Quiz: Civil Engineering 25 AUG 2020

Quiz: Civil Engineering
Exam: UPPSC-AE
Topic: Miscellaneous

Each question carries 1 mark
Negative marking: 1/3 mark
Time: 10 Minutes

Q1. For laminar flow in a pipe carrying a given discharge, the height of surface roughness is doubled, In such a case the Darcy-Weisback friction factor will
(a) remain unchanged
(b) be halved
(c) be doubled
(d) increase four hold

Q2. The irrigation works constructed for regulating the supply of irrigation water is called as
(a) Regulators
(b) Escapes
(c) Falls
(d) Canal outlet and modulus

Q3. The depth of water below the spillway and after hydraulic jump are 1 m and 6m respectively. The head loss will be ……………
(a) 174 m
(b) 5.2 m
(c) 1.7 m
(d) None of these

Q4. The absolute minimum radius of curve for safe operation, for a speed of 100 kmph is:
(a) 260 m
(b) 440 m
(c) 360 m
(d) 320 m

Q5. Which one of the following expression gives intermediate sight distance as per I.R.C. standards? (SSD: Stopping sight distance; OSD: Overtaking sight distance)
(a) 2OSD
(b) ((SSD+OSD))/2
(c) 2SSD
(d) ((OSD-SSD)/2)

Q6. Consider the following statements:
Reciprocal levelling eliminates the effect of
1. errors due to atmospheric refraction
2. errors due to earth’s curvature
3. errors due to line of collimation
4. mistake in taking levelling staff readings
Which of these statements are correct?
(a) 2, 3 and 4
(b) 1, 3 and 4
(c) 1, 2 and 3
(d) 1, 2 and 4

Q7. The various treatment process in a water treatment plant are listed below:
1. Chlorination
2. Filtration
3. Flocculation
4. Coagulation
5. Sedimentation
The correct sequence of these processes in water treatment is
(a) 1, 2, 3, 4, 5
(b) 4, 3, 5, 2, 1
(c) 1, 2, 5, 3, 4
(d) 4, 5, 3, 1, 2

Q8. The maximum safe permissible limit of sulphates in domestic water supply is
(a) 200 mg/l
(b) 600 mg/l
(c) 100 mg/l
(d) 500 mg/l

Q9. Consider the following statements:
high early strength of cement is obtained as a result of
1. Decreasing the lime content
2. Burring at higher temperature
3. Increasing the quantity of Gypsum
4. fine grinding
Which of the above statements are correct?
(a) 1 and 2
(b) 2 and 4
(c) 2 and 3
(d) 1 and 4

Q10. If K is coefficient of permeability, m_v is coefficient of volumetric change and γ_w is unit weight of water, then coefficient of consolidation will be
(a) C_v=K/(m_v×γ_w )
(b) C_v=(m_v×γ_w)/K
(c) C_v=(K×γ_w)/m_v
(d) None of these

SOLUTIONS

S1. Ans.(a)
Sol. laminar flow is governed by Reynolds number only and the Darcy-Weisbach friction factor in case of pipe flow is f=64/Re, Hence, the flow will remain unchanged.

S2. Ans.(a)
Sol. The irrigation works constructed for regulating the supply of irrigation water is called as Regulators. The main purpose of the regulators is to regulate the discharge depth or velocity in canal.

S3. Ans. (b)
Sol. y_1 = 1 m.
y_2 = 6 m.
Head loss (h_L) = ((y_2-y_1)³)/(4y_1 y_2 )
= ((6-1)³)/(4 × 6 ×1)

h_L = 5.20 m

S4. Ans.(c)
Sol. Given,
Minimum design speed V_min = 100 kmph
e_max = 0.07, f = 0.15 (Normally)
Absolute minimum radius (R_Absolute)→
R_Absolute=V^2/127(e+f)
=(100)^2/127(0.07+0.15)
= 357.9 m ≃ 360 m

S5. Ans.(c)
Sol. As per IRC 66 : 1976–
The intermediate sight distance = 2 × SSD
SSD = Stopping sight distance

S6. Ans.(c)
Sol. Reciprocal levelling is used to determine the correct difference of elevations of two points. It eliminates the error due to curvature of earth, atmospheric refraction, and collimation error.

S7. Ans.(b)
Sol. The correct sequence of processes in water treatment plant is follows as–
Coagulation → flocculation → sedimentation → filtration → Chlorination

S8. Ans.(a)
Sol. The maximum safe-limits in domestic water supply are:
Chloride ≤ 250 mg/l
Nitrates ≤ 45 mg/l
Sulphates ≤ 200 mg/l
Fluorides ≤ 1.5 mg/l

S9. Ans.(b)
Sol. Burning at higher temperature increases tricalcium silicate, hence leads to high early strength and finer the cement more is the rate of hydration which results in development of early strength.

S10. Ans.(a)
Sol. ▭(C_v=K/(m_v r_ω))
C_v→ coefficient of consolidation
K → permeability
m_v→ coefficient of volume compressibility
r_ω→ unit weight of water