Geotechnical Engineering

Sedimentation Analysis

Question 1
Marks : +2 | -2
Pass Ratio : 100%
The lower limit of particle size allowed in sedimentation analysis is ________
0.0002 mm
0.04 mm
0.074 mm
0.0004 mm
Explanation:
The particle smaller than 0.0002 mm is affected by Brownian movement and stokes law remains no longer valid.
Question 2
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Pass Ratio : 100%
The sedimentation analysis is done with the help of________
Hydrometer and Pipette
Sieve
All of the mentioned
None of the mentioned
Explanation:
Both the hydrometer and pipette method can be used for taking sedimentation analysis.
Question 3
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Pass Ratio : 100%
In the formula, f=105√(300 ɳ/(g-1)Vw), the factor ɳ depends on__________
Pressure
Velocity
Temperature
Specific gravity
Explanation:
Since ɳ=viscosity of water/liquid, it can be affected by temperature.
Question 4
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The time for a particle to settle, of diameter 0.06 through a height of 10 cm is_________
25.8 s
42 m 59 s
3 m 52 s
42.8 s
Explanation:
Based on the time of settlement of particles of various diameters it is found that minimum time of 25.8 s is needed for a particle to settle of diameter 0.006 mm.
Question 5
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The unit weight of water in v=(2/g)r2(Vs-Vw/ɳ) is taken as ________
9.81 kn/m2
98.1 n/m2
0.981 kn/m2
9.81 n/m3
Explanation:
The constant value of unit weight of water/liquid is taken as γw=9.81 kn/m2.
Question 6
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Pass Ratio : 100%
In sedimentation analysis, the soil fraction should be of what micron size, so as to be kept in a liquid medium (water).
75
83
57
70
Explanation:
According to Indian standards the soil fraction is set as 75 microns to be used in a liquid medium.
Question 7
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Viscosity of water/liquid (ɳ) is expressed in ________
KN-s/m3
Ns/m2
KN-s/m2
Ns/m
Explanation:
The viscosity of distilled water in sedimentation analysis is taken as 0.00855 KN-s/m2.
Question 8
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The sedimentation analysis is based on _________ law.
Stoke
Cullman’s
Rankine’s
None of the mentioned
Explanation:
The sedimentation analysis is based on stokes law according to which the velocity at which the grains settles down depend on shape, size, weight of grain.
Question 9
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Pass Ratio : 100%
Which of the following assumptions is wrong, with respect to sedimentation analysis?
The soil particles are spherical
Particle settle independent of other particles do not have any effect on its velocity of settlements
Soil particles has different specific gravity
The walls of jar, in which the suspension is kept do not affect the settlement
Explanation:
In sedimentation analysis, soil particle has average specific gravity.
Question 10
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Pass Ratio : 100%
1 poise is equivalent to _________
0.5 NS/m2
0.1 NS/ m2
10-4 K NS/ m2
0.8 NS/ m2
Explanation:
As,1 poise =1/10 NS/ m2