1.
To Change electrical energy to mechanical energy is the purpose of a
Correct Answer
D. Motor
Explanation
A motor is a device that converts electrical energy into mechanical energy. It does this by using the principle of electromagnetism, where the interaction between electric current and magnetic fields produces a rotational motion. Unlike a generator, which converts mechanical energy into electrical energy, a motor operates in the opposite direction. Therefore, a motor is the correct answer for the given question.
2.
When a motor continues turning after reaching its limit, this is known as
Correct Answer
A. Inertia
Explanation
Inertia refers to the tendency of a motor to continue turning even after it has reached its limit. This is due to the motor's momentum and resistance to changes in its motion. When the motor is powered off or the force causing its rotation is removed, the inertia causes it to keep spinning for a period of time before eventually coming to a stop.
3.
Torque is defined as
Correct Answer
C. Rotational force
Explanation
Torque is defined as rotational force. It is a measure of the force that can cause an object to rotate around an axis. It is commonly used in mechanics and engineering to describe the effectiveness of a force in rotating an object. Torque is dependent on both the magnitude of the force and the distance from the axis of rotation.
4.
In order to operate, a single-phase induction motor requires
Correct Answer
D. A starting system
Explanation
A single-phase induction motor requires a starting system in order to operate. Unlike a three-phase induction motor, a single-phase induction motor cannot start on its own due to the absence of a rotating magnetic field. The starting system provides the necessary initial torque to the motor, allowing it to overcome inertia and start rotating. This can be achieved through various methods such as using a capacitor, a centrifugal switch, or a starting winding. Without a starting system, the motor would not be able to begin its operation.
5.
The difference in the rotor's speed of rotation and the stator magnetic field is known as
Correct Answer
C. Slip
Explanation
Slip refers to the difference in speed between the rotor's rotation and the stator magnetic field in an electric motor. This difference in speed is necessary for the motor to generate torque and effectively convert electrical energy into mechanical energy. Slip is a crucial parameter in motor performance and efficiency, as it directly affects the motor's ability to maintain a stable speed under varying load conditions. Therefore, slip is the correct answer to the question.
6.
Which induction motor has the highest starting torque?
Correct Answer
A. Capacitive start
Explanation
The capacitive start induction motor has the highest starting torque among the given options. This is because the capacitive start motor uses a capacitor in the starting winding to create a phase difference between the main and starting windings. This phase difference results in a higher starting torque compared to other types of induction motors. The squirrel cage, shaded pole, and split phase motors have lower starting torque compared to the capacitive start motor.
7.
The three-phase induction motor does not require
Correct Answer
D. A starting device
Explanation
The three-phase induction motor does not require a starting device because it is a self-starting motor. This is due to the presence of a rotating magnetic field produced by the stator windings. When the motor is powered, the rotating magnetic field induces currents in the rotor, causing it to rotate and start the motor. Therefore, no external starting device is needed to initiate the motor's operation.
8.
The stator windings of a synchronous motor are spaced
Correct Answer
D. 120 degrees apart
Explanation
The stator windings of a synchronous motor are spaced 120 degrees apart. This is because a synchronous motor operates on the principle of magnetic fields rotating at a constant speed. By spacing the stator windings 120 degrees apart, the resulting magnetic fields produced by each winding will also be 120 degrees apart. This allows for a smooth and efficient rotation of the motor's rotor, ensuring synchronous operation.
9.
During an inspection of a direct current (DC) motor, check the brushes for
Correct Answer
B. Seating
Explanation
During an inspection of a DC motor, it is important to check the brushes for seating. Seating refers to the proper alignment and contact of the brushes with the commutator, which is essential for the efficient operation of the motor. If the brushes are not properly seated, it can lead to poor electrical contact, increased friction, and reduced motor performance. Therefore, checking the seating of the brushes ensures that they are in the correct position and making good contact with the commutator.
10.
