1.
Most of the solar radiation received on earth surface lies within the range of........
Correct Answer
A. 0.2 to 0.4 microns
Explanation
Solar radiation refers to the energy emitted by the sun in the form of electromagnetic waves. The range of solar radiation received on earth's surface is primarily within the visible light spectrum. This spectrum ranges from approximately 0.38 to 0.78 microns, with the majority of the radiation falling within this range. Therefore, the correct answer is 0.38 to 0.78 microns.
2.
For satellite the source of energy is........
Correct Answer
C. Solar cell
Explanation
Satellites rely on solar cells as their source of energy. Solar cells convert sunlight into electricity, providing a continuous and renewable power source for the satellite. This is essential for the satellite's operation, as it requires energy to power its various systems and instruments while in space. Solar cells are lightweight, durable, and efficient, making them ideal for use in satellite technology. Additionally, they do not require frequent maintenance or refueling, allowing satellites to operate for extended periods without interruption.
3.
The output of solar cell is of the order of........
Correct Answer
A. 1 W
Explanation
The output of a solar cell is typically in the range of 1 watt. Solar cells convert sunlight into electricity through the photovoltaic effect, where photons from the sunlight knock electrons loose from atoms within the cell, generating an electric current. While the output can vary depending on factors such as the size and efficiency of the solar cell, a typical solar cell would produce around 1 watt of power.
4.
Gain of an amplifier = 400, input signal to an amplifier = 0.5 cos (313 t). The output signal is represented as
Correct Answer
A. 20 sin (403 t)
Explanation
The output signal of an amplifier is determined by multiplying the input signal by the gain of the amplifier. In this case, the gain of the amplifier is given as 400. Therefore, the output signal would be 400 * 0.5 cos (313 t) = 200 cos (313 t). However, the given answer is 20 sin (403 t), which is not equal to the calculated output signal. Therefore, the given answer is incorrect and there may be an error in the question or the answer choices.
5.
Microwave energies propagate the length of the waveguide by __________ its side walls.
Correct Answer
A. Refraction off
Explanation
Microwave energies propagate the length of the waveguide by refracting off its side walls. Refraction occurs when a wave changes direction as it passes from one medium to another, in this case from the waveguide to the surrounding air. As the microwaves encounter the walls of the waveguide, they are bent or deflected, allowing them to travel along the length of the waveguide. This refraction phenomenon is essential for the propagation of microwave energies within the waveguide.
6.
Two entities that are combined to form a Magic Tee ar
Correct Answer
B. One H? and one E plane tee
7.
Consider reciprocal of capacitance and torsional spring stiffness as analogous quantities. The system is considered as
Correct Answer
C. Force - voltage
Explanation
In this analogy, the reciprocal of capacitance corresponds to the torsional spring stiffness. Capacitance is a measure of how much charge a capacitor can store per unit voltage, while torsional spring stiffness is a measure of how much torque is required to twist a spring by a certain angle. Both quantities are inversely related to each other. Therefore, the system can be considered as Force - voltage, where force is analogous to torsional spring stiffness and voltage is analogous to the reciprocal of capacitance.
8.
Under mechanical rotational system and electrical system the quantities that are not analogous are
Correct Answer
D. Moment of inertia and conductance
Explanation
Moment of inertia is a property of a rotating object that determines its resistance to changes in its rotational motion, while conductance is a measure of how easily an electric current can flow through a material. These two quantities are not analogous as they belong to different systems - mechanical rotational system and electrical system, respectively.
9.
An ideal current source has zero
Correct Answer
B. Internal conductance
Explanation
An ideal current source has zero internal conductance because it is designed to provide a constant current regardless of the load connected to it. This means that the current source does not have any internal resistance that would cause a drop in voltage or a decrease in current when a load is connected. Therefore, the internal conductance of an ideal current source is zero.
10.
To carry a current of 0.3 amperes, a 100 ohm resistor is needed in an electric circuit. A resistor you would select is
Correct Answer
B. 100 ohm, 10 watts
Explanation
The correct answer is 100 ohm, 10 watts because the power (in watts) can be calculated using the formula P = I^2 * R, where P is power, I is current, and R is resistance. In this case, the current is 0.3 amperes and the resistance is 100 ohms. Plugging these values into the formula, we get P = (0.3)^2 * 100 = 0.09 * 100 = 9 watts. Since the power required is 9 watts, the closest option is 100 ohm, 10 watts.
11.
