1. What is the relationship between permeability and viscosity of water?
a) Directly proportional
b) Inversely proportional
c) Both are equal
d) None of the mentioned
Explanation: From Poiseuille’s law, K=Ds2 γw /ɳ
It is found that permeability is directly proportional to the unit weight of water and inversely proportional to its viscosity.
2. What is the effect of adsorbed water on the permeability of soil?
a) Structural arrangement is varied
b) Reduced degree of saturation
c) Size of the particles is diminished
d) Reduces the pore size
Explanation: The adsorbed water surrounding the fine soil particles is not free to move, and reduces the effective pore space available for the passage of water.
3. What is the approximate value, which can be taken as void ratio occupied by adsorbed water?
a) 1
b) 0
c) 0.1
d) 10
Explanation: According to approximation value after casagrande, 0.1 may be taken as the void ratio occupied by adsorbed water.
4. The effect of structural disturbance is on permeability is more in _____________
a) Fine-grained soil
b) Coarse grained soil
c) Clay soil
d) All of the mentioned
Explanation: The effect of structural disturbance on permeability is much pronounced in fine-grained soil than any other.
5. The structural arrangement of soil Particle vary depending upon ______________
a) Method of deposition and Compacting the soil mass
b) Degree of saturation
c) None of the mentioned
d) All of the mentioned
Explanation: The structural arrangement of the particle may vary, at the same void ratio, depending upon the method of deposition or compacting the soil mass.
6. How do degree of saturation effect permeability of soil?
a) By reducing the pore size
b) By entrapping air in the voids
c) Not allowing soil particles to move freely
d) By changing the void ratio
Explanation: By entrapping the air in the voids present in the soil, the permeability is greatly reduced, thus reducing the degree of saturation.
7. Falling head permeability test can be used for ___________
a) Coarse-grained soil
b) Less permeable soil
c) Clayey soil
d) All of the mentioned
Explanation: Falling head test is used for relatively less permeable soils where the discharge is small.
8. Which of the following formula is used in Falling head permeability test?
a) Jacky’s formula
b) Louden’s formula
c) Darcy’s law
d) Kozney’s formula
Explanation: In falling head permeability test, Darcy’s law is used from which the rate of flow q, can be used
q = K i A.
9. In falling head permeability test apparatus, the water head at any time instant is equal to ___________
a) Difference in the water level
b) Cross-sectional area of pipe
c) Height of permeameter
d) None of the mentioned
Explanation: The head h1 and h2 at any time instant t is equal to the difference in the water level in the stand pipe and the bottom tank.
10. In constant permeability test, the length of specimen is measured by ___________
a) Calculating the difference in water level
b) Using Piezometric tube
c) Using measuring scale
d) None of the mentioned
Explanation: In a constant head test, the length of the sample is measured by inserting piezometric tubes on top and bottom.