The first thing you should do when troubleshooting a motor is perform a
Correct Answer
C. Visual inspection
Explanation
A visual inspection is the first thing you should do when troubleshooting a motor because it allows you to visually identify any obvious issues such as loose connections, damaged wires, or burnt components. By inspecting the motor, you can quickly determine if there are any visible signs of damage or malfunction that may be causing the problem. This initial step can help narrow down the possible causes and guide further troubleshooting steps.
11.
In component removal, if wires are to be soldered, do not
Correct Answer
D. Cut them unless there is sufficient length remaining for resoldering
Explanation
When performing component removal and soldering wires, it is important to ensure that the wiring is intact and not damaged. Therefore, the correct approach is to cut the wires only if there is enough length remaining for resoldering. This ensures that the wires can be properly connected and avoids any potential damage or loss of connectivity.
12.
Perform an operational check of the unit
Correct Answer
C. Before final assembly of the enclosure
Explanation
Performing an operational check of the unit before final assembly of the enclosure ensures that the unit is functioning properly and all components are in working order. This step allows for any defects or issues to be identified and resolved before the final assembly, reducing the risk of having to disassemble the enclosure again. By removing the defective part before the operational check, it ensures that the check is accurate and any issues are not caused by the defective part.
13.
What controls the amount of fuel injected when the constant-stroke fuel injection pumps are used?
Correct Answer
B. Control rack
Explanation
The control rack controls the amount of fuel injected when constant-stroke fuel injection pumps are used. The control rack is a mechanical device that regulates the movement of the fuel injectors, determining the amount of fuel that is delivered to the engine. By adjusting the position of the control rack, the operator can control the fuel flow and therefore the engine's power output. This makes the control rack an essential component in managing fuel injection in constant-stroke fuel injection systems.
14.
The constant-stroke pump plunger determines the amount of fuel delivered by the position of a
Correct Answer
C. Helical groove
Explanation
The helical groove in the constant-stroke pump plunger determines the amount of fuel delivered. As the plunger moves up and down, the helical groove allows fuel to flow in and out, controlling the amount of fuel delivered to the engine. The depth and pitch of the groove determine the volume of fuel delivered per stroke. Therefore, the helical groove plays a crucial role in regulating the fuel delivery process in the constant-stroke pump.
15.
What provides the pressure to operate a pressure injector?
Correct Answer
A. Fuel from the fuel system
Explanation
The pressure to operate a pressure injector is provided by the fuel from the fuel system. Pressure injectors are used in various engines, such as gasoline and diesel engines, to deliver fuel into the combustion chamber at high pressure. This high pressure is necessary for efficient fuel atomization and combustion, resulting in optimal engine performance. Therefore, fuel from the fuel system is responsible for generating the required pressure to operate a pressure injector.
16.
Aside from idle speed, the limiting speed governor through the use of flyweights and spring tension controls
Correct Answer
C. Maximum speed
Explanation
The limiting speed governor, using flyweights and spring tension controls, regulates the maximum speed of a system. It ensures that the system does not exceed a certain speed limit, preventing any potential damage or accidents that could occur at higher speeds. This governor is responsible for maintaining the system's stability and safety by keeping the speed within a predetermined maximum range.
17.
What is also reduced when a lubricant reduces friction?
Correct Answer
B. Heat, wear, and resistance
Explanation
When a lubricant reduces friction, it creates a barrier between two surfaces, which reduces the heat generated due to friction. Additionally, the lubricant helps to minimize the wear and tear on the surfaces, reducing the amount of wear. Lastly, by reducing friction, the lubricant also decreases the resistance encountered by the moving parts, allowing for smoother operation.
18.
Which function of a lubricant compensates for microscopic irregularities in the cylinder wall?
Correct Answer
B. Sealing
Explanation
The function of a lubricant that compensates for microscopic irregularities in the cylinder wall is sealing. When a lubricant is applied to the cylinder wall, it forms a thin film that fills in the microscopic gaps and imperfections on the surface. This helps to create a smooth and even surface, reducing friction and preventing metal-to-metal contact. By sealing these irregularities, the lubricant ensures proper lubrication and reduces wear and tear on the engine components.
