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Past Questions — 2025
The fuel for Small Hydel Project is:-
A)
Water
B)
Petrol
C)
Hydrogen
D)
Diesel
A Small Hydel Project (Small Hydroelectric Project) is a system that generates electricity by harnessing the kinetic and potential energy of flowing or falling water. In this context, 'fuel' refers to the primary energy source that drives the turbine. Water flows through a penstock to rotate a turbine, which in turn rotates a generator to produce electricity. Unlike thermal power plants, hydroelectric projects do not consume chemical fuels; they utilize the natural water cycle.
- Option b (Petrol), Option c (Hydrogen), and Option d (Diesel) are chemical fuels used in internal combustion engines or fuel cells, which are not the energy source for a hydroelectric project.
In a mortar, the binding material is:-
A)
Cement
B)
Sand
C)
Surkhi (Brick dust)
D)
Cinder
Mortar is a mixture of a binding material, a fine aggregate, and water.
1. Binding Material: This is the component that undergoes a chemical reaction (hydration) to harden and bind the aggregate particles together. Common binding materials include Cement, Lime, or Gypsum. In modern construction, Cement is the most widely used binding agent.
2. Fine Aggregate: This is the filler material that provides bulk and reduces shrinkage. Examples include Sand, Surkhi (brick dust), or Cinder.
Evaluating the options:
- Option (a) Cement: Correct. It acts as the glue/binder that holds the mortar together.
- Option (b) Sand: Incorrect. Sand is the fine aggregate (filler).
- Option (c) Surkhi: Incorrect. Surkhi is a pozzolanic material used as a substitute for sand (fine aggregate).
- Option (d) Cinder: Incorrect. Cinder is used as a lightweight fine aggregate.
The excess power available over the firm power during the off peak hours is:-
A)
Firm power
B)
Secondary power
C)
Installed capacity
D)
Peak load
In hydroelectric power plant terminology, power is categorized based on its reliability and availability:
1. **Firm Power**: This is the minimum amount of energy that a power plant can guarantee to deliver to the grid continuously throughout the year, regardless of the season or water availability.
2. **Secondary Power**: This is the power available over and above the firm power. It is typically available during the off-peak hours or during periods of high water inflow (monsoon). Because it depends on water availability and is not guaranteed 100% of the time, it is termed 'secondary'.
3. **Installed Capacity**: This is the maximum theoretical power output the plant can produce if all turbines are running at full capacity; it is a physical limit, not a category of available power over firm power.
4. **Peak Load**: This refers to the maximum demand placed on the electrical grid at a specific time, not the power generated by the plant.
Therefore, the excess power available over the firm power is defined as Secondary Power.
The stone suitable for rubble masonry should be:-
A)
Hard
B)
Tough
C)
Heavy
D)
Light
In rubble masonry, stones are used in their natural or roughly dressed state. For a structure to be durable and capable of bearing loads, the stones must possess high compressive strength and resistance to wear and weathering. 'Hardness' is the primary property that ensures the stone does not crumble under pressure or erode over time.
Analysis of options:
- (a) Hard: Correct. Hardness ensures durability and strength, which are essential for load-bearing masonry.
- (b) Tough: While toughness (resistance to fracture) is a positive trait, hardness is the fundamental requirement for the overall stability and longevity of rubble masonry.
- (c) Heavy: Weight is a characteristic of the stone's density, not necessarily a requirement for suitability. Excessively heavy stones can make construction difficult without adding structural value.
- (d) Light: Light stones are generally avoided in load-bearing rubble masonry as they often lack the necessary strength and stability.
Where does the neutral axis by Working Stress Method of the reinforced beam pass through?
A)
Centre of gravity of the concrete section
B)
Centroid of the transformed section
C)
Centroid of the concrete section
D)
Centroid of the structure
In the Working Stress Method (WSM) of reinforced concrete design, the beam is analyzed based on the principle of linear elasticity. Since concrete and steel have different moduli of elasticity (E_s and E_c), the steel area is replaced by an equivalent area of concrete that would provide the same stiffness. This is done using the modular ratio (m = E_s / E_c). The resulting section, consisting of the concrete area and the 'transformed' steel area, is known as the Transformed Section. The neutral axis is the axis about which the section bends and where the stress is zero; for a linearly elastic material, this axis must pass through the centroid of the entire transformed section.
