Junior Engineer • 2020 • Technical Paper-II
If T is time of concentration (in m), L is the maximum length of the flow (in m) & S is the average slope of the area (in m/m) then, Empirical formula for estimating the time of concentration is
A)
T = 0.0195 L^0.77 S^-0.385
B)
T = 0.0190 L^0.77 S^-0.385
C)
T = 0.0195 L^0.77 S^-0.380
D)
T = 0.0195 L^0.70 S^-0.385
The standard empirical formula for time of concentration used in hydrology is the Kirpich-type relation: T = 0.0195 L^0.77 S^-0.385, where L is the maximum flow length and S is the average slope. Among the given choices, option (a) matches this formula exactly. The other options have an incorrect coefficient or incorrect exponent values.
Junior Engineer • 2020 • Technical Paper-II
Bored tube wells in rocky consolidated formations are usually drilled by –
A)
Cable method of drilling
B)
Rotary drilling rigs
C)
Percussion drilling rigs
D)
Down the hole hammer (DTH) rigs
In rocky consolidated formations, bored tube wells are commonly drilled using DTH rigs because they are effective in hard rock and can penetrate fractured, consolidated strata efficiently. Cable tool and percussion methods are older and slower, while rotary drilling is more suitable for softer or unconsolidated formations. Hence, the correct answer is DTH rigs.
Junior Engineer • 2020 • Technical Paper-II
________ is also called ________.
A)
Isohyetal method, arithmetic average method
B)
Isohyetal method, weighted average method
C)
Thiessen polygon method, Arithmetic average method
D)
Thiessen polygon method, Weighted mean method
The Thiessen polygon method estimates areal rainfall by assigning weights to rain gauges based on the area of influence of each gauge. Because the final rainfall is computed as a weighted average, it is also called the weighted mean method. The isohyetal method, on the other hand, is a separate area-weighted technique based on contours of equal rainfall, not the arithmetic average method.
Junior Engineer • 2020 • Technical Paper-II
According to ________ percolation of water through soil for laminar flow conditions in a saturated soil, the rate of flow, or the discharge per unit time is proportional to the hydraulic gradient.
A)
Kenedy’s theory
B)
Darcy’s law
C)
Dupuit’s theory
D)
None of these
Darcy’s law states that for laminar flow through saturated soil, the discharge is proportional to the hydraulic gradient. This exactly matches the statement about percolation of water through soil under laminar flow conditions. Kenedy’s theory and Dupuit’s theory are related to other hydraulic/groundwater concepts, not this basic flow law.
Junior Engineer • 2020 • Technical Paper-II
Central Board of Irrigation & Power has suggested that Pack Aquifer ratio (PA ratio) should be between ________ for uniform aquifers having Cu 2.0.
A)
9 and 12.5
B)
12 and 15.5
C)
14 and 16.5
D)
15 and 18.5
For uniform aquifers with coefficient of uniformity Cu ≤ 2.0, the Central Board of Irrigation & Power recommends the Pack Aquifer ratio (PA ratio) to be in the range of 9 to 12.5. This is the standard design guideline used for selecting suitable pack material around well screens. The other ranges are not the recommended CBIP range for this aquifer condition.
Junior Engineer • 2020 • Technical Paper-II
A Parshall flume has three principal section-
A)
Converging section; throat section; expanding section
B)
Converging section; parallel section; diverging section
C)
Converging section; throat section; lowering section
D)
Divergence section; throat section; expanding section
A Parshall flume is a flow-measuring device with three main parts: a converging section where the channel narrows, a throat section at the minimum width, and an expanding section where the channel widens again. Hence option (a) is correct. The other options use incorrect section names: a Parshall flume does not have a parallel section as one of its principal sections, and 'lowering section' or 'divergence section' are not standard terms for its main parts.
Junior Engineer • 2020 • Technical Paper-II
According to the ________ law given by Abrahm as a result of many experiments, the strength of well compacted concrete with good workability is dependent only on the water cement ratio.
A)
Water – cement ratio
B)
Water – sand ratio
C)
Water content
D)
Cement content
The statement refers to Abram’s law, which says that for well-compacted concrete made with good materials and adequate curing, the strength depends mainly on the water-cement ratio. As the water-cement ratio decreases, concrete strength generally increases. The other options are incorrect because concrete strength is not primarily governed by water-sand ratio, water content alone, or cement content alone in this law.
Junior Engineer • 2020 • Technical Paper-II
Basic permanent soil conservation structures are-
A)
Drop spillways
B)
Chute spillways
C)
Drop inlet spillways
D)
All of these
Basic permanent soil conservation structures include different types of spillways used to safely dispose excess runoff and prevent erosion. Drop spillways, chute spillways, and drop inlet spillways are all permanent engineering structures commonly used in soil and water conservation works. Therefore, the correct answer is 'All of these'.