19.
What component holds a large amount of coolant in close contact with a large volume of air?
Correct Answer
D. Radiator
Explanation
The radiator holds a large amount of coolant in close contact with a large volume of air. As coolant flows through the radiator, it is cooled down by the air passing through the radiator fins. This process helps to dissipate heat from the coolant, preventing the engine from overheating. The radiator is designed to maximize the surface area in contact with the air, allowing for efficient heat transfer. Therefore, the radiator is the component that fulfills the given criteria.
20.
Which liquid cooling system component maintains positive pressure within the cooling system, causes the boiling point of the coolant to be higher, and permits the engine to operate at higher temperature without the coolant boiling?
Correct Answer
C. Radiator cap
Explanation
The radiator cap is the correct answer because it is designed to maintain positive pressure within the cooling system. This pressure increase raises the boiling point of the coolant, allowing the engine to operate at higher temperatures without the coolant boiling. The radiator cap also acts as a seal to prevent coolant from escaping and allows excess pressure to be released through a pressure relief valve.
21.
The purpose of the cooling system thermostat is to maintain correct engine
Correct Answer
A. Operating temperature
Explanation
The purpose of the cooling system thermostat is to maintain the correct operating temperature of the engine. This is important because the engine operates most efficiently and effectively within a specific temperature range. The thermostat helps regulate the flow of coolant through the engine, allowing it to warm up quickly and then maintain a consistent temperature. This prevents the engine from overheating or running too cold, which can cause damage and reduce performance.
22.
What must be accomplished to supercharge a diesel engine?
Correct Answer
B. Change the overlap and timing so that the intake and exhaust valves are open at the same time
Explanation
To supercharge a diesel engine, the overlap and timing of the intake and exhaust valves need to be changed so that they are open at the same time. This allows for better air intake and exhaust flow, increasing the efficiency and power of the engine. By having the intake and exhaust valves open simultaneously, more air can enter the combustion chamber, resulting in improved combustion and increased performance.
23.
The advantage of using a turbocharger on a diesel is the fuel consumption is
Correct Answer
C. Used more efficiently and horsepower is increased
Explanation
A turbocharger on a diesel engine increases the efficiency of fuel usage by compressing the air that enters the engine, allowing more fuel to be burned and producing more power. This increased efficiency leads to improved horsepower output, making the engine more powerful. Therefore, the correct answer is that the fuel is used more efficiently and horsepower is increased.
24.
The maintenance procedure that is considered to be the cheapest and most effective means of reducing injection equipment problems and maintenance costs is
Correct Answer
D. Preventative maintenance
Explanation
Preventative maintenance is the cheapest and most effective means of reducing injection equipment problems and maintenance costs because it involves regularly inspecting and servicing equipment to prevent breakdowns and identify potential issues before they become major problems. This proactive approach helps to avoid costly repairs and downtime, as well as extends the lifespan of the equipment. By regularly performing tasks such as cleaning, lubricating, and replacing worn parts, preventative maintenance ensures that the equipment operates at its optimal level and reduces the likelihood of unexpected failures.
25.
The filtration step protects the diesel engine fuel system from
Correct Answer
D. Abrasion by foreign particles
Explanation
The filtration step in a diesel engine fuel system is designed to prevent the fuel system from being damaged by foreign particles. These particles can cause abrasion, which can lead to wear and tear on the engine components. By filtering out these particles, the fuel system is protected from potential damage and ensures the engine operates smoothly and efficiently.
26.
The first thing you should do when operating a diesel engine is to
Correct Answer
C. Perform a preoperational check
Explanation
Performing a preoperational check is the first thing you should do when operating a diesel engine. This check ensures that all components of the engine are in proper working condition before starting it. It includes inspecting the fuel system, checking for any leaks or damage, examining the engine oil level and quality, inspecting the cooling system, and verifying that all safety devices are functioning correctly. By performing this check, you can identify any potential issues or malfunctions and address them before starting the engine, ensuring safe and efficient operation.