Why other options are incorrect:
- Option (a) and (c): The center of gravity or centroid of the concrete section alone ignores the contribution of the reinforcement, which shifts the neutral axis downward.
- Option (d): 'Centroid of the structure' is a general term referring to the entire building or assembly, not the specific cross-section of the beam.
Concrete cover is provided to protect the steel reinforcement against:-
A)
Corrosion
B)
Shrinkage
C)
Buckling
D)
Dust
Concrete cover is the distance between the outer surface of the concrete and the outer surface of the reinforcement. Its primary purposes are: 1. Protection against Corrosion: Steel is prone to rusting (oxidation) when exposed to moisture, oxygen, and chlorides. The alkaline nature of concrete creates a passive layer around the steel; the cover ensures this layer remains intact and prevents external corrosive agents from reaching the reinforcement. 2. Fire Resistance: It protects the steel from losing strength rapidly during a fire.
Why other options are incorrect:
- b. Shrinkage: Shrinkage is a property of the concrete mix itself (loss of moisture); cover does not prevent the concrete from shrinking.
- c. Buckling: Buckling is a structural failure of slender members under compression; it is prevented by lateral bracing and proper design, not by concrete cover.
- d. Dust: While cover physically separates steel from dust, dust is not a structural threat to reinforcement; corrosion is the critical chemical threat.
Small Hydel Projects are generally considered as:-
A)
Renewable and sustainable
B)
High maintenance
C)
Environmentally damaging
D)
Expensive to operate
Step-by-step reasoning:
1. Definition: Small Hydel Projects (SHPs) are hydroelectric power plants that typically generate a small amount of electricity (usually up to 25 MW, though definitions vary by region).
2. Renewable Nature: They utilize the natural flow of water (the water cycle), which is naturally replenished by rainfall, making them a 'renewable' energy source.
3. Sustainability: Unlike large-scale dams, SHPs often use 'run-of-the-river' technology, which requires little to no reservoir storage. This minimizes the displacement of people and the flooding of forests, making them 'sustainable' and environmentally friendly.
4. Analysis of other options:
- Option (b) 'High maintenance': SHPs are generally designed for simplicity and lower maintenance compared to massive industrial power plants.
- Option (c) 'Environmentally damaging': While any construction has some impact, SHPs are specifically praised for having a significantly lower environmental footprint than large hydro projects.
- Option (d) 'Expensive to operate': Once the initial capital investment is made, the operational cost of hydropower is among the lowest of all energy sources because the 'fuel' (water) is free.
When a vehicle traces a horizontal curve, it is subjected to centrifugal force in a direction of:-
A)
Inward
B)
Outward
C)
Forward
D)
Upward
When a vehicle moves along a horizontal curve, it undergoes circular motion. According to the laws of physics, any object moving in a curved path experiences a 'centrifugal force'. This is an apparent force (inertial force) that acts in the direction opposite to the centripetal force. While the centripetal force (provided by friction and superelevation) acts inward toward the center of the curve to keep the vehicle on track, the centrifugal force acts radially outward, away from the center of the curve.
- Option (a) Inward: This is the direction of the centripetal force, not the centrifugal force.
- Option (c) Forward: This is the direction of the vehicle's velocity/momentum, not the radial force.
- Option (d) Upward: This is the direction opposite to gravity and does not relate to the horizontal curvature of the path.
The “Head” in a Small Hydel Project is:-
A)
The depth of the river
B)
The depth of the reservoir
C)
The difference in elevation between the water surface at the intake and the turbine
D)
The length of the penstock
In hydroelectric power generation, 'Head' refers to the vertical distance that water falls from the intake point to the turbine. This elevation difference creates the potential energy that is converted into kinetic energy as water flows down the penstock, and finally into mechanical energy by the turbine.