The vertical distance between the axis of the beam before and after loading at a point is called as
Correct Answer
B. Deflection
Explanation
Deflection refers to the vertical distance between the axis of the beam before and after loading at a specific point. It measures the amount of bending or displacement that occurs in the beam due to the applied load. Deformation, on the other hand, is a more general term that encompasses any change in shape or size of a material under load. Slope is not the correct answer as it refers to the change in the angle of the beam before and after loading, rather than the vertical distance. Therefore, the correct answer for this question is deflection.
12.
The wind intensity can be described by
Correct Answer
C. Beaufort number
Explanation
The Beaufort number is a scale used to estimate wind intensity based on observed effects on land and sea. It ranges from 0 (calm) to 12 (hurricane-force winds). It takes into account factors such as wind speed, wave height, and the behavior of objects in the wind. The Beaufort number is commonly used in weather forecasting and maritime operations to provide a standardized way of describing wind conditions.
13.
Ward-Leonard system of system of speed control is not recommended for
Correct Answer
A. Constant speed operation
Explanation
The Ward-Leonard system of speed control is not recommended for constant speed operation because it is designed to provide adjustable speed control. This system uses a motor-generator set to control the speed of a motor by varying the voltage and frequency. It is ideal for applications that require variable speed control, such as in industrial processes or electric vehicles. However, for constant speed operation, other control methods, such as direct-on-line starting or variable frequency drives, are more suitable and efficient.
14.
Mark the wrong option. Which of the following cause and effect behaviour in speed control is correct when field resistance is increased.
Correct Answer
C. Increase in EMF
Explanation
When the field resistance is increased in a speed control system, it leads to a decrease in the flux. This decrease in flux causes a decrease in the electromotive force (EMF) generated in the system. However, the given answer states that increasing the field resistance causes an increase in EMF, which is incorrect. Therefore, the wrong option is "Increase in EMF."
15.
Small DC motors have best speed control by
Correct Answer
A. Armature voltage control
Explanation
The best speed control for small DC motors is achieved through armature voltage control. By adjusting the voltage applied to the armature, the speed of the motor can be effectively controlled. This method allows for precise speed regulation and is commonly used in applications where accurate speed control is required. Field resistance control and other methods may also be used for speed control, but armature voltage control is considered the most effective for small DC motors.
16.
The short circuit load losses is/are
Correct Answer
A. Direct load loss and stray load losses
Explanation
The correct answer is direct load loss and stray load losses. Short circuit load losses refer to the losses that occur in a power system when a short circuit fault occurs. Direct load loss refers to the losses that occur in the conductors and windings of the electrical equipment due to the flow of current during a short circuit. Stray load losses, on the other hand, refer to the losses that occur in the surrounding components and structures of the electrical equipment due to the magnetic fields generated during a short circuit. Therefore, both direct load loss and stray load losses contribute to the overall short circuit load losses.
17.
The coupling angle or load angle of a synchronous motor is defined as the space angle between
Correct Answer
A. Rotor and stator poles of opposite polarity
Explanation
The coupling angle or load angle of a synchronous motor is defined as the space angle between the rotor and stator poles of opposite polarity. This angle represents the phase difference between the rotor and stator magnetic fields and determines the torque produced by the motor. By measuring the coupling angle, the motor's performance and synchronization with the power system can be evaluated.
18.
Large stiffness coefficient represents
Correct Answer
A. Motor speed remains practically constant
Explanation
A large stiffness coefficient represents that the motor speed remains practically constant. This means that the motor is able to maintain a consistent speed even when subjected to varying mechanical loads. The stiffness coefficient is a measure of how well the motor can resist changes in speed, and a large value indicates a high level of stability in maintaining a constant speed.
19.
Which of the following is/are used in synchronous machines to maintain mechanical stability?
Correct Answer
A. Damper winding
Explanation
The damper winding is used in synchronous machines to maintain mechanical stability. It consists of short-circuited conductors placed in slots on the rotor. When the rotor speed changes, currents are induced in the damper winding, which creates a magnetic field that opposes the change in speed. This helps to dampen any fluctuations and maintain the stability of the machine. The other options, interpole winding, compensating winding, and equalizer rings, are not specifically used for mechanical stability but have other functions in synchronous machines.
20.
Electromagnetic torque is present in rotating machines when
Correct Answer
A. Both stator and rotor windings carry current
Explanation
In rotating machines, electromagnetic torque is generated when both the stator and rotor windings carry current. This is because the interaction between the magnetic fields produced by the currents in the stator and rotor windings creates a torque that causes the rotor to rotate. If only one of the windings carries current, there will not be sufficient interaction between the magnetic fields to generate torque. Therefore, in order for electromagnetic torque to be present, both the stator and rotor windings must carry current.
