7.2 Erosion and Deposition M/C

Which is the best evidence that erosion has occurred?

• a large number of fossils embedded in limestone

• a soil rich in lime on top of a limestone bedrock

• sediments found in a sandbar of a river

• a layer of basalt found on the floor of the ocean

For which movement of earth materials is gravity not the main force?

• snow tumbling in an avalanche

• moisture evaporating from an ocean

• boulders carried by a glacier

• sediments flowing in a river

Which sediment is the largest that could be carried by a stream flowing at a velocity of 100 cm/sec?

• sand

• cobbles

• silt

• pebbles

What can a stream flowing at a velocity of 100 cm/sec can transport?

• silt, sand, and pebbles, but not cobbles

• silt, but not sand, pebbles, or cobbles

• silt, sand, pebbles, and cobbles

• silt and sand, but not pebbles or cobbles

A glass sphere and a lead sphere have the same volume. Each sphere is dropped into a container of water. Which statement best explains why the lead sphere settles faster?

• The lead sphere has a higher density.

• The lead sphere takes up less space

• The glass sphere has more surface area.

• The glass sphere has a smoother surface.

Which rock particles will remain suspended in water for the longest time?

• pebbles

• silt

• clay

• sand

Compared to a low-density spherical particle, a high-density spherical particle of the same size will sink through water

• more rapidly

• more slowly

• at the same rate

In this experiment, the water velocity could be increased by

• decreasing the slope of the rain gutter

• increasing the amount of water from the faucet

• lowering the flexible hose

• widening the rain gutter

What is the relationship between the water velocity and the rate of erosion?

• If the water velocity decreases, the rate of erosion increases.

• If the water velocity increases, the rate of erosion increases.

• If the water velocity remains constant, the rate of erosion decreases.

• If the water velocity remains constant, the rate of erosion increases.

.By adding more textbooks underneath the rail gutter, what happens to velocity?

• increases

• decreases

• remains the same