- Option (a) is incorrect because the depth of the river does not determine the energy potential available for power generation.
- Option (b) is incorrect because while the reservoir depth contributes to the total head, the 'Head' is specifically the difference between the intake level and the turbine level, not just the depth of the pool.
- Option (d) is incorrect because the length of the penstock refers to the distance the water travels, which affects friction losses (head loss), but it is not the definition of the 'Head' itself.
The unit weight per running meter of 12 mm dia. steel bar is:-
A)
0.89 kg
B)
0.62 kg
C)
0.78 kg
D)
0.65 kg
To calculate the unit weight of a steel bar per running meter, we use the standard formula derived from the volume of a cylinder and the density of steel.
1. **Formula**: The weight of a steel bar is given by:
Weight (W) = Volume × Density
W = (π/4 × d² × L) × ρ
Where:
- d = diameter of the bar (in meters)
- L = length of the bar (1 meter for unit weight)
- ρ = density of steel (standard value is 7850 kg/m³)
2. **Simplified Formula**: For steel bars, the formula is commonly simplified to:
W = (d² / 162.2) kg/m
(where d is in millimeters)
3. **Calculation for 12 mm bar**:
W = (12)² / 162.2
W = 144 / 162.2
W ≈ 0.8877 kg/m
4. **Rounding**: Rounding to two decimal places, we get 0.89 kg/m.
Comparing this result with the given options:
- Option (a) 0.89 kg matches our calculation.
- Option (b) 0.62 kg corresponds to a 10 mm bar (10²/162.2 ≈ 0.617).
- Option (c) 0.78 kg is incorrect.
- Option (d) 0.65 kg is incorrect.
The net amount of power which is continuously available from a plant is:-
A)
Firm power
B)
Secondary power
C)
Installed capacity
D)
Primary power
In hydroelectric power plant terminology, power is categorized based on its reliability and availability throughout the year:
1. **Firm Power (Correct):** This is the amount of power that can be guaranteed to be available continuously during the most critical period (usually the driest season) of the year. It is the 'reliable' power that the plant can commit to the grid regardless of seasonal fluctuations in water flow.
2. **Secondary Power:** This is the power available in addition to the firm power. It depends on the availability of surplus water (e.g., during monsoon seasons) and cannot be guaranteed continuously throughout the year.
3. **Installed Capacity:** This refers to the maximum theoretical power output that the plant can produce if all turbines are running at full load. It is a measure of the plant's size, not its continuous availability.
4. **Primary Power:** While 'primary' often refers to the main source of energy, in the context of power availability and reliability in hydel projects, 'Firm Power' is the specific technical term used for continuous availability.
The Small Hydel Project without reservoirs where water is used at the rate at which it runs in the river is called:-
A)
Diversion weir
B)
Pump storage pump
C)
Run-of-the-river
D)
Head loss
A Run-of-the-river (ROR) hydroelectric project is a type of hydroelectric generation where little or no water storage is provided. Instead of using a large reservoir (dam) to store water for later use, the plant utilizes the natural flow and elevation drop of the river to generate electricity. The water is diverted from the river, passed through a turbine, and returned to the river downstream.
Analysis of other options:
- a. Diversion weir: This is a structure used to divert water from a river into a canal or penstock, but it is a component of a project, not the name of the project type itself.
- b. Pump storage pump: This refers to a system that stores energy by pumping water from a lower reservoir to an upper reservoir during low demand and releasing it during peak demand; it requires reservoirs.
- d. Head loss: This is a hydraulic term referring to the reduction in the total head (pressure) of a fluid as it moves through a system due to friction or turbulence; it is not a type of project.
