The process that breaks down rocks and other materials on Earth's surface is called

• weathering
• erosion
• soil conservation
• decomposition

What is mechanical weathering?

• Process through which rocks are physically broken into smaller pieces.
• Rocks are broken down through chemical changes.
• Rocks are worn away from acid in plant roots.
• Rocks broken down by machinery.

How does freezing water cause the weathering of rocks?  The freezing water—

• keeps the rocks in place
• makes the rocks last longer
• expands cracks and breaks rocks
• causes rocks to fall in landslides

How does wind abrasion work?

• Sediment is blown off a surface from wind.
• Wind-blown sediment strikes a surface.
• Wind blows large chunks of rock off a surface.
• Sediment falls off of a surface on its own.

The diagrams  shows a natural process that weathers rock.
 Which statement best explains why this process results in weathering?

• frozen water acts as a solute
• water expands when it freezes
• the mass of water increases when it freezes
• frozen water dissolves most types of rock

All of the following are causes of physical weathering except...

• plant growth
• wind
• acid rain
• running water

Tree roots cause

• physical weathering.
• chemical weathering.
• both chemical and physical weathering.
• neither chemical or physical weathering.

Physical and chemical weathering both

• change rocks into new materials.
• dissolve rocks.
• break rocks into smaller pieces.
• require exposure to air.

Weeds growing into the cracks in a sidewalk and the sidewalk begins to crumble is an example of:

• mechanical weathering
• chemical weathering

Picture A is a mountain in the Sierra Nevada. Picture B shows only the west ridge of the mountain range.  What is the most likely reason for the shape of picture B?

• It was hit by a volcanoe
• Chemical weathering
• mechanical weathering
• it was caused by an earthquake