Junior Engineer • 2025 • Paper-IV A (Technical Subject)
What is the modulus of elasticity (E) a measure of?
A)
Yield strength of the material
B)
Stiffness of the material
C)
Ductility of the material
D)
Toughness of the material
Option B is correct: Stiffness of the material.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
Why are spillways essential for dams?
A)
To store additional water during floods
B)
To provide irrigation water during dry seasons
C)
To safely discharge excess water during floods to prevent dam failure
D)
To regulate sediment deposition in reservoirs
Option C is correct: To safely discharge excess water during floods to prevent dam failure.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
A hydraulic structure releases water at a flow rate of 500 cumecs over a spillway with a height of 20 m. Using or adopting Torricelli’s theorem calculate the theoretical velocity of the released water.
A)
12.5 m/s
B)
14 m/s
C)
19.8 m/s
D)
22 m/s
Option C is correct: 19.8 m/s.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
Euler’s buckling formula is applicable for which type of columns?
A)
Short columns
B)
Intermediate columns
C)
Long columns
D)
All columns
Option C is correct: Long columns.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
What is Poisson’s ratio?
A)
Ratio of lateral strain to axial strain
B)
Ratio of shear stress to shear strain
C)
Ratio of axial strain to lateral strain
D)
Ratio of stress to strain
Option A is correct: Ratio of lateral strain to axial strain.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
In a simply supported beam carrying a uniformly distributed load, where is the maximum bending moment?
A)
At the ends of the beam
B)
At the midpoint of the beam
C)
At one-quarter of the beam length
D)
At any random point
Option B is correct: At the midpoint of the beam.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
Which factor does NOT significantly affect the stability of an earthen dam?
A)
Seepage control
B)
Gravity force
C)
Pore water pressure
D)
Soil compaction
Option B is correct: Gravity force.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
Why are sluice gates installed in barrages?
A)
To control the sediment flow and maintain riverbed levels
B)
To increase the storage capacity of the barrage
C)
To divert water for hydroelectric power generation
D)
To regulate the velocity of water entering the canal
Option A is correct: To control the sediment flow and maintain riverbed levels.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
What is the main function of cross regulator in an irrigation system?
A)
To regulate the flow from one river to another
B)
To control the water level in the main canal
C)
To divert water into different branch canals
D)
To measure the discharge in a canal
Option B is correct: To control the water level in the main canal.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
If a masonry dam is 50 m high and the water density is 1000 kg/m³, what is the pressure at the base due to the water column? (g= 9.81 m/s²)
A)
245 kPa
B)
345 kPa
C)
490 kPa
D)
981 kPa
Option C is correct: 490 kPa.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
What is the primary cause of shrinkage in concrete?
A)
Loss of water during hydration
B)
Excess cement
C)
Excessive aggregates
D)
High curing time
Option A is correct: Loss of water during hydration.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
Mohr’s Circle is used for which analysis?
A)
Beam bending
B)
Column buckling
C)
Principal stresses and strains
D)
Torsional analysis
Option C is correct: Principal stresses and strains.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
How does a siphon aqueduct differ from a normal aqueduct?
A)
A siphon aqueduct allows the river to flow above the canal
B)
A siphon aqueduct allows the canal to pass underneath a river by siphon action
C)
A siphon aqueduct requires more energy to operate than a normal aqueduct
D)
A siphon aqueduct is only used in flat terrains
Option B is correct: A siphon aqueduct allows the canal to pass underneath a river by siphon action.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
What is the primary function of a head regulator in a canal system?
A)
To allow excess water to escape from the canal
B)
To regulate and control the entry of water into the canal from the river
C)
To store water for future use
D)
To measure the discharge of water entering the canal
Option B is correct: To regulate and control the entry of water into the canal from the river.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
A concrete beam is designed for a compressive strength of 30 MPa. What is its approximate tensile strength?
A)
1.5 MPa
B)
3.8 MPa
C)
4.5 MPa
D)
6.2 MPa
Option B is correct: 3.8 MPa.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
What is the function of coarse aggregates in concrete?
A)
Reduce shrinkage
B)
Increase workability
C)
Increase strength and durability
D)
Act as a binding agent
Option A is correct: Reduce shrinkage.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
How much fine aggregate is required if a mix contains 1:2:4 (Cement:Sand:Coarse Aggregate) and cement weighs 300 kg?
A)
400 kg
B)
500 kg
C)
600 kg
D)
700 kg
Option C is correct: 600 kg.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
Why are energy dissipaters necessary at the downstream of spillways?
A)
To increase the velocity of water flow
B)
To prevent erosion and structural damage caused by high-energy water
C)
To store additional water for irrigation purposes
D)
To divert water into different canals
Option B is correct: To prevent erosion and structural damage caused by high-energy water.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
Why are cutoff walls provided in hydraulic structures like dams and weirs?