The least cover provided in beam is:-
A)
20 mm
B)
25 mm
C)
30 mm
D)
15 mm
In Reinforced Cement Concrete (RCC) design, 'cover' refers to the distance between the outer surface of the concrete and the outer surface of the reinforcement. This cover is essential to protect the steel from corrosion and to provide fire resistance. According to standard codes of practice (such as IS 456:2000), the nominal cover for beams is generally specified as 25 mm for mild exposure conditions. While slabs may have a smaller cover (e.g., 15-20 mm) and columns or foundations may have larger covers (40-50 mm), the standard minimum nominal cover for a beam in general construction is 25 mm. Therefore, among the given options, 25 mm is the recognized standard least cover for beams.
The key factor in determining the power output of a Small Hydel Project is:-
A)
The size of the penstock
B)
The type of turbine used
C)
The head and flow rate of water
D)
The material of the dam
The power output of any hydroelectric project, including Small Hydel Projects (SHP), is fundamentally determined by the potential energy of the water. The theoretical power (P) is calculated using the formula: P = ρ × g × Q × H × η, where:
1. ρ (rho) is the density of water,
2. g is the acceleration due to gravity,
3. Q is the flow rate (discharge) in cubic meters per second,
4. H is the net head (the vertical distance the water falls),
5. η (eta) is the efficiency of the system.
Since ρ and g are constants, the power output is directly proportional to the product of the Head (H) and the Flow Rate (Q).
Why other options are incorrect:
- Option (a): The size of the penstock affects the friction losses (head loss), but it does not determine the available power potential of the site.
- Option (b): The type of turbine is selected *based* on the head and flow rate to maximize efficiency, but the turbine itself does not create the power; it only converts the existing potential energy into mechanical energy.
- Option (d): The material of the dam is a structural/civil engineering consideration for stability and cost, and has no direct impact on the power generation formula.
The mix ratio for M-20 grade of concrete is:-
A)
1:1.5:3
B)
1:2:4
C)
1:3:6
D)
1:2:6
In concrete technology, the grade of concrete (e.g., M-20) refers to the characteristic compressive strength of a 150mm cube at 28 days (M stands for Mix and 20 stands for 20 N/mm²). For nominal mixes (standard proportions used for small-scale works), the ratios are defined as follows:
1. M-20 Grade: The nominal mix ratio is 1:1.5:3 (1 part Cement : 1.5 parts Fine Aggregate/Sand : 3 parts Coarse Aggregate).
2. M-15 Grade: The nominal mix ratio is 1:2:4 (Option b).
3. M-10 Grade: The nominal mix ratio is 1:3:6 (Option c).
4. Option d (1:2:6) is not a standard nominal mix for these common grades.
Therefore, for M-20 grade concrete, the correct proportion is 1:1.5:3.
Strength of cement concrete primarily depends upon:-
A)
Quality of water
B)
Quantity of aggregate
C)
Quantity of cement
D)
Water-cement ratio
The strength of concrete is primarily governed by the 'Abrams' Law', which states that for a given water-cement ratio, the strength of the concrete is independent of the amount of cement used, provided the mix is workable. The water-cement (w/c) ratio is the ratio of the weight of water to the weight of cement used in the concrete mix. A lower w/c ratio generally leads to higher strength and lower permeability because it reduces the volume of capillary pores formed when excess water evaporates from the hardened cement paste.
Why other options are incorrect:
- a. Quality of water: While water quality is important to prevent contamination or premature setting (e.g., avoiding salts or organic matter), it does not 'primarily' determine the strength level.
- b. Quantity of aggregate: Aggregates act as fillers and provide stability; while their grading and quality matter, they do not dictate the fundamental strength of the cement paste matrix.
- c. Quantity of cement: Increasing the quantity of cement without adjusting the water content does not necessarily increase strength; in fact, if the w/c ratio remains high, the strength will remain low regardless of the cement volume.
Which of the following is not a requirement for site selection of Small Hydel Project?
A)
Availability of water
B)
Large catchment area
C)
Sedimentation
D)
Rocky land
To determine the correct answer, we must analyze the specific requirements for a 'Small Hydel Project' (SHP) compared to large-scale hydroelectric dams.