Junior Engineer • 2020 • Technical Paper-II
In the Rational method, the runoff coefficient is-
A)
More than one
B)
One
C)
Less than one
D)
None of these
In the Rational method, runoff is estimated as Q = C I A, where C is the runoff coefficient. Since not all rainfall becomes runoff due to infiltration, evaporation, depression storage, and other losses, the coefficient C is generally less than 1. It may approach 1 only for nearly impervious surfaces, but in standard hydrology it is taken as less than one. Hence, option (c) is correct.
Junior Engineer • 2020 • Technical Paper-II
IS 456 : 2000 recommends that exposed surfaces of concrete shall be kept wet for at least ________ from the date of placing concrete in case of OPC.
A)
5 days
B)
6 days
C)
7 days
D)
14 days
IS 456:2000 recommends curing of concrete by keeping exposed surfaces wet for at least 7 days in the case of ordinary Portland cement (OPC). For other types of cement, the curing period is generally longer. Hence, the correct option is (c) 7 days.
Junior Engineer • 2020 • Technical Paper-II
A good brick should not absorb more than ________ of water when soaked.
A)
10%
B)
15%
C)
25%
D)
30%
A good quality first-class brick should absorb not more than 20% of its dry weight of water after 24 hours immersion, but in many civil engineering MCQs the standard criterion for a good brick is taken as not more than 15% for better quality selection. Among the given options, 15% is the correct answer. 10% is too strict, while 25% and 30% are too high and indicate poor quality bricks.
Junior Engineer • 2020 • Technical Paper-II
The outlets of soil conservation structures are designed so that a ________ forms within the downstream portion of the structure and the flow velocity downstream of the structure is reduced to a ________ in the sub-critical range.
A)
Hydraulic jump, erosive level
B)
Hydraulic jump, non-erosive level
C)
Eddy current, less than critical depth
D)
Kinetic engergy, potential energy
In soil conservation structures, the outlet is designed to dissipate excess energy safely. This is achieved by allowing a hydraulic jump to form in the downstream portion of the structure. The hydraulic jump converts supercritical flow to sub-critical flow and greatly reduces the flow velocity to a non-erosive level. Option (a) is incorrect because the goal is not to maintain erosive velocity. Option (c) is not the standard term used here, and option (d) is unrelated to outlet energy dissipation.
Junior Engineer • 2020 • Technical Paper-II
Strength acquired by concrete during the first 7 days is mostly due to hydration of
A)
C3A
B)
C3AF
C)
C3S
D)
C2S
The early strength of concrete, especially in the first 7 days, is mainly due to hydration of tricalcium silicate (C3S). C3S hydrates rapidly and contributes significantly to early strength development. C2S hydrates more slowly and is responsible for later strength. C3A mainly causes very early reactions and affects setting, while C3AF contributes relatively little to strength.
Junior Engineer • 2020 • Technical Paper-II
To accelerate the process of hydration of cement, Calcium chloride upto ________ by weight of cement is generally used as an accelerator.
A)
1.00 %
B)
1.50 %
C)
2.00 %
D)
2.50 %
Calcium chloride is a common accelerator used to speed up the hydration of cement. In standard civil engineering practice, it is generally added in a quantity up to 2% by weight of cement. Beyond this limit, it may cause undesirable effects such as corrosion of reinforcement and may not be recommended. Hence, the correct answer is 2.00%.
Junior Engineer • 2020 • Technical Paper-II
The straight drop spillway is an efficient structure for controlling relatively low heads, normally up to
A)
3 - 4 m
B)
4 - 6 m
C)
6 - 8 m
D)
8 - 10 m
A straight drop spillway is generally used for small to moderate heads and is considered efficient only for relatively low heads, typically up to about 3 to 4 metres. Beyond this range, other spillway types are preferred for better safety and energy dissipation. Hence, option (a) is correct.
Junior Engineer • 2020 • Technical Paper-II
Chains used in chain surveying are
A)
Metric chain
B)
Gunter’s chain
C)
Engineer’s chain
D)
All of these
In chain surveying, different types of chains are used for measuring linear distances. Metric chains, Gunter’s chains, and Engineer’s chains are all standard chains used in surveying. Therefore, the correct answer is 'All of these'. Options (a), (b), and (c) are each individually correct, so (d) is the best choice.
