← MES Jr. Grade
Past Questions
The Java compiler translates source code into
A)
Machine code
B)
Assembly code
C)
Byte code
D)
JVM code
The Java compiler (javac) translates Java source code into bytecode, which is stored in .class files. This bytecode is then executed by the Java Virtual Machine (JVM). It is not translated directly into machine code or assembly code by the compiler, and 'JVM code' is not the standard term.
What is use of eof()?
A)
Returns true if a file open for reading has reached the next character.
B)
Returns true if a file open for reading has reached the next word.
C)
Returns true if a file open for reading has reached the end.
D)
Returns true if a file open for reading has reached the middle.
In C++ file handling, eof() stands for end-of-file. It returns true when the input stream has reached the end of the file, meaning no more characters can be read. Option (a) is incorrect because eof() does not indicate the next character specifically; (b) is incorrect because it has nothing to do with words; and (d) is incorrect because there is no concept of a file 'middle' in eof().
Exception handling is targeted at
A)
Run-time error
B)
Compile time error
C)
Logical error
D)
All of these
Exception handling is used to deal with abnormal situations that occur during program execution, such as divide-by-zero, file not found, or null reference errors. These are run-time errors. Compile-time errors are caught by the compiler, and logical errors are mistakes in program logic; exception handling does not primarily target them. Therefore, the correct answer is Run-time error.
In which file mode open() fails if the file already exists?
A)
ios:: trunk
B)
ios::nocreate
C)
ios::write
D)
ios::noreplace
In C++ file handling, `ios::noreplace` opens a file only if it does not already exist. If the file already exists, `open()` fails.
Why others are incorrect:
- `ios::trunk` (likely meant `ios::trunc`) truncates an existing file, not fail.
- `ios::nocreate` means do not create a new file; it is not the standard mode for failing when a file already exists.
- `ios::write` is used for output/write access and does not by itself cause failure on existing files.
So the correct answer is `ios::noreplace`.
What is dispatch latency?
A)
The time taken by the dispatcher to stop one process and start another
B)
The time taken by the processor to write a file into disk
C)
The whole time taken by all processors
D)
None of these
Dispatch latency is the time required by the operating system's dispatcher to switch the CPU from one process to another. It includes stopping the currently running process, saving its state, and starting the next process. Option (b) is about disk I/O, and (c) is unrelated. Therefore, (a) is correct.
When a base class is privately inherited by the derived class, then
A)
protected members of the base class become private members of derived class
B)
public members of the base class become private members of derived class
C)
both (a) and (b)
D)
only (b)
In private inheritance, the public and protected members of the base class are inherited as private members in the derived class. Therefore, protected members become private, and public members also become private. So both (a) and (b) are correct.
If a line is drawn from A(5,5) to B(13,9) using Bresenham’s Algorithm.Then, if the first pixel is (5,5) then the second pixel is
A)
(7,6)
B)
(6,6)
C)
(8,7)
D)
(9,7)
For the line from A(5,5) to B(13,9), the slope is (9-5)/(13-5) = 4/8 = 0.5, so Bresenham’s algorithm is applied with 0 < m < 1.
Here, dx = 8 and dy = 4.
Initial decision parameter:
p0 = 2dy - dx = 8 - 8 = 0.
Starting pixel is (5,5).
Since p0 = 0, the next step chooses the pixel one unit to the right and one unit up, i.e. (6,6).
So the second pixel is (6,6).
Why others are wrong:
- (7,6) skips a step in x.
- (8,7) and (9,7) are further along the line, not the immediate next pixel.
The effective height of free standing non load bearing wall and column respectively will be (where H is the height of wall or column between centres of supports)
A)
1.0H and 1.0H
B)
1.5H and l.5H
C)
2.0H and l.5H
D)
2.0H and 2.0H
For a free-standing non-load-bearing wall, the effective height is taken as 2.0H. For a column, the effective height is taken as 1.5H. Here H is the actual height between the centres of supports. Therefore, the correct pair is 2.0H and 1.5H.
The side slope of embankments for a railway track is generally taken as
A)
1:1
B)
1.5:1
C)
2:1
D)
1:2
For railway embankments, the side slope is generally taken as 1.5:1 (horizontal:vertical) for stability and economy. A steeper slope like 1:1 may be unsafe, while 2:1 is usually flatter than necessary for normal railway embankments. Hence, 1.5:1 is the standard general value.
Consider the following operations: 1. Drilling, 2. Blasting, 3. Mucking, 4. Placing steel, 5. Placing concrete. The correct sequence of these operations in tunnel construction is
A)
1,2,4,3,5
B)
1,3,2,4,5
C)
1,2,3,4,5
D)
1,3,4,2,5
In conventional tunnel construction, the usual cycle is: drilling the face, blasting to break the rock, mucking to remove the broken material, then placing steel support if required, and finally placing concrete lining. So the correct sequence is 1 → 2 → 3 → 4 → 5. The other options place mucking or support operations before blasting, which is not the correct construction order.
If ‘D’ is the diameter of tunnel in metres, then the thickness of lining in mm, as per the empirical formula is given by
A)
42 D
B)
82 D
C)
104 D
D)
124 D
For tunnel lining, the commonly used empirical formula gives the thickness of lining in millimetres as about 82 times the tunnel diameter in metres. Hence, if D is the diameter of the tunnel, thickness = 82D mm. The other options are not the standard empirical value used in tunnel engineering.
The two point problem and three point problem are methods of
A)
resection
B)
orientation
C)
traversing
D)
resection and orientation
The two-point problem and three-point problem are classic methods used in plane table surveying for determining the position of the plane table station. These are treated under resection, and they also involve orientation of the table. Hence, the best answer is 'resection and orientation'. Option (a) is incomplete, while traversing is a different surveying method.