27.
To locate a misfiring cylinder in the diesel engine, use a screw driver to
Correct Answer
B. Hold the injector follower down or closed
Explanation
To locate a misfiring cylinder in a diesel engine, holding the injector follower down or closed with a screwdriver can be effective. By doing so, the fuel supply to that particular cylinder is cut off, causing the engine to run on the remaining cylinders. If the misfiring stops when the injector follower is held down, it indicates that the issue is likely with the fuel injector or its related components in that specific cylinder. This method helps isolate the problematic cylinder and assists in diagnosing and fixing the misfire.
28.
The component that reduces the turbine engine speed fro accessories is the
Correct Answer
A. Gear case
Explanation
The gear case is the component that reduces the turbine engine speed for accessories. It is responsible for transmitting power from the engine to various accessories, such as generators, pumps, and fans, at the appropriate speed. By using gears and other mechanical components, the gear case ensures that the accessories operate at the correct speed for optimal performance and efficiency.
29.
During starting, the turbine engine is rotated up to 20 percent by the
Correct Answer
D. Starter motor
Explanation
The starter motor is responsible for rotating the turbine engine during starting. It provides the initial power needed to start the engine and get it running. The other options mentioned, such as the AC generator, fuel pump and control unit, and tachometer generator, are not directly involved in the starting process of the turbine engine. Therefore, the correct answer is the starter motor.
30.
If the drive shaft for the oil pump assembly in a gas turbine engine becomes sheared, what other component is rendered inoperative?
Correct Answer
B. Tachometer generator
Explanation
If the drive shaft for the oil pump assembly in a gas turbine engine becomes sheared, the tachometer generator is rendered inoperative. The tachometer generator is connected to the drive shaft and relies on its rotation to generate electrical signals that are used to measure the engine's speed. Therefore, if the drive shaft is sheared and no longer rotates, the tachometer generator cannot generate the necessary signals and becomes inoperative.
31.
During gas turbine engine operation, the air is accelerated by the
Correct Answer
C. Impellers
Explanation
Impellers are rotating components in a gas turbine engine that accelerate the air. They consist of a series of blades or vanes that increase the velocity of the air as it passes through them. This increased velocity helps to generate the necessary thrust for the engine to operate efficiently. Diffusers, exducers, and deswirl rings are not directly involved in accelerating the air, making them incorrect options.
32.
The component of the gas turbine engine that causes the air velocity to be reduced, resulting in an increase in pressure, is the
Correct Answer
D. Divergent diffuser
Explanation
The correct answer is divergent diffuser. A divergent diffuser is a component of a gas turbine engine that is responsible for reducing the air velocity and increasing the pressure. It is designed to gradually expand the flow area, allowing the air to slow down and convert its kinetic energy into pressure energy. This process helps to improve the efficiency of the engine by maximizing the pressure difference across the turbine.
33.
During operation of a turbine engine, fuel and air are mixed and ignited in the
Correct Answer
B. Combustor can
Explanation
During the operation of a turbine engine, fuel and air are mixed and ignited in the combustor can. The combustor can is specifically designed to contain the combustion process and allow for efficient fuel burning. It is responsible for providing the necessary conditions for the fuel and air mixture to ignite and produce high-temperature gases, which then flow through the turbine and generate thrust. The combustor can is a critical component in the engine, as it ensures the proper combustion of fuel and air, leading to the efficient operation of the turbine engine.
34.
The boost pump on the gas turbine engine provides fuel to the
Correct Answer
B. Main fuel pump
Explanation
The boost pump on the gas turbine engine provides fuel to the main fuel pump. The main fuel pump is responsible for delivering fuel to the combustion chamber. Therefore, the boost pump plays a crucial role in ensuring that the main fuel pump receives an adequate supply of fuel for combustion.
35.