1. **Availability of water (Option a):** This is a fundamental requirement for any hydel project. Without a consistent flow or volume of water, power generation is impossible.
2. **Large catchment area (Option b):** This is NOT a requirement for Small Hydel Projects. SHPs are typically 'run-of-river' projects or utilize small streams/canals. They are designed to operate with the available natural flow of a small stream and do not require a massive catchment area or a large reservoir, which are characteristics of Large Hydel Projects.
3. **Sedimentation (Option c):** While sedimentation is a problem, 'considering sedimentation' is a critical requirement for site selection. A site with excessive siltation would lead to turbine erosion and reservoir filling, making it unsuitable. Therefore, analyzing sedimentation is a requirement.
4. **Rocky land (Option d):** Rocky terrain is highly desirable for site selection because it provides a strong foundation for the weir, intake structures, and powerhouse, and it reduces the risk of seepage and landslides.
Since a large catchment area is only necessary for large-scale storage projects and not for small-scale projects, option (b) is the correct answer.
The characteristic used to define the grade of concrete is:-
A)
Tensile strength
B)
Compressive strength
C)
Density
D)
Neutral axis
In concrete technology, the 'grade' of concrete refers to its strength class. According to standard codes (such as IS 456:2000), the grade of concrete is denoted by the letter 'M' (which stands for Mix) followed by a number. This number represents the characteristic compressive strength of 150 mm cubes at 28 days, measured in N/mm². For example, M25 concrete has a characteristic compressive strength of 25 N/mm².
Why other options are incorrect:
- a. Tensile strength: Concrete is naturally weak in tension; while it is measured (often as split tensile strength), it is not used to define the grade.
- c. Density: Density relates to the weight of the concrete (e.g., lightweight or heavyweight concrete) but does not define the structural grade.
- d. Neutral axis: This is a geometric concept in structural analysis (the axis where there is no longitudinal stress) and is not a material property used for grading concrete.
The minimum diameter of steel in Column is:-
A)
12 mm
B)
10 mm
C)
16 mm
D)
20 mm
According to IS 456:2000 (the Indian Standard code of practice for Plain and Reinforced Concrete), which governs RCC design in India and is the standard for MPSC exams, the minimum diameter of longitudinal reinforcement bars in a column is specified to ensure structural stability and prevent buckling of the bars. Specifically, Clause 26.5.3.1 states that the minimum diameter of longitudinal reinforcement bars shall be 12 mm.
- Option (a) 12 mm: Correct, as per IS 456:2000.
- Option (b) 10 mm: Incorrect; this is often used for stirrups or ties, but not for main longitudinal reinforcement in columns.
- Option (c) 16 mm: Incorrect; while 16 mm is commonly used, it is not the minimum requirement.
- Option (d) 20 mm: Incorrect; this is a standard bar size but not the minimum requirement.
Penstocks are opened or closed conduits that carry water to the:-
A)
Forebay
B)
Power channel
C)
Turbines
D)
Reservoir
In a hydroelectric power plant, the penstock is a high-pressure pipeline that conveys water from the reservoir or forebay down to the turbines. Its primary purpose is to convert the potential energy of the stored water into kinetic energy by directing it at high velocity and pressure onto the turbine blades to rotate the generator.
Why other options are incorrect:
- a. Forebay: The forebay is the basin that stores water immediately before it enters the penstock; the penstock starts from the forebay, it does not carry water to it.
- b. Power channel: The power channel (or headrace canal) is used to transport water from the intake to the forebay; it precedes the penstock in the system.
- d. Reservoir: The reservoir is the primary storage source at the highest elevation; water flows from the reservoir toward the turbines, not the other way around.
The slope of stair should not exceed:-
A)
300
B)
400
C)
350
D)
450
In the context of building materials and construction standards for stairs, the 'slope' refers to the ratio of the rise to the run (tread). While the options are presented as numbers (300, 400, 350, 450), in engineering exam nomenclature for this specific topic, these typically represent ratios or degrees. For general residential and public buildings, the recommended slope of a staircase is usually between 25° and 40°. A slope exceeding 40° (represented here as 400 or 40 degrees in some shorthand notations used in departmental exams) is considered too steep for safe and comfortable movement. Therefore, the slope should not exceed 40°. Option (b) 400 corresponds to the 40° limit commonly cited in building codes for standard stairs.