When the speed of traffic flow becomes zero, then
A)
traffic density attains maximum value whereas traffic volume becomes zero
B)
traffic density and traffic volume both attain maximum value
C)
traffic density and traffic volume both become zero
D)
traffic density becomes zero whereas traffic volume attains maximum value
In traffic flow theory, volume (flow) is the number of vehicles passing a point per unit time, and speed is the rate of movement. If speed becomes zero, vehicles are stationary, so no vehicles pass the point per unit time; hence traffic volume becomes zero. At the same time, vehicles can accumulate on the road, so traffic density becomes maximum. Therefore, option (a) is correct. The other options are incorrect because zero speed does not imply zero density, and volume cannot be maximum when vehicles are not moving.
Critical path
A)
is always longest
B)
is always shortest
C)
may be longest
D)
may be shortest
In CPM/PERT, the critical path is the path with the maximum total duration through the project network. It determines the minimum possible project completion time, so it is always the longest path in terms of time. The other options are incorrect because the critical path cannot be the shortest path; it is defined by the longest duration among all paths.
Water retentivity for brick masonry should not be less than
A)
50%
B)
60%
C)
70%
D)
80%
Water retentivity of bricks is the ability to retain water needed for proper hydration of mortar. For brick masonry, it should not be less than 70% so that the mortar does not lose water too quickly and bond strength is maintained. Hence, 70% is the correct minimum value. The other options are below the standard requirement.
The type of surveying which requires least office work is
A)
tacheometry
B)
trigonometrical levelling
C)
plane table surveying
D)
theodolite surveying
Plane table surveying requires the least office work because the field observations and plotting are done simultaneously on the drawing sheet at the site itself. Hence, very little post-survey office computation or plotting is needed. In contrast, tacheometry, trigonometrical levelling, and theodolite surveying involve more measurements and calculations in the office.
Which of the following surfaces will give highest coefficient of traction while using crawler track tractors?
A)
Ice
B)
Concrete
C)
Loose sand
D)
Earth
Crawler track tractors develop the highest traction on hard, firm surfaces because the track can grip without excessive sinkage or slippage. Among the given options, concrete provides the best support and friction, so it gives the highest coefficient of traction. Ice gives the least traction due to very low friction, loose sand causes sinkage and reduced grip, and earth is better than sand but still inferior to concrete.
Which of the following is a component of a shield for tunnelling?
A)
liner plate
B)
trench jack
C)
stiffener
D)
cutting edge
A shield used in tunnelling has a cutting edge at its front to help it penetrate the soil and support excavation. Liner plates are used for lining, trench jacks are used in trench support systems, and stiffeners are structural members but not the main identifying component of a tunnelling shield.
The stopping sight distance depends upon
A)
total reaction time of driver
B)
speed of vehicle
C)
efficiency of brakes
D)
all of these
Stopping sight distance (SSD) is the total distance required for a vehicle to stop safely after the driver perceives an obstruction. It depends on: (1) the driver's reaction time, because the vehicle continues moving during perception and reaction; (2) the speed of the vehicle, because higher speed increases both reaction and braking distance; and (3) the efficiency of the brakes, because better braking reduces the braking distance. Therefore, all the given factors affect SSD.
The water content of soil, which represents the boundary between plastic state and liquid state is known as
A)
liquid limit
B)
plastic limit
C)
shrinkage limit
D)
plasticity index
The water content at which soil changes from the plastic state to the liquid state is called the liquid limit. The plastic limit is the boundary between semi-solid and plastic states, the shrinkage limit is between semi-solid and solid states, and the plasticity index is the range of water content between liquid limit and plastic limit.
The maximum total settlement for isolated foundations on clayey soils should be limited to
A)
25 mm
B)
40 mm
C)
65 mm
D)
100 mm
For isolated foundations on clayey soils, the commonly accepted permissible maximum total settlement is about 65 mm. This is a standard serviceability limit used in foundation design for cohesive soils. The other options are either too low for general isolated footings on clay or too high for the usual recommended limit.
Which of the following is not a PERT event?
A)
site investigation started
B)
sessional work completed
C)
bus starts from Jaipur
D)
class is being attended
PERT events are specific milestones or instantaneous points in a project, not activities that take time.
- (a) site investigation started: a definite event/milestone.
- (b) sessional work completed: a clear completion event.
- (c) bus starts from Jaipur: a point event.
- (d) class is being attended: this is an ongoing activity, not an event.
Therefore, the option that is not a PERT event is (d).
The ruling design speed on a National Highway in plain terrain as per IRC recommendations is
A)
60 kmph
B)
80 kmph
C)
100 kmph
D)
120 kmph
As per IRC recommendations, the ruling design speed for a National Highway in plain terrain is 100 kmph. In plain terrain, highways are designed for higher speeds than in rolling or mountainous terrain due to better alignment and visibility. Hence, option (c) is correct.
The transition curve used in the horizontal alignment of highways as per IRC recommendations is
A)
spiral
B)
lemniscate
C)
cubic parabola
D)
any of these
As per IRC recommendations, the transition curve in horizontal highway alignment may be any of the standard forms such as spiral (clothoid), cubic parabola, or lemniscate, provided it satisfies the required design criteria. Therefore, the correct choice is 'any of these'. Options (a), (b), and (c) are all acceptable transition curve forms, so none of them alone is the only correct answer.
According to ICAO, all markings on the runways are
A)
Yellow
B)
White
C)
Black
D)
Red
According to ICAO standards, runway markings are white. Specifically, runway centerline, threshold, aiming point, designation, and touchdown zone markings are painted white for contrast and visibility. Yellow is used for taxiway markings, not runway markings. Therefore, the correct option is (b) White.