1.
Starting friction is low in:
Correct Answer
A. Hydrostatic lubrication
Explanation
In hydrostatic lubrication, a fluid film is created between the moving surfaces by the pressure of an external fluid source. This fluid film helps to separate the surfaces and reduce friction. As a result, the starting friction in hydrostatic lubrication is low compared to other types of lubrication.
2.
Which of the following would not increase the rate of heat transferred from a heater pipe?
Correct Answer
D. Placing the heater pipe within another whose thermal conductivity is smaller in number and 2 inches thick
Explanation
Placing the heater pipe within another pipe whose thermal conductivity is smaller and 2 inches thick would not increase the rate of heat transferred from the heater pipe. This is because the outer pipe with lower thermal conductivity would act as an insulating layer, reducing the heat transfer between the heater pipe and the surroundings.
3.
By adding tetraethyl lead to iso-octane:
Correct Answer
C. Octane number above 100 can be obtained
Explanation
By adding tetraethyl lead to iso-octane, the octane number can be increased above 100. The octane number is a measure of a fuel's ability to resist knocking or detonation in an engine. Typically, higher octane numbers indicate fuels that are less likely to cause knocking. By adding tetraethyl lead, which is an octane booster, to iso-octane, the octane number can be further increased, potentially surpassing the typical maximum octane rating of 100.
4.
Which of the following is psychrometric process?
Correct Answer
D. D) All of the above
Explanation
The correct answer is d) All of the above. This means that all of the given options - humidification, dehumidification, and sensible heating - are psychrometric processes. Psychrometric processes involve the study and analysis of the properties of moist air and its behavior when subjected to various changes in temperature, humidity, and pressure. Humidification refers to the process of adding moisture to the air, dehumidification involves removing moisture from the air, and sensible heating is the process of increasing the temperature of the air without changing its humidity content.
5.
Process used to improve fatigue resistance of the metal by setting up compressive stresses in its surface is known as:
Correct Answer
C. Cold peening
Explanation
Cold peening is a process used to improve the fatigue resistance of metal by creating compressive stresses on its surface. During cold peening, small, repeated impacts are applied to the metal surface using a hard material such as steel shot or glass beads. These impacts cause the surface of the metal to deform, creating compressive stresses that help to counteract the tensile stresses that can lead to fatigue failure. This process can increase the lifespan and durability of the metal, making it more resistant to fatigue and improving its overall performance.
6.
The stress produced by a suddenly applied load as compared to that produced by the same load when applied gradually is:
Correct Answer
B. 2 times
Explanation
When a load is applied suddenly, it creates a rapid change in the force distribution within the material, causing stress concentrations. This sudden change in loading results in a higher stress magnitude compared to when the load is applied gradually. Therefore, the stress produced by a suddenly applied load is 2 times higher than the stress produced by the same load when applied gradually.
7.
A line of thrust of a parabolic arch is:
Correct Answer
A. Funicular Polygon
Explanation
The line of thrust of a parabolic arch is a funicular polygon. A funicular polygon is a polygon in which all the sides are in equilibrium under the action of a system of forces. In the case of a parabolic arch, the line of thrust follows the shape of the arch, creating a curve that is in equilibrium. This curve, known as a funicular polygon, is the correct answer.
8.
If the angularity number of an aggregate is increased then the workability of the concrete will:
Correct Answer
C. No Change
Explanation
Increasing the angularity number of an aggregate refers to increasing the number of sharp, rough edges and irregular shapes in the aggregate particles. This can lead to a decrease in the workability of the concrete. Workability refers to the ease with which the concrete can be mixed, placed, and compacted. When the aggregate has a higher angularity number, it tends to interlock and create a more rigid mixture, making it harder to work with. Therefore, the workability of the concrete will decrease when the angularity number of the aggregate is increased.
9.
If the column has machined end then the connection between the splice and column is designed to carry:
Correct Answer
B. 50% axial load and any tension
Explanation
The connection between the splice and column is designed to carry 50% axial load and any tension. This means that the connection is capable of withstanding half of the axial load applied to the column, as well as any tension forces that may be present. The machined end of the column allows for a stronger and more secure connection, enabling it to handle higher loads.
10.
The depth of capillary fringe in a soil mass having void ratio = 0.70 and effective size of the soil grain D10= 0.1 mm will be:
Correct Answer
A. 34.5 cm
Explanation
The depth of the capillary fringe in a soil mass is determined by the void ratio and effective size of the soil grain. In this case, with a void ratio of 0.70 and an effective size of 0.1 mm, the depth of the capillary fringe is calculated to be 34.5 cm.
11.
