7.3 Erosion

What are the largest particles that a stream can transport when its velocity is 200 centimeters per second?

• silt

• pebbles

• cobbles

• sand

What is the largest particle that can be kept in motion by a stream that has a velocity of 100 centimeters per second?

• pebble

• cobble

• silt

• sand

An observer notes that in a particular part of a stream, the water transports clay, silt, sand, pebbles, and cobbles, but not boulders.

What is the approximate stream velocity?

• 50 cm/s

• 100 cm/s

• 250 cm/s

• 400 cm/s

If a river is flowing at a speed of 50 cm/s, what kind of sediments can it transport?

• silt and sand

• silt, sand, and pebbles

• silt, sand, pebbles, and cobbles

• silt, sand, pebbles, cobbles, and boulders

How are particles of sand and pebbles that are less dense than water carried by a stream?

• by bouncing along the bottom in traction

• by solution in water

• by chemical weathering

• by floating on the surface

Tags

NGSS.MS-PS2-2

Which factor most likely caused the sediment to be sorted in the pattern shown?

• hardness of the surface bedrock

• velocity of the water

• mineral composition of the sediment

• temperature of the water

Tags

NGSS.MS-ESS2-4

Based on the features shown, which erosional agent had the greatest effect on tree growth and the structures that humans have built on this landscape?

• running water

• moving ice

• prevailing wind

• mass movement

What is the minimum rate of flow at which water can usually keep pebbles 1.0 centimeters in diameter moving downstream?

• 50 cm/s

• 100 cm/s

• 150 cm/s

• 200 cm/s

What was the primary force that caused this landslide?

• gravity

• prevailing winds

• moving ice

• stream discharge

Tags

NGSS.MS-ESS2-2

What is the approximate minimum stream velocity needed to keep a particle in motion that has a diameter of 10 centimeters?

• 110 cm/s

• 190 cm/s

• 325 cm/s

• 425 cm/s

Tags

NGSS.MS-PS3-1