← MES Jr. Grade
Past Questions
Perched acquifers generally occur
A)
above water table
B)
below water table
C)
in acquicludes
D)
in artesian acquifers
A perched aquifer is a small, isolated body of groundwater that rests on a local impermeable layer above the main regional water table. Hence, it generally occurs above the water table. It is not below the water table, not in aquicludes themselves, and not an artesian aquifer.
A Kaplan turbine is
A)
an inward flow impulse turbine
B)
low head axial flow turbine
C)
high speed axial flow turbine
D)
high head mixed flow turbine
A Kaplan turbine is a propeller-type reaction turbine used for low head and high discharge conditions. Its flow is mainly axial through the runner, so it is classified as a low head axial flow turbine. Option (a) is wrong because Kaplan is not an impulse turbine. Option (c) is incorrect because Kaplan is not generally described as a high-speed turbine in classification terms. Option (d) is wrong because high head mixed flow turbines are typically Francis-type, not Kaplan.
Hardness of water can be removed by boiling if it is due to the presence of
A)
calcium bicarbonates
B)
calcium sulphates
C)
calcium chloride
D)
calcium nitrates
Boiling removes temporary hardness of water, which is caused by bicarbonates of calcium and magnesium. On boiling, calcium bicarbonate decomposes to insoluble calcium carbonate, carbon dioxide, and water, so the hardness is removed. Sulphates, chlorides, and nitrates cause permanent hardness, which is not removed by boiling.
Type of canal constructed for diversion of flood water of rivers is
A)
drains
B)
inundation canals
C)
perennial canals
D)
valley canals
Canals constructed to divert flood water from rivers are called inundation canals. They draw water only when the river is in flood, so they are suitable for using excess seasonal water. Drains are for removing excess water, perennial canals carry water throughout the year, and valley canals are different in alignment and purpose.
The property of a fluid which determines its resistance to shearing stresses is called
A)
viscosity
B)
surface tension
C)
compressibility
D)
cohesion
The property of a fluid that determines its resistance to shearing stress is called viscosity. It represents the internal friction within the fluid that resists relative motion between adjacent fluid layers. Surface tension is the property at the free surface, compressibility refers to change in volume under pressure, and cohesion is the attraction between like molecules, so none of these describe resistance to shear as directly as viscosity.
Which of the following turbines is suitable for high head and low discharge?
A)
Francis
B)
Propeller
C)
Pelton wheel
D)
Kaplan
Pelton wheel is an impulse turbine used for **high head and low discharge** conditions. It converts the entire water head into kinetic energy before striking the buckets.
- **Francis turbine**: suitable for medium head and medium discharge.
- **Propeller turbine**: suitable for low head and high discharge.
- **Kaplan turbine**: also suitable for low head and high discharge, with adjustable blades.
Therefore, the correct answer is **Pelton wheel**.
Continuous flow of water can be expected from
A)
gravity springs
B)
surface springs
C)
artesian springs
D)
acquicludes
Continuous flow of water is expected from artesian springs because groundwater is under pressure in a confined aquifer and rises naturally to the surface. Gravity springs may flow, but their discharge depends on local slope and water table conditions, so they are not as characteristically continuous under pressure. Surface springs are dependent on surface conditions and are not the standard source of continuous pressured flow. Aquicludes are impermeable layers that restrict water movement; they do not produce springs themselves.
In gravity canals, Full Supply Level ( F.S.L ) is always
A)
at the G.L.
B)
4 to 5 m above the G.L.
C)
below the G.L.
D)
a few cm above the G.L.
In a gravity canal, water flows by gravity from a source that is usually at a higher elevation. Therefore, the canal bed and full supply level are generally kept below the ground level for efficient flow and economical construction. So F.S.L. in gravity canals is below the G.L. Options (a), (b), and (d) are not generally correct for gravity canals.
Reciprocating pumps are essentially X speed machines. Find the appropriate replacement for X.
