1.
What is a major difference between a gas and a liquid?
Correct Answer
A. A liquid is far less compressible than a gas.
Explanation
The major difference between a gas and a liquid is their compressibility. A gas can be easily compressed because its particles are far apart and have a lot of empty space between them. On the other hand, a liquid is much less compressible because its particles are closely packed together. Therefore, the correct answer is that a liquid is far less compressible than a gas.
2.
What is the lifting force of a liquid called?
Correct Answer
C. Buoyance.
Explanation
Buoyancy is the correct answer because it refers to the upward force exerted on an object submerged in a fluid, such as a liquid. This force is equal to the weight of the fluid displaced by the object and is responsible for objects floating or sinking in a liquid. Laminar, interface, and dynamic pressure are not related to the lifting force of a liquid.
3.
Which best describes immiscible liquids?
Correct Answer
B. One liquid will float on the other.
Explanation
Immiscible liquids are those that do not mix well together. Instead, one liquid will float on top of the other, forming distinct layers. This occurs because the intermolecular forces between the molecules of the two liquids are not strong enough to overcome the forces of attraction within each individual liquid. As a result, the liquids do not form a homogeneous solution and remain separate.
4.
Which unit of measurement would indicate velocity of flow?
Correct Answer
A. Feet per second
Explanation
The unit of measurement that indicates the velocity of flow is "Feet per second." This unit is commonly used to measure the speed at which a fluid or substance is flowing. It represents the distance traveled in feet divided by the time taken in seconds, giving a measure of how quickly the flow is moving.
5.
Which physical factor affects the behavior of liquids in both rest and motion?
Correct Answer
D. Gravity, atmospHeric pressure, and applied forces.
Explanation
The behavior of liquids in both rest and motion is influenced by gravity, atmospheric pressure, and applied forces. Gravity affects the downward flow of liquids and determines their level in containers. Atmospheric pressure affects the ability of liquids to flow against it, such as in siphoning. Applied forces, such as pushing or pulling, can cause liquids to move or change shape. These three factors work together to determine how liquids behave and interact with their surroundings.
6.
What determines the intensity of the excess pressure in a water-hammer wave?
Correct Answer
D. The amount of extinguished velocity.
Explanation
The intensity of the excess pressure in a water-hammer wave is determined by the amount of extinguished velocity. Water hammer occurs when there is a sudden change in flow velocity, causing a pressure wave to propagate through the pipe. The greater the change in velocity, the more intense the pressure wave will be. Therefore, the amount of extinguished velocity directly affects the intensity of the excess pressure in a water-hammer wave.
7.
Which type of measurement may be used to express pressure?
Correct Answer
D. Pounds per square inch.
Explanation
Pressure is a measure of the force exerted on a surface area. It is commonly expressed in units such as pounds per square inch (psi) because it takes into account both the amount of force (pounds) and the area over which the force is distributed (square inch). Kilograms, pounds, and tons are units of mass, not pressure, so they are not suitable for expressing pressure.
8.
The standard measure for atmospheric pressure is equal to how many pounds per square
inch?
Correct Answer
B. 14.7 psi.
Explanation
The standard measure for atmospheric pressure is commonly known as 1 atmosphere, which is equivalent to 14.7 pounds per square inch (psi). This value represents the average atmospheric pressure at sea level on Earth.
9.
What type of pressure reading is also referred to as overpressure?
Correct Answer
B. Gauge pressure.
Explanation
Gauge pressure is the type of pressure reading that is also referred to as overpressure. Gauge pressure measures the pressure above atmospheric pressure, indicating the amount of pressure exerted by a fluid or gas relative to the surrounding atmospheric pressure. It is commonly used in various applications such as measuring tire pressure, fluid pressure in pipes, or pressure in industrial processes.
10.
What term is used to describe the total pressure acting as a gas?
Correct Answer
C. Absolute pressure.
Explanation
Absolute pressure is the term used to describe the total pressure acting as a gas. It refers to the total pressure exerted by a gas, which includes both the atmospheric pressure and any additional pressure applied. It is measured relative to a perfect vacuum, meaning it includes the pressure of the atmosphere as well. Gauge pressure, on the other hand, only measures the pressure above atmospheric pressure, while atmospheric pressure refers specifically to the pressure exerted by the Earth's atmosphere. Overpressure is not the correct term for describing the total pressure acting as a gas.
11.
Which temperature scale is commonly used for scientific measurements?
Correct Answer
A. Kelvin scale.
Explanation
The Kelvin scale is commonly used for scientific measurements because it is an absolute temperature scale that starts at absolute zero, the point at which all molecular motion ceases. This makes it ideal for scientific calculations and experiments as it allows for precise measurements and comparisons of temperature. The other options, Rankine, Réaumur, and Fahrenheit scales, are not commonly used in scientific measurements as they are either based on arbitrary reference points or not widely adopted.
12.
Which gas law declares that cooling a gas decreases its volume?
Correct Answer
B. Charles’ law.
Explanation
Charles' law states that the volume of a gas is directly proportional to its temperature, assuming that the pressure and amount of gas remain constant. According to this law, as the temperature of a gas decreases, its volume will also decrease. Therefore, Charles' law explains why cooling a gas decreases its volume.
13.
Two or more atoms combined is called a
Correct Answer
C. A molecule.
Explanation
When two or more atoms combine, they form a molecule. A molecule is a group of atoms held together by chemical bonds. In this case, the question is asking for the term used to describe the combination of atoms, and the correct answer is "a molecule." A compound refers to a substance composed of two or more different elements, while an element is a pure substance made up of only one type of atom. A mixture, on the other hand, is a combination of two or more substances that are not chemically bonded.
14.
According to the electron theory, atoms are composed of
Correct Answer
A. Protons, neutrons, and electrons.
Explanation
The electron theory states that atoms are composed of protons, neutrons, and electrons. Protons are positively charged particles found in the nucleus of an atom, while neutrons are neutral particles also located in the nucleus. Electrons are negatively charged particles that orbit the nucleus. This theory suggests that atoms are made up of these three fundamental particles. The other options in the question do not accurately represent the composition of atoms according to the electron theory.
15.
How do the charges of protons and electrons differ?
Correct Answer
D. Protons have positive charges, and electrons have negative charges.
Explanation
Protons and electrons have opposite charges. Protons have a positive charge, while electrons have a negative charge. This is a fundamental property of these particles in the atomic structure.
16.
The uniform movement of electrons in a specific direction is called
Correct Answer
C. Electric current.
Explanation
The correct answer is electric current. Electric current refers to the uniform movement of electrons in a specific direction. It is the flow of electric charge through a conductor, such as a wire. This movement of electrons creates a flow of energy, which is the basis for various electrical phenomena and devices. Electrical potential, free electrons, and ionization are related concepts but do not specifically refer to the uniform movement of electrons in a specific direction as electric current does.
17.
Which shell of the valence electrons determines whether a material is a good or a poor
conductor of electricity?
Correct Answer
A. The outermost shell.
Explanation
The outermost shell of valence electrons determines whether a material is a good or a poor conductor of electricity. This is because the outermost shell is responsible for the bonding and interaction between atoms, which affects the material's ability to conduct electricity. If the outermost shell is filled or tightly bound, the material is likely a poor conductor. However, if the outermost shell is not filled or loosely bound, the material is more likely to be a good conductor of electricity.
18.
Which statement best describes a positive ion?
Correct Answer
B. An atom that lost an electron and has more protons.
Explanation
A positive ion is formed when an atom loses one or more electrons. This results in an imbalance of positive protons and negative electrons, causing the atom to have a net positive charge. Therefore, the statement "An atom that lost an electron and has more protons" best describes a positive ion.
19.
What effect of current causes an electric motor to produce mechanical energy?
Correct Answer
B. Magnetism.
Explanation
When an electric current flows through the coils of an electric motor, it creates a magnetic field. This magnetic field interacts with the permanent magnets within the motor, causing the rotor to spin and producing mechanical energy. Therefore, the effect of current that causes an electric motor to produce mechanical energy is magnetism.
20.
What is the unit of measurement for electrical power?
Correct Answer
A. Watts.
Explanation
The unit of measurement for electrical power is watts. Watts measure the rate at which electrical energy is transferred or used per unit of time. It is named after James Watt, a Scottish inventor who made significant contributions to the development of the steam engine. Watts are commonly used to measure the power output of electrical devices and the consumption of electricity in homes and businesses.
21.
A 3-horsepower motor consumes how much power?
Correct Answer
D. 2,238 W.
Explanation
The correct answer is 2,238 W because 1 horsepower is equal to 745.7 watts. Therefore, a 3-horsepower motor would consume 3 times that amount, which is 2,237.1 watts. Rounded to the nearest whole number, the answer is 2,238 W.
22.
A magnet that is magnetized by induction from an external source is called
Correct Answer
C. An artificial magnet.
Explanation
An artificial magnet is a magnet that is magnetized by induction from an external source. This means that the magnet does not have inherent magnetic properties but acquires them through the influence of an external magnetic field. Unlike natural magnets, which occur naturally in the form of minerals like magnetite, artificial magnets are man-made and can be created using materials like iron or steel. Therefore, the correct answer is an artificial magnet.
23.
When do the magnetic lines of force in a magnet cross?
Correct Answer
D. Magnetic lines of force never cross each other.
Explanation
Magnetic lines of force never cross each other because they represent the direction of the magnetic field. If they were to cross, it would imply that the magnetic field has two different directions at the same point, which is not possible. The lines always flow from the north pole to the south pole of a magnet, and they do not intersect or cross each other.
24.
What are the two most common methods of producing voltage?
Correct Answer
C. Chemical and mechanical.
Explanation
The correct answer is chemical and mechanical because voltage can be produced through chemical reactions, such as in batteries, where chemical energy is converted into electrical energy. Voltage can also be produced through mechanical methods, such as in generators, where mechanical energy is converted into electrical energy through the motion of a magnet within a coil of wire.
25.
What type of current flow is the result of voltages produced by batteries and
thermocouples?
Correct Answer
B. Direct current.
Explanation
The correct answer is direct current. Direct current (DC) is the type of current flow that is produced by batteries and thermocouples. DC flows in only one direction and has a constant magnitude. It is commonly used in electronic devices and systems that require a steady and consistent flow of current.
26.
What type(s) of current flow cannot be transformed from a higher voltage to a lower
voltage?
Correct Answer
B. Direct current.
Explanation
Direct current cannot be transformed from a higher voltage to a lower voltage. This is because direct current flows in only one direction and does not change its polarity over time. Therefore, it cannot be easily stepped down or transformed to a lower voltage like alternating current, which can be easily transformed using transformers.
27.
What are the three things needed to produce voltage by the principle of electromagnetic
induction?
Correct Answer
D. Magnetic field, conductor, and relative motion.
Explanation
To produce voltage by the principle of electromagnetic induction, three things are required: a magnetic field, a conductor, and relative motion between the magnetic field and the conductor. The magnetic field provides the force necessary for the induction process, the conductor allows for the flow of electrons, and the relative motion between the two creates a change in the magnetic field, inducing a voltage in the conductor. The other options mentioned do not accurately describe the necessary components for electromagnetic induction.
28.
What type of material is used to construct the fuel tank on the R–11?
Correct Answer
C. Sheet aluminum alloy.
Explanation
The correct answer is sheet aluminum alloy. This type of material is commonly used to construct fuel tanks in aircraft due to its lightweight and corrosion-resistant properties. Aluminum alloys are strong and durable, making them suitable for containing and storing fuel safely. Additionally, sheet aluminum alloