passage: Abrasion is another type of weathering .
  Like ice wedging , it is a form of mechanical weathering .
  Like ice wedging , abrasion does not change the rock into another type of rock .
  With abrasion , one rock or piece of sediment bumps against another rock .
  Rocks do nt normally roll around on their own , so why do they move ?
  There are a couple of reasons a rock may move .
  Gravity can cause rocks to move .
  They may roll downhill or fall off a cliff .
  As they roll down a hill , they bump into each other .
  Maybe a moving rock hits a rock that is not moving at the bottom of the hill .
  Moving water causes rocks and sediment to move .
  Rocks are bounced along the bottom and bump against one another .
  As they collide , they begin to chip away at each other .
  Angular rocks become more rounded with each collision .
  Strong winds cause abrasion .
  The wind carries sediment .
  This sediment is thrown against other rocky surfaces by the wind .
  It is like sand - blasting a rock .
query_and_answer: What is sediment thrown against other rocky surfaces similar to ? || Like waters move
evidences: This sediment is thrown against other rocky surfaces by the wind . It is like sand - blasting a rock .