A streamlined body is defined as a body about which:
Correct Answer
C. The flow separation is suppressed
Explanation
A streamlined body refers to a body in which the flow separation is suppressed. This means that the flow of fluid over the body remains attached and does not separate, which helps in reducing drag. In a streamlined body, the flow remains smooth and follows the streamlines, resulting in laminar flow. However, it does not necessarily mean that the flow is completely laminar or that the drag is zero. The key characteristic of a streamlined body is the suppression of flow separation.
12.
If the area of catchment is 567 km2, then what will be the base width of 3h unit hydrograph, assuming it to be of triangular shape?
Correct Answer
B. 63 hrs
Explanation
The base width of a triangular unit hydrograph is typically determined by the time of concentration, which represents the time it takes for runoff to travel from the furthest point in the catchment to the outlet. The time of concentration is influenced by various factors, including the size and shape of the catchment, the slope of the land, and the type of soil. Without additional information about these factors, it is not possible to accurately determine the base width. Therefore, an explanation for the given correct answer cannot be provided.
13.
If the self purification constant of a large stream flowing with low velocity is 2 and its reoxygenation coefficient is 0.2, then its de oxygenation coefficient will be:
Correct Answer
B. 0.10
Explanation
The deoxygenation coefficient represents the rate at which oxygen is removed from the water. In this case, the self-purification constant is given as 2, which means that the stream can purify itself twice as fast as the oxygen is being removed. The reoxygenation coefficient is given as 0.2, which means that the stream can replenish oxygen at a rate of 0.2 times the rate at which it is being removed. Therefore, the deoxygenation coefficient can be calculated as 1 - (self-purification constant * reoxygenation coefficient) = 1 - (2 * 0.2) = 1 - 0.4 = 0.6. However, this value is not provided in the answer choices. Therefore, the correct answer is 0.10, which is not calculable based on the given information.
14.
Graph between the amount of organic matter left in sewage, and time elapsed in days, is:
Correct Answer
C. Exponential
Explanation
The graph between the amount of organic matter left in sewage and time elapsed in days is exponential. This means that as time increases, the amount of organic matter left in the sewage decreases at an increasing rate. This is because the decay of organic matter follows an exponential decay pattern, where the rate of decay is proportional to the amount of remaining organic matter. As time passes, the remaining organic matter decreases exponentially, leading to a graph that curves downwards.
15.
Reflection cracking is observed in:
Correct Answer
D. Bituminous overlay over cement concrete pavement
Explanation
Reflection cracking is observed in bituminous overlay over cement concrete pavement. This type of cracking occurs when there is a transfer of stress from the underlying concrete pavement to the overlay. The stress is caused by factors such as temperature changes, traffic loads, and shrinkage of the underlying concrete. Over time, the stress leads to the formation of cracks on the surface of the overlay, resembling the pattern of the underlying concrete. This phenomenon is known as reflection cracking and is a common issue in bituminous overlays on cement concrete pavements.
16.
A copper atom is neutral. It's core has a net charge of:
Correct Answer
B. +1
Explanation
A copper atom is neutral, meaning it has an equal number of protons and electrons. Protons have a positive charge, while electrons have a negative charge. Since the atom is neutral, the positive charge of the protons must be balanced by the negative charge of the electrons. Therefore, the net charge of the copper atom's core is 0.
17.
As the temperature of semiconductor is increased:
Correct Answer
B. The average number of free charge carriers increases
Explanation
As the temperature of a semiconductor increases, the average number of free charge carriers increases. This is because at higher temperatures, more electrons gain enough energy to break free from their atomic bonds and become free charge carriers. This increase in free charge carriers leads to a higher conductivity of the semiconductor.
18.
Which of these has the lowest dielectric strength?
Correct Answer
A. Dry air
Explanation
Dry air has the lowest dielectric strength compared to wet air, cotton, and paper. Dielectric strength refers to the ability of a material to withstand an electric field without breaking down and conducting electricity. Dry air has a lower dielectric strength because it contains fewer impurities and moisture compared to wet air, cotton, and paper. These impurities and moisture in wet air, cotton, and paper can increase their dielectric strength, making them better insulators than dry air.
19.
In satellite communication, frequency modulation is used because
satellite channel has:
Correct Answer
B. Large bandwidth and severe noise
Explanation
Frequency modulation is used in satellite communication because it allows for efficient use of a large bandwidth, which is necessary in order to transmit a large amount of data. Additionally, frequency modulation is less susceptible to noise interference compared to other modulation techniques, making it suitable for satellite communication where there is severe noise present.
20.