The two pressure controls in the fuel pump and control unit of the turbine engine are the
Correct Answer
B. Acceleration limiter valve and governor
Explanation
The acceleration limiter valve and governor are the two pressure controls in the fuel pump and control unit of the turbine engine. The acceleration limiter valve regulates the rate at which fuel is delivered to the engine, limiting the acceleration to prevent sudden surges or drops in power. The governor, on the other hand, maintains a constant engine speed by adjusting the fuel flow according to the load demands. Together, these two controls ensure smooth and efficient operation of the turbine engine.
36.
Crack pressure is defined as the amount of
Correct Answer
C. Fuel pressure that is required to overcome spring tension
Explanation
Crack pressure refers to the amount of pressure needed to overcome the spring tension in a system. In this case, the correct answer is "fuel pressure that is required to overcome spring tension." This means that the fuel pressure needs to be sufficient to overcome the tension of the spring in order for the system to function properly.
37.
Which turbine engine fuel system component is normally closed and is energized open when the engine builds up sufficient oil?
Correct Answer
D. Fuel shutoff solenoid valve
Explanation
The fuel shutoff solenoid valve is normally closed and is energized open when the engine builds up sufficient oil. This valve is responsible for controlling the flow of fuel to the engine. When the engine has enough oil pressure, the solenoid valve is opened, allowing fuel to flow into the engine. This ensures that the engine only receives fuel when it is ready to start and prevents any potential damage or accidents.
38.
What types of inputs are used to control the fuel solenoid for the delivery of fuel to the atomizer within the turbine engine fuel system?(418) What types of inputs are used to control the fuel
solenoid for the delivery of fuel to the atomizer within the turbine engine
fuel system?
Correct Answer
D. Air and cooling
Explanation
The fuel solenoid in a turbine engine fuel system is controlled by inputs of air and cooling. These inputs are necessary to regulate the delivery of fuel to the atomizer. Air is required to mix with the fuel for combustion, while cooling is needed to prevent overheating of the fuel system components. Therefore, air and cooling are the types of inputs used to control the fuel solenoid in the turbine engine fuel system.
39.
The turbine engine component that prevents fuel from accumulating in the plenum is the
Correct Answer
B. Drain valve
Explanation
The drain valve is the turbine engine component that prevents fuel from accumulating in the plenum. The plenum is a chamber where air and fuel mix before entering the combustion chamber. If fuel were to accumulate in the plenum, it could cause a rich mixture and potentially lead to engine damage or failure. The drain valve is responsible for removing any excess fuel or other fluids from the plenum, ensuring proper operation and preventing potential hazards.
40.
Lubrication system pressure in the turbine engine is regulated through a
Correct Answer
B. Filter bypass valve
Explanation
The correct answer is the Filter bypass valve. In a turbine engine, the lubrication system pressure needs to be regulated to ensure proper lubrication of the engine components. The filter bypass valve is responsible for regulating the pressure by bypassing the oil filter when the pressure exceeds a certain limit. This prevents damage to the engine and ensures continuous lubrication even if the filter becomes clogged or blocked.
41.
Gas turbine compressor (GTC) operation with insufficient oil pressure is prevented by the
Correct Answer
B. Oil pressure switch
Explanation
The oil pressure switch is responsible for preventing gas turbine compressor (GTC) operation with insufficient oil pressure. This switch acts as a safety mechanism by monitoring the oil pressure and shutting down the GTC if the pressure falls below the required level. By doing so, it ensures that the GTC is not operated without sufficient lubrication, which could lead to damage or failure of the compressor.
42.
The load section of the load control valve consists of chambers
Correct Answer
A. 1 and 2
Explanation
The load section of the load control valve consists of chambers 1 and 2.
43.
The time required to open the load control valve on the turbine engine is controlled by the
Correct Answer
C. Rate adjustment screw
Explanation
The rate adjustment screw is responsible for controlling the time required to open the load control valve on the turbine engine. This screw allows for fine-tuning of the opening rate, ensuring that the valve opens at the desired speed. By adjusting the rate, the engine can effectively manage the flow of air or fuel, optimizing performance and efficiency. The mechanical linkage, actuator diaphragm, and actuator return spring may play a role in the overall operation of the load control valve, but they do not directly control the time required to open it.