A)
To increase the storage capacity of the reservoir
B)
To allow fish to migrate upstream
C)
To improve the aesthetic appearance of the structure
D)
To prevent seepage and reduce piping failure
Option D is correct: To prevent seepage and reduce piping failure.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
A river carries a discharge of 800 cumecs. If the average depth of flow is 4 m and the width is 50 m, what is the average velocity of the river?
A)
3m/s
B)
4m/s
C)
5m/s
D)
6m/s
Option C is correct: 5m/s.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
Why is river training necessary in hydraulic engineering?
A)
To increase the river’s flow velocity
B)
To control river meandering and prevent erosion
C)
To reduce the depth of the river channel
D)
To increase sediment deposition in floodplains
Option B is correct: To control river meandering and prevent erosion.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
A spillway is designed for a peak flood discharge of 2000 (cumecs or m³/s). If the velocity of flow over the spillway is 8 (m/s) and the depth of flow is 2 meters, what is the required width of the spillway?
A)
100m
B)
125m
C)
200m
D)
250m
Option A is correct: 100m.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
A cantilever beam of length 3 m is subjected to a uniformly distributed load of 5 kKN/m. Using Macaulay’s method, what is the slope at the free end? (EI = 5,000 kNm²)
A)
0.01 rad
B)
0.02 rad
C)
0.03 rad
D)
0.04 rad
Step-by-step solution using Macaulay's Method (or standard beam theory for a cantilever):
1. **Given Data**:
- Length of beam (L) = 3 m
- Uniformly Distributed Load (w) = 5 kN/m
- Flexural Rigidity (EI) = 5,000 kNm²
2. **Bending Moment Equation**:
Let the origin be at the fixed support (x = 0). For a cantilever with a UDL, the bending moment at any section x from the fixed end is:
M(x) = -w(L - x)² / 2
Alternatively, using Macaulay's notation starting from the fixed end, the moment is M(x) = -wLx + (wx²/2) + M_fixed. However, the simplest approach for a cantilever is to integrate the load:
EI(d²y/dx²) = M(x) = -w(L - x)² / 2
3. **Integration for Slope (θ)**:
EI(dy/dx) = ∫ [-w(L - x)² / 2] dx
EI(dy/dx) = -w/2 * [-(L - x)³ / 3] + C₁
EI(dy/dx) = w(L - x)³ / 6 + C₁
4. **Boundary Condition for Slope**:
At the fixed support (x = 0), the slope (dy/dx) = 0.
0 = w(L)³ / 6 + C₁ => C₁ = -wL³ / 6
5. **Slope at the Free End (x = L)**:
EI(θ_free) = w(L - L)³ / 6 + C₁
EI(θ_free) = 0 + (-wL³ / 6)
θ_free = -wL³ / (6EI)
6. **Calculation**:
|θ_free| = (5 kN/m * (3 m)³) / (6 * 5,000 kNm²)
|θ_free| = (5 * 27) / 30,000
|θ_free| = 135 / 30,000
|θ_free| = 0.0045 rad
Wait, let me re-evaluate the standard formula for cantilever UDL slope: θ = wL³/3EI.
Let's check:
θ = (5 * 3³) / (3 * 5000) = 135 / 15000 = 0.009 rad.
Let's re-read the options. The options are 0.01, 0.02, 0.03, 0.04.
If we use the formula θ = wL³/3EI, we get 0.009, which rounds to 0.01 (Option a).
However, let's check if the load was meant to be different or if there's a calculation error.
If w = 15 kN/m, θ = (15*27)/(3*5000) = 0.027 ≈ 0.03.
If L = 4m, θ = (5*64)/(3*5000) = 0.021.
Let's re-calculate wL³/3EI with the given values:
(5 * 27) / (3 * 5000) = 135 / 15000 = 0.009 rad.
Looking at the options provided in typical competitive exams for this specific problem set, there is often a typo in the provided EI or Load. If we assume the standard formula θ = wL³/3EI and the result is 0.009, the closest option is 0.01.
But let's check the integration again.
M = -wx(L - x/2) if x is from free end.
θ = ∫ (wx(L-x/2)/EI) dx = (wLx²/2EI - wx³/6EI).
At x=L: θ = wL³/2EI - wL³/6EI = wL³/3EI.
Calculation: (5 * 27) / (3 * 5000) = 0.009 rad.
Given the options, 0.009 is closest to 0.01. However, if the question intended EI = 1500 or w = 16.6, the answer would change. Based on the provided values, the mathematical result is 0.009 rad, which rounds to 0.01 rad.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
In a stress-strain curve, what does the yield point represent?
A)
The point where the material fractures
B)
The point where plastic deformation begins
C)
The maximum stress the material can withstand
D)
The point where the material returns to its original shape
Option B is correct: The point where plastic deformation begins.
Junior Engineer • 2025 • Paper-IV A (Technical Subject)
Which concrete mix design method is commonly used in India?
A)
ACI method
B)
IS 10262 method
C)
British method
D)
DOE method
Option B is correct: IS 10262 method.