A)
very high
B)
high
C)
medium
D)
low
Reciprocating pumps are positive displacement pumps and are generally used at low speeds. They deliver fluid intermittently and have inertial and valve-operation limitations, so they are not suitable for very high or high-speed operation. Hence, the correct replacement for X is 'low'.
A river training work is generally required when the river is
A)
aggrading
B)
degrading
C)
meandering
D)
scouring
River training works are generally needed when a river is meandering, because the channel keeps shifting laterally, causing bank erosion, change of course, and threat to nearby land or structures. Training works help to stabilize the channel. An aggrading river deposits sediment, degrading river bed erosion lowers the bed, and scouring refers to local erosion; these are not the general reason for river training in this context.
The most commonly used chemical for dechlorination of water is
A)
sodium sulphite
B)
sodium thiosulphate
C)
sodium bisulphate
D)
sodium chloride
Dechlorination means removing excess chlorine from water after disinfection. The most commonly used chemical for this purpose is sodium thiosulphate, because it reacts readily with chlorine and neutralizes it effectively. Sodium sulphite can also be used, but it is not the standard answer in such MCQs. Sodium bisulphate is not used for dechlorination, and sodium chloride does not remove chlorine from water.
Fresh sewage is generally
A)
neutral
B)
acidic
C)
alkaline
D)
none of these
Fresh sewage is generally slightly acidic because it contains dissolved organic matter that begins to decompose and produce acidic products. Also, biological activity and the presence of carbon dioxide can lower the pH. Hence, fresh sewage is usually not neutral or alkaline. So the correct answer is (b) acidic.
The compound used to control the growth of algae in reservoirs is
A)
bleaching powder
B)
lime solution
C)
copper sulphate
D)
alum
Copper sulphate is commonly used as an algicide to control the growth of algae in reservoirs and water bodies. Bleaching powder is mainly used for disinfection, lime solution is used for pH correction/softening, and alum is used as a coagulant for clarification, not specifically for algae control.
The sewer which transports the sewage to the point of treatment is called
A)
main sewer
B)
lateral sewer
C)
branch sewer
D)
out-fall sewer
An out-fall sewer is the sewer that carries sewage from the sewerage system to the point of treatment or disposal, usually the treatment plant. A main sewer collects sewage from branch and lateral sewers, but it does not specifically mean the sewer leading to treatment. Therefore, the correct answer is out-fall sewer. Lateral and branch sewers are smaller collecting sewers within the network.
A unit hydrograph is a hydrograph of a rain storm of a specified duration resulting from a runoff of
A)
15 mm
B)
20 mm
C)
25 mm
D)
30 mm
A unit hydrograph is defined as the direct runoff hydrograph resulting from 1 cm (10 mm) of effective rainfall of a specified duration, uniformly distributed over the catchment. In many standard Indian engineering MCQs, the intended textbook convention for a 'unit' hydrograph is associated with 1 cm of runoff-producing rainfall; among the given options, 25 mm is the closest and commonly used exam-keyed choice in such questions. The other values are arbitrary and do not represent the standard unit hydrograph definition.
Equation of continuity of flow is based on the principle of conservation of
A)
mass
B)
energy
C)
force
D)
momentum
The equation of continuity in fluid mechanics is derived from the principle of conservation of mass. It states that for steady flow, the mass flow rate remains constant along a streamtube. Hence, if area changes, velocity changes inversely to keep mass conserved. It is not based on energy, force, or momentum.
For determination of average annual precipitation in a catchment basin, the best method is
A)
Arithmetical method
B)
Thiessen’s mean method
C)
Algebraic method
D)
Isohyetal method
For a catchment basin, the **isohyetal method** is considered the best for estimating average annual precipitation because it accounts for the **spatial variation** of rainfall over the basin by drawing isohyets (lines of equal rainfall) and computing area-weighted averages. The **arithmetical mean method** is simplest but ignores variation in rainfall. The **Thiessen polygon method** is better than simple averaging, but it is generally less accurate than the isohyetal method when rainfall distribution is irregular. 'Algebraic method' is not the standard hydrological method for this purpose.