44.
If the gas turbine compressor (GTC) load control butterfly valve opens to slowly or too quickly, what is the most probable cause of the malfunction?
Correct Answer
B. Maladjusted rate adjustment screw
Explanation
If the gas turbine compressor (GTC) load control butterfly valve opens too slowly or too quickly, the most probable cause of the malfunction is a maladjusted rate adjustment screw. The rate adjustment screw is responsible for controlling the speed at which the butterfly valve opens and closes. If it is not properly adjusted, it can result in incorrect or inconsistent valve movement, leading to the mentioned malfunction.
45.
In the turbine engine, what prevents rupture of the rate diaphragm?
Correct Answer
A. Adjustment screw
Explanation
The adjustment screw in the turbine engine prevents rupture of the rate diaphragm. It is responsible for controlling the flow of fuel, ensuring that it is at the correct rate. By adjusting the screw, the operator can regulate the fuel flow and prevent excessive pressure or stress on the rate diaphragm, thus avoiding rupture or damage.
46.
During a preoperational inspection of a gas turbine engine, you check the intake and exhaust for
Correct Answer
D. Foreign objects
Explanation
During a preoperational inspection of a gas turbine engine, checking for foreign objects is important because any debris or objects that enter the engine can cause damage to the internal components. Foreign objects can obstruct the airflow, leading to reduced engine performance or even complete engine failure. Therefore, it is crucial to ensure that the intake and exhaust are free from any foreign objects to maintain the engine's efficiency and prevent potential damage.
47.
Normal acceleration characteristics of the gas turbine compressor (GTC) include
Correct Answer
B. A decrease in vibration after 35 percent
Explanation
The correct answer is a decrease in vibration after 35 percent. This means that the gas turbine compressor (GTC) experiences a decrease in vibrations as it accelerates, specifically after it reaches 35 percent of its maximum speed. This characteristic indicates that the GTC is operating smoothly and quietly during acceleration.
48.
Common or frequently occurring troubles in a unit, their cause, and remedies may be found in the
Correct Answer
C. Troubleshooting chart
Explanation
A troubleshooting chart is a resource that provides information on common or frequently occurring troubles in a unit, their cause, and remedies. It is a useful tool for identifying and resolving issues in a systematic manner. The historical record may provide information on past issues, but it may not have the specific cause and remedy details needed. The maintenance record is focused on documenting maintenance activities rather than troubleshooting. The illustrated parts breakdown is a visual representation of the unit's components and may not provide troubleshooting information. Therefore, the best option for finding information on common troubles, their cause, and remedies is the troubleshooting chart.
49.
If no oil pressure is available from the main oil pump assembly on the gas turbine compressor (GTC), what should you replace?
Correct Answer
B. Entire assembly
Explanation
If no oil pressure is available from the main oil pump assembly on the gas turbine compressor (GTC), the most appropriate course of action would be to replace the entire assembly. This is because if there is no oil pressure, it indicates a failure or malfunction in the pump assembly as a whole, rather than a specific component such as the flow check valve or filter bypass relief valve. By replacing the entire assembly, it ensures that all components are functioning properly and can restore the necessary oil pressure for the GTC.
50.
Which causes gray or white smoke to pour from the exhaust stack on the gas turbine compressor (GTC)?
Correct Answer
C. Oil that enters the airflow system
Explanation
When oil enters the airflow system of a gas turbine compressor (GTC), it causes gray or white smoke to pour from the exhaust stack. This occurs because the oil mixes with the airflow and is burned during the combustion process. As a result, the smoke is emitted through the exhaust, indicating the presence of oil in the system. Excessive engine revolutions per minute (rpm) and engine exhaust temperature may cause other issues, but they do not directly cause smoke to pour from the exhaust stack.