Junior Engineer • 2020 • Technical Paper-II
Adapted land use and soil conservation measures of Contour farming, contour strip cropping and cover cropping, contour bunding or terracing as per ‘standard land capability classification based on land slope’ is
A)
Class-IV with 5-8 per cent slope
B)
Class-I with 0-1 per cent slope
C)
Class-III with 3-5 per cent slope
D)
Class-II with 1-3 per cent slope
In standard land capability classification, land with 5-8% slope falls under Class IV, where adapted land use and soil conservation measures such as contour farming, contour strip cropping, cover cropping, contour bunding, or terracing are recommended. Class I (0-1%) and Class II (1-3%) are nearly level to gently sloping lands needing minimal conservation, while Class III (3-5%) requires more caution but not the same level of intensive soil-conservation measures as Class IV.
Junior Engineer • 2020 • Technical Paper-II
Which of the following is not a means of linear surveying methods?
A)
EDM
B)
Chain
C)
Theodolite
D)
Tape
Linear surveying methods measure distances directly on the ground. Chain and tape are the traditional linear measuring instruments, and EDM (Electronic Distance Measurement) is also used to measure linear distances electronically. A theodolite is mainly used for measuring horizontal and vertical angles, not for linear distance measurement. Therefore, it is not a means of linear surveying methods.
Junior Engineer • 2020 • Technical Paper-II
In ______ operation, determination is made merely of how much one point is below or above another.
A)
Cross-section levelling
B)
Off set levelling
C)
Check levelling
D)
Fly levels
Fly levelling is done quickly to determine the difference in elevation between two points, i.e., how much one point is above or below another. It is used when detailed intermediate readings are not required. Cross-section levelling and offset levelling are used for taking levels of points away from a main line, and check levelling is used to verify the accuracy of levelling work.
Junior Engineer • 2020 • Technical Paper-II
The poissons ratio of a material is 0.20. What will be the ratio of Youngs modulus to bulk modulus?
A)
0.90
B)
1.00
C)
1.40
D)
1.80
For an isotropic material, the relation between Young’s modulus (E), bulk modulus (K), and Poisson’s ratio (ν) is E = 3K(1 - 2ν). Hence, E/K = 3(1 - 2ν). Substituting ν = 0.20 gives E/K = 3(1 - 0.40) = 3 × 0.60 = 1.80. Therefore, the correct ratio of Young’s modulus to bulk modulus is 1.80.
Junior Engineer • 2020 • Technical Paper-II
In a survey, every line has fore bearing and back bearing. The back bearing of a line may be obtained from the fore bearing by the following rule:
A)
Back bearing = Fore bearing + 180°
B)
Back bearing = Fore bearing + 45°
C)
Back bearing = Fore bearing + 90°
D)
Back bearing = Fore bearing + 360°
In surveying, the fore bearing (FB) and back bearing (BB) of the same line differ by 180°. So, if the fore bearing is less than 180°, add 180° to get the back bearing; if it is more than 180°, subtract 180°. Therefore, the correct rule is: Back bearing = Fore bearing + 180° (modulo 360°). The other options are incorrect because 45°, 90°, and 360° do not represent the standard relation between FB and BB.
Junior Engineer • 2020 • Technical Paper-II
Bench mark are fixed reference point of known elevation. There are ________ types of bench mark.
A)
3
B)
2
C)
4
D)
5
In surveying, bench marks are commonly classified into 4 types: GTS bench mark, permanent bench mark, arbitrary bench mark, and temporary bench mark. Therefore, the correct answer is 4. The other options are incorrect because they do not include the complete standard classification.
Junior Engineer • 2020 • Technical Paper-II
Centrifugal pumps are also classified according to-
A)
Impeller types
B)
Number of stages
C)
Both (a) & (b)
D)
None of these
Centrifugal pumps are classified in multiple ways, including by the type of impeller and by the number of stages. Since both are valid classification bases, the correct answer is 'Both (a) & (b)'. Option (a) alone is incomplete, option (b) alone is also incomplete, and (d) is incorrect.
Junior Engineer • 2020 • Technical Paper-II
Look at this series: 3, 1, (1/3), (1/9), ... What number should come next?
A)
1/4
B)
1/32
C)
1/27
D)
1/128
The pattern is division by 3 each time: 3 → 1 → 1/3 → 1/9 → 1/27. So the next number is 1/27. The other options do not follow this pattern.
Junior Engineer • 2020 • Technical Paper-II
Cement Concrete acquires almost ________ of its potential strength and hardness within first 30 days after mixing water.
A)
50 – 60 %
B)
60 – 70 %
C)
70 – 80 %
D)
80 – 90 %
Cement concrete gains most of its strength in the early curing period. By about 28–30 days, it typically acquires nearly 80–90% of its ultimate strength and hardness. Hence option (d) is correct. The lower ranges in the other options underestimate the normal early strength development of concrete.