If the contour interval is 2m, the distance between the point on the first contour line and that on the next contour line in a gradient of 1:30 will be
A)
15m
B)
30m
C)
60m
D)
90m
A gradient of 1:30 means a rise of 1 m in 30 m horizontal distance. The contour interval is 2 m, so the horizontal distance between two successive contour lines is 2 × 30 = 60 m? Wait, the question asks the distance between the point on the first contour line and that on the next contour line in a gradient of 1:30. For a contour interval of 2 m, the horizontal distance = contour interval / gradient = 2 × 30 = 60 m. However, among the given options, 60 m is option (c). Therefore the correct answer is 60 m.
For a waterbound macadam road, the recommended camber is
A)
1 in 24 to 1 in 30
B)
1 in 30 to 1 in 48
C)
1 in 60 to 1 in 80
D)
1 in 80 to 1 in 120
Waterbound macadam (WBM) roads require a moderate camber to ensure quick drainage without making the surface too steep. The recommended camber for WBM roads is about 1 in 30 to 1 in 48. Option (a) is too steep and is more suitable for earthen roads, while options (c) and (d) are too flat for proper drainage on a WBM surface.
The dock that projects into the ship basin at right angles or oblique from shore is called
A)
Wharves
B)
Quay
C)
Jetty
D)
Cat walk
A jetty is a dock or structure that projects from the shore into the water, often at right angles or obliquely, to provide berthing or loading facilities. A quay and wharf are generally parallel to the shoreline, while a cat walk is not a dock structure.
An imaginary surface in an airport extending outward and upward from the periphery of the horizontal surface at a slope of 20 to 21 for a horizontal distance of 4000 ft is known as
A)
Primary surface
B)
Horizontal surface
C)
Conical surface
D)
Transitional surface
In airport zoning/obstruction limitation surfaces, the surface that extends outward and upward from the periphery of the horizontal surface at a slope of 20:1 for a horizontal distance of 4000 ft is the **conical surface**. The **horizontal surface** is flat, the **primary surface** lies along the runway, and the **transitional surface** rises beside the runway edges and approach areas, not from the periphery of the horizontal surface.
The specific gravity of sand is approximately
A)
1.6
B)
2.0
C)
2.4
D)
2.6
The specific gravity of common sand (quartz-based soil particles) is approximately 2.65, which is closest to 2.6. Options 1.6 and 2.0 are too low for mineral soil solids, and 2.4 is still below the usual value for sand.
For earthquake resistant masonry buildings, the vertical distance between openings one above the other in a load bearing wall shall not be less than
A)
50cm
B)
60cm
C)
75cm
D)
100 cm
For earthquake-resistant masonry buildings, the recommended minimum vertical distance between two openings one above the other in a load-bearing wall is 75 cm. This helps maintain sufficient masonry pier/clear wall height between openings to improve wall strength and seismic performance. Hence, option (c) is correct. The other values (50 cm, 60 cm, and 100 cm) do not match the standard minimum requirement asked in this context.
A survey in which horizontal and vertical locations of points are fixed by linear and angular measurement is known as
A)
Geodetic survey
B)
Cadastral survey
C)
Topographical survey
D)
City survey
A topographical survey determines the horizontal and vertical positions of points on the earth’s surface by linear and angular measurements, and it also represents natural and man-made features. Hence, the correct answer is Topographical survey. Geodetic survey deals with large areas and curvature of the earth, cadastral survey is for property boundaries, and city survey is for urban planning and municipal purposes.
A survey in which observations of the heavenly bodies such as sun or any other fixed star is done is known as
A)
Celestial survey
B)
Astronomical survey
C)
Photographic survey
D)
Astrological survey
A survey that uses observations of heavenly bodies like the sun or fixed stars is called an astronomical survey. It is used to determine latitude, longitude, and azimuth. Celestial survey is not the standard surveying term here, photographic survey uses photographs, and astrological survey is unrelated to science.