

Also, water that seeps into cracks in rocks can freeze and "wedge" the rock apart.  This process is called frost wedging.

Incidentally, I've done a little geological research in Canada and have camped in remnant glacial cirques.  You have to be aware of where you place your tent because it is common for frost wedging to cause several boulders per day to come rolling to the cirque floor.  This is most definitely an example of mechanical weathering by water.

Answer 2

Melting and freezing of H20 in fissures expanding and contracting causes allot of mechanical weathering.

Answer 3

It hits/runs over rocks, sand etc. and wears them away.