Soil Science Exam 2 Updated Actual Questions And Correct Answers

SOIL SCIENCE EXAM 2 UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
Question:
1. True or False: Bulk Density and porosity are two soil parameters, which are NOT directly related.
Answer:
False

Question:
2. For bulk density what would most likely represent very sandy soil?
Answer:
1.60 g/cm^3

Question:
3. For soil porosity what would most likely represent very clayey soil?
Answer:
58%

Question:
4. True or False: Soil compaction is caused by reduction in soil porosity
Answer:
True

Question:
5. True or False:Swelling (expansive) soils are not susceptible to compaction.
Answer:
False

Question:
6. At fixed soil moisture and texture, as the axle load increases, the depth of soil compaction _____.
Answer:
also increases

Question:
7. The resistance of soil to penetration with a blunt object is an important indicator of engineering soil
quality because it signifies easiness of soil preparation for construction purposes. This physical
property of soil is called _____.
Answer:
consistancy

Question:
8. In non-cohesive soil which is dominated by frictional forces a very low water content will ______
its bearing strength while a very high water content will ______ its bearing strength while a very high
water content will
Answer:
Decrease, decrease

,Question:
9. The ability of soil to resist deformation or rupturing is an important indicator of engineering soil
quality because it signifies cohesiveness of the soil. This physical property of soil is called _____.
Answer:
bearing strength

Question:
10. The Coefficient of Linear Extensibility, or COLE for short, is an important indicator of this
physical phenomenon. Which is?
Answer:
shrink swell

Question:
11. Soils on slopes become prone to landslide when one of the soil layers becomes liquefied. Soils will
transition from solid to viscous liquids at this water content. Which is known as?
Answer:
liquidity limit (LL)

Question:
12. You have a very light Styrofoam box that you fill with soil. You place the box in the garage and
forget about it for a few months during the summer. The garage is pretty hot and the soil eventually
becomes very dry. You later pick up the box and determine the box and soil weighs about 138 lbs.
Approximately, what is the bulk density of the soil in lbs/ft^3? (Box: l=24 in. w=18 in. h=8 in.)
Answer:
69

Question:
13. A soil core is taken from a field and oven dried. The core radius (r) is 4.5 cm and the height (h) is 6
cm. The weight of the core is 24 grams. The weight of the core and oven dry soil is 389 g. The bulk
density of the soil is _____ g/cm^3. (core vol=Pi× r² ×h)
Answer:
0.96

Question:
14. A vibrating compactor is being used on a coarse textured soil before the cement driveway is
installed. This procedure will _____ the bulk density of the soil.
Answer:
increase

Question:
15. Mean particle density of soil is a ratio between these two parameters. Which are?
Answer:
volume of soil particles and weight of oven dry soil

Question:
16. For bulk density what could most likely represent loamy soil?
Answer:
1.40 g/cm^3

, Question:
17. For soil porosity, what could most likely represent very sandy soil?
Answer:
40%

Question:
18. True or False: Soil compaction is always a bad thing.
Answer:
False

Question:
19. True or False: Sandy soils are more prone to compaction than fine textured soils.
Answer:
False

Question:
20. At fixed soil texture, as the soil moisture content decreases, the depth of soil compaction _____.
Answer:
also decreases

Question:
21. As the clay content of soil increases clods become _____.
Answer:
harder

Question:
22. In order for the cohesive forces to play important role in soil's bearing strength its clay content
needs to be at least ______ percent.
Answer:
15

Question:
23. True or False:With regards to its bearing strength, the cohesive soils become unstable at very low
water content.
Answer:
False

Question:
24. Fine textured soil with very low plasticity index will be dominated by this secondary
phyllosilicate. Which is?
Answer:
kaolinite

Question:
25. Soils with more that 30% of expandable (2:1) clays will have _____ Coefficient of Linear
Extensibility (COLE).