21.
The operation of a synchronous motor operating on constant excitation across infinite bus will not be stable if power angle δ
Correct Answer
A. Exceeds internal angle θ
Explanation
If the power angle δ exceeds the internal angle θ in a synchronous motor operating on constant excitation across an infinite bus, the operation will not be stable. This means that the motor will not be able to maintain a steady and synchronized rotation with the power system. The power angle represents the phase difference between the rotor and the stator fields, while the internal angle represents the angle between the rotor field and the internal voltage. If the power angle exceeds the internal angle, it indicates that the rotor field is lagging behind the internal voltage, causing instability in the motor's operation.
22.
Who invented the first electricity-generating wind turbine?
Correct Answer
B. Scottish engineer James Blyth
Explanation
Scottish engineer James Blyth is credited with inventing the first electricity-generating wind turbine. In 1887, he built a wind turbine with cloth sails and a dynamo that produced electricity to power his home in Marykirk, Scotland. Blyth's invention marked a significant milestone in renewable energy as it demonstrated the potential of harnessing wind power for electricity generation. His pioneering work laid the foundation for the development of modern wind turbines, which have become a vital source of renewable energy worldwide.
23.
How many blades does a modern wind turbine have?
Correct Answer
A. 3
Explanation
A modern wind turbine typically has three blades. This design is commonly used because it strikes a balance between efficiency and cost-effectiveness. Three blades allow for optimal capture of wind energy while minimizing the weight and cost of the turbine. Additionally, three blades provide stability and reduce noise compared to turbines with more or fewer blades.
24.
Which of these is NOT a part of a modern wind turbine?
Correct Answer
A. Compressor
Explanation
A compressor is not a part of a modern wind turbine. A wind turbine works by converting the kinetic energy of the wind into electrical energy. It consists of several components such as the rotor blades, gearbox, nacelle, and yaw drive. The rotor blades capture the wind's energy and spin the rotor, which is connected to the gearbox. The gearbox increases the rotational speed and transfers the energy to the generator. The nacelle houses the gearbox, generator, and other control systems. The yaw drive allows the turbine to turn and face the wind. However, a compressor is not necessary in a wind turbine as it is used in devices that compress air, such as air conditioners or refrigerators.
25.
How many different components does it take to build a utility scale wind turbine?
Correct Answer
C. More than 8,000
Explanation
A utility scale wind turbine is a complex machine that requires numerous components to function properly. The fact that it takes more than 8,000 components to build a utility scale wind turbine indicates the extensive and intricate nature of its construction. This high number of components highlights the level of precision and engineering involved in creating a wind turbine capable of generating electricity on a large scale.
26.
Roughly how tall are most utility-scale wind turbine towers in the U.S.?
Correct Answer
D. 86 meters (282 feet)
Explanation
Most utility-scale wind turbine towers in the U.S. are roughly 86 meters (282 feet) tall.
27.
What does Heating and cooling of the atmosphere generates?
Correct Answer
C. Convection currents
Explanation
Heating and cooling of the atmosphere generates convection currents. Convection is the transfer of heat through the movement of fluids (in this case, air). When the atmosphere is heated, the air near the surface becomes warmer and less dense, causing it to rise. As the warm air rises, it cools and becomes denser, eventually sinking back down. This creates a continuous cycle of rising and sinking air, known as convection currents. These currents play a crucial role in the redistribution of heat and moisture in the atmosphere, influencing weather patterns and climate.
28.
How much is the energy available in the winds over the earth surface is estimated to be?
Correct Answer
B. 1.6 X 107 MW
Explanation
The estimated energy available in the winds over the earth surface is 1.6 X 107 MW. This means that there is a significant amount of energy that can be harnessed from wind power. Wind turbines can convert the kinetic energy of the wind into electrical energy, and with such a large estimated energy availability, wind power has the potential to be a major source of renewable energy.
29.
How much wind power does India hold?
Correct Answer
A. 20,000 MW
Explanation
India holds 20,000 MW of wind power. This means that India has the capacity to generate 20,000 megawatts of electricity from wind energy sources. Wind power is a significant renewable energy source in India, and the country has been actively investing in and expanding its wind power infrastructure to meet its growing energy demands and reduce its reliance on fossil fuels.
30.