In communication satellites, the up-link normally operates at a
higher frequency than the down-link because it:
Correct Answer
A. Gives a narrow beam shining into space
Explanation
The up-link operating at a higher frequency than the down-link allows for a narrow beam shining into space. Higher frequencies have shorter wavelengths, which in turn allows for a more focused and directed beam. This narrow beam helps in transmitting the signal more efficiently and accurately towards the satellite.
21.
A transitive dependency is which of the following?
Correct Answer
B. A functional dependency between two or more nonkey attributes
Explanation
A transitive dependency is a functional dependency between two or more nonkey attributes. In other words, it is a situation where the value of one nonkey attribute determines the value of another nonkey attribute, which in turn determines the value of another nonkey attribute. This type of dependency can lead to data redundancy and anomalies in a database, and it is generally desirable to eliminate or minimize transitive dependencies through normalization.
22.
Backward recovery is which of the following?
Correct Answer
A. Where the before-images are applied to the database
Explanation
Backward recovery refers to the process of restoring a database to a previous consistent state by applying the before-images (also known as undo logs) to the database. These before-images contain the changes made to the database and are used to reverse those changes and bring the database back to its previous state. By applying the before-images, any erroneous or incomplete transactions can be rolled back, ensuring data integrity and consistency.
23.
Concurrency control is important for which of the following reasons?
Correct Answer
A. To ensure data integrity when updates occur to the database in a multiuser environment
Explanation
Concurrency control is important to ensure data integrity when updates occur to the database in a multiuser environment. In a multiuser environment, multiple users can access and modify the database simultaneously. Without concurrency control, conflicts may arise when multiple users try to update the same data simultaneously, leading to data inconsistency and loss of data integrity. By implementing concurrency control mechanisms, such as locking or timestamp-based protocols, conflicts can be detected and resolved, ensuring that updates are properly synchronized and data integrity is maintained.
24.
Which of the following refers to associative memory?
Correct Answer
C. There is no need for an address i.e. the data is used as an address
Explanation
Associative memory is a type of computer memory that allows data to be accessed based on its content rather than its physical address. In this type of memory, the data itself serves as the address for retrieval. Therefore, there is no need for a separate address to access the data. This is different from other types of memory where the address of the data is either generated by the CPU or supplied by the users.
25.
A system program that combines the separately compiled modules of a
program into a form suitable for execution.
Correct Answer
B. Limking loader
Explanation
A linking loader is a system program that takes separately compiled modules of a program and combines them into a form that is suitable for execution. It resolves any external references between the modules and generates an executable file that can be loaded into memory and executed. The linking loader performs the necessary linking and relocation operations to ensure that the program can be executed correctly.
26.
Public void test(int x)
{
int odd = 1;
if(odd) /* Line 4 */
{
System.out.println("odd");
}
else
{
System.out.println("even");
}
}
Which statement is true?
Correct Answer
A. Compilation fails.
Explanation
The code will not compile because the if statement at line 4 expects a boolean expression, but the variable "odd" is an integer. To fix this, the if statement should be changed to "if(odd != 0)".
27.
Which of the following is the Language Processor?
Correct Answer
D. All of the above
Explanation
A language processor is a software program or a set of programs that converts human-readable source code into machine-executable code. The given options, "assembler," "compiler," and "interpreter," are all examples of language processors. An assembler converts assembly language code into machine code, a compiler translates high-level programming languages into machine code, and an interpreter executes code directly without prior translation. Therefore, all of the above options are language processors.
28.
Public void test(int x)
{
int odd = 1;
if(odd) /* Line 4 */
{
System.out.println("odd");
}
else
{
System.out.println("even");
}
}
Which statement is true?
Correct Answer
A. Compilation fails.
Explanation
The code will not compile because the if statement expects a boolean condition, but the variable 'odd' is an integer.
29.
The silicon-controlled rectifier can be turned off.
Correct Answer
B. By forced commutation
Explanation
Forced commutation refers to a method of turning off a silicon-controlled rectifier (SCR) by controlling the current flowing through it. This is achieved by applying a reverse voltage across the SCR or by diverting the current away from the SCR using external circuits. By using forced commutation, the SCR can be turned off and the flow of current can be interrupted. Therefore, the correct answer is "by forced commutation."
30.
RTDs are typically connected with other fixed resistors.
Correct Answer
A. In a pi configuration
Explanation
RTDs (Resistance Temperature Detectors) are commonly used in various electrical circuits for temperature measurement. One of the ways to connect RTDs is in a pi configuration. In a pi configuration, three resistors are connected in a specific pattern resembling the Greek letter "π". This configuration helps to compensate for the resistance changes caused by temperature variations, resulting in accurate temperature measurements. Therefore, connecting RTDs in a pi configuration is a common practice in temperature sensing applications.