The common feature in hill road is:-
A)
U turn
B)
Hair pin bend
C)
Speed limit
D)
Landslide
In Transportation Engineering, specifically in the design of hill roads, a 'Hair pin bend' is a characteristic feature used to gain elevation in steep terrain where the slope is too great for a straight road. It is a sharp curve (usually 180 degrees) that allows the road to 'fold' back on itself to climb a mountain.
Reasoning for other options:
- a. U turn: While similar in shape, a U-turn is a maneuver used to reverse direction on a road, whereas a hair pin bend is a permanent structural design element of the road alignment.
- c. Speed limit: Speed limits exist on all types of roads (plain, urban, highway), so it is not a feature specific or unique to hill roads.
- d. Landslide: A landslide is a natural disaster or a geological hazard that may occur on hill roads, but it is not a 'feature' of the road design; it is a failure of the slope.
The structure that allows overflow of water to the downstream side when the reservoir is full is called:-
A)
Power channel
B)
Penstock
C)
Spillway
D)
Forebay
A spillway is a structure used in dam construction to provide the controlled release of water from a reservoir into the downstream area. Its primary purpose is to prevent the dam from being overtopped during floods or when the reservoir reaches its maximum capacity, which could otherwise lead to structural failure of the dam.
Why other options are incorrect:
- a. Power channel: This is the conduit that carries water from the intake/forebay to the surge tank or penstock to generate power.
- b. Penstock: This is a high-pressure pipe that delivers water from the reservoir or forebay directly to the turbines.
- d. Forebay: This is a holding basin located at the end of the headrace canal and the beginning of the penstock, used to regulate water flow and remove sediment before it enters the turbine.
Which type of irrigation method uses supply ditch, borders, ridges?
A)
Border Flooding
B)
Check Flooding
C)
Basin Flooding
D)
Drip Irrigation Method
Border irrigation is a surface irrigation method where the field is divided into a series of parallel strips (borders) separated by low ridges (levees). Water is delivered from a supply ditch (head ditch) and allowed to flow down the length of the border by gravity.
1. **Border Flooding (Correct):** It specifically utilizes supply ditches to bring water to the head of the strip and ridges to confine the water within the border, preventing it from flowing into adjacent strips.
2. **Check Flooding:** In this method, the field is divided into small, square or rectangular plots (checks) surrounded by embankments. Water is applied to cover the entire area of the check; it does not typically involve the long, narrow strip configuration characteristic of 'borders'.
3. **Basin Flooding:** This is used for orchards or trees where water is applied to a circular or square basin around the plant. It does not use the 'border and ridge' system for field-wide distribution.
4. **Drip Irrigation:** This is a micro-irrigation system using pipes and emitters to apply water directly to the root zone. It does not use supply ditches or ridges for water containment.
Which factors govern the shape of a hydrograph?
A)
Climatic factors
B)
River characteristics
C)
Climatic and physiographic factors
D)
Physiographic factors
A hydrograph is a plot of discharge versus time at a specific point in a river basin. The shape of a hydrograph (including the peak flow, time to peak, and recession limb) is governed by two primary categories of factors:
1. **Climatic Factors**: These include the nature of the precipitation (intensity, duration, and distribution of rainfall) and evaporation rates. For example, high-intensity rainfall over a short duration leads to a steep rising limb and a higher peak.
2. **Physiographic Factors**: These relate to the physical characteristics of the watershed, such as the basin area, shape of the catchment, slope of the terrain, soil type (infiltration capacity), land use/land cover (vegetation), and the drainage density of the river network.
Since both the weather conditions (climatic) and the physical layout of the land (physiographic) simultaneously determine how rainfall is converted into runoff, the correct answer is the combination of both.