The forces, which meet at one point and their lines of action also lie on the same plane, are known as
Correct Answer
A. Coplaner concurrent forces
Explanation
Coplaner concurrent forces refer to a situation where multiple forces act on an object, meeting at a single point, and their lines of action lie on the same plane. In other words, these forces are in the same plane and their vectors intersect at a common point. This is the correct answer because it accurately describes the scenario where forces are both coplaner (in the same plane) and concurrent (meet at a single point).
31.
Which of the following statement is incorrect?
Correct Answer
D. The velocity ratio of a machine is the ratio of load lifted to the effort applied
Explanation
The velocity ratio of a machine is not the ratio of load lifted to the effort applied. The velocity ratio of a machine is actually the ratio of the distance moved by the effort to the distance moved by the load.
32.
The centre of gravity of a quadrant of a circle lies along its central radius (r) at a distance of?
Correct Answer
B. 0.6r
Explanation
The center of gravity of a quadrant of a circle lies along its central radius at a distance of 0.6r. This can be explained using the concept of symmetry. A quadrant of a circle is a quarter of a circle, and it is symmetrical about its central radius. The center of gravity is the point where the weight of the quadrant is evenly distributed. Since the quadrant is symmetrical, the center of gravity must lie along its central radius. The distance from the center of the circle to the center of gravity is given by 0.6r, which means it is 0.6 times the radius of the circle.
33.
Which of the following are vector quantities?
Correct Answer
D. All of these
Explanation
Angular displacement, angular velocity, and angular acceleration are all vector quantities. A vector quantity is a quantity that has both magnitude and direction. In the case of angular displacement, it represents the change in angle and the direction of rotation. Angular velocity is the rate of change of angular displacement and also has both magnitude and direction. Similarly, angular acceleration is the rate of change of angular velocity and has both magnitude and direction. Therefore, all of these quantities are vector quantities.
34.
Which axial force is determined while analyzing a truss?
Correct Answer
C. Both a. and b.
Explanation
While analyzing a truss, both compressive force and tensile force are determined. This is because a truss is a structure made up of interconnected members, and these members can experience both compressive and tensile forces depending on the loading conditions. Compressive forces act to compress or shorten the members, while tensile forces act to stretch or elongate them. Therefore, both types of forces need to be considered when analyzing a truss.
35.
Work done by an engine in 6 sec is 1000 joules. What is the power generated by the engine in watt?
Correct Answer
D. 166 watt
Explanation
The power generated by an engine can be calculated by dividing the work done by the engine by the time taken. In this case, the work done is given as 1000 joules and the time taken is 6 seconds. Dividing 1000 by 6 gives us approximately 166.67 watts, which can be rounded down to 166 watts. Therefore, the correct answer is 166 watts.
36.
The range of control of controller __________ due to presence of offset.
Correct Answer
B. Decreases
Explanation
The presence of offset in a control system causes the range of control of the controller to decrease. Offset refers to a deviation between the desired setpoint and the actual process variable. When there is offset, the controller needs to continuously adjust its output to try to eliminate the offset. This reduces the effective range of control, as the controller's output is limited by the presence of the offset. Therefore, the correct answer is "decreases".
37.
Shifting of set point and adjusting its new value by the controller, when the value of disturbance increases, is called as_______.
Correct Answer
B. Offset
Explanation
When the value of disturbance increases, the controller adjusts the set point by shifting it and setting a new value. This adjustment is known as offset. It helps to compensate for the disturbance and maintain stability in the system. The other options, set-shift and stabilization, do not accurately describe this process. Therefore, the correct answer is offset.
38.
__________ is a structure made of slender members which are joined together at their end points.
Correct Answer
A. Space Truss
Explanation
A space truss is a structure made of slender members that are joined together at their end points. This type of truss is designed to distribute loads evenly across its members, providing stability and strength. The interconnected members form a three-dimensional framework, allowing for efficient load transfer and resistance to external forces. Space trusses are commonly used in the construction of large-span roofs, bridges, and other structures where strength and stability are crucial.
39.
Find the force in the member RQ.
Correct Answer
B. 450N
Explanation
The force in member RQ is 450N because it is the only option that matches the given answer. Without any additional information or context, it is not possible to determine the force in member RQ based on the given options.
40.
_________ trusses lie on a 3D volume.
Correct Answer
D. 3D
Explanation
Trusses are structural elements that consist of straight members connected at their ends by joints. They are commonly used in construction to support roofs, bridges, and other structures. Trusses can be categorized based on their geometry, and in this case, the question is asking about the type of trusses that lie on a 3D volume. The term "3D" refers to three-dimensional space, indicating that the trusses are not confined to a single plane or surface but extend in all three dimensions. Therefore, the correct answer is "3D."
41.
To design the space trusses which of the following rules is followed?
Correct Answer
B. The loads are applied at the joints
Explanation
In designing space trusses, the loads are applied at the joints. This means that the forces and loads acting on the structure are concentrated at the connection points between the members of the truss. By applying the loads at the joints, it allows for a more efficient distribution of forces throughout the truss system, ensuring that the structure can effectively support the applied loads and maintain its stability.
42.
In a roof supporting space truss, the load is transmitted as:
Correct Answer
A. First to the truss then the joints through purlins
Explanation
In a roof supporting space truss, the load is transmitted first to the truss and then to the joints through purlins. This means that the load is initially borne by the truss members, which distribute the load to the joints. The purlins, which are horizontal beams supported by the truss, then transfer the load from the joints to the rest of the structure. This sequence of load transmission ensures that the load is efficiently distributed and supported throughout the roof truss system.
43.
What is after taking the assumption of the direction of the force in space trusses, the direction comes opposite?
Correct Answer
C. The direction is in the opposite sense, and hence the direction is known to us
Explanation
The correct answer suggests that when the assumption of the direction of the force in space trusses is made, the direction comes out to be opposite. This implies that the assumption made was incorrect and therefore the question cannot be solved further.
44.
When the bridges are extended over long routes or distance then _________
Correct Answer
A. A rocker or a roller is used at the joints
Explanation
When bridges are extended over long routes or distances, a rocker or a roller is used at the joints. This is because long bridges are subject to thermal expansion and contraction, as well as other factors such as wind and traffic loads, which can cause the bridge to move and shift. By using rockers or rollers at the joints, the bridge is able to accommodate these movements and prevent any damage or structural failure. The rockers or rollers allow the bridge to expand and contract freely without putting stress on the structure, ensuring its stability and longevity.
45.
As the loading in bridge different from the simple trusses the calculations involved in the bridges are all 2D calculations.
Correct Answer
B. False
Explanation
The statement is false because the calculations involved in bridges are not limited to 2D calculations. Bridge design and analysis require consideration of various factors such as loads, forces, and structural integrity in both 2D and 3D dimensions. Engineers use advanced software and techniques to model and analyze bridges in three dimensions, taking into account the complex behavior and interactions of different structural elements. Therefore, the calculations involved in bridge design and analysis are not solely limited to 2D.
46.
The emf of the dry cell is about
Correct Answer
D. 1.5 V
Explanation
The emf (electromotive force) of a dry cell is a measure of its ability to provide electrical energy. A higher emf indicates a higher voltage output. In this case, the correct answer is 1.5 V, which means that the dry cell can provide a voltage output of 1.5 volts.
47.
In Daniel cell,
Correct Answer
D. None of these
Explanation
The given options do not accurately describe the characteristics of a Daniel cell. In a Daniel cell, a layer of hydrogen bubbles is not formed, polarization does not take place, and the negative pole is not a copper vessel. Therefore, the correct answer is "None of these."
48.
Secondary’s cells are
Correct Answer
C. Both (a) and (b)
Explanation
Secondary cells are rechargeable batteries that can be used multiple times. They can be discharged and recharged multiple times without losing their capacity. Lead acid cells and alkaline cells are both examples of secondary cells. Lead acid cells are commonly used in automotive applications and are known for their high energy density. Alkaline cells, on the other hand, are commonly used in household devices such as remote controls and flashlights. Therefore, the correct answer is both (a) and (b).
49.
Which of these is not an information based system?
Correct Answer
D. SDS
Explanation
The correct answer is SDS because SDS stands for Software Development System, which is not an information-based system. MIS (Management Information System), DSS (Decision Support System), and SIS (Strategic Information System) are all examples of information-based systems that are used to collect, analyze, and present information to support decision-making processes in organizations. However, SDS is a term used to refer to a system or set of tools used for software development, which is not directly related to information management or decision support.
50.
Which of these factors is not required for communication growth?
Correct Answer
B. Negative atmospHere
Explanation
A negative atmosphere can hinder communication growth. Positive and supportive environments encourage open communication, collaboration, and the exchange of ideas, leading to growth in communication. On the other hand, a negative atmosphere characterized by conflict, distrust, and hostility can create barriers to effective communication, inhibiting growth. Therefore, a negative atmosphere is not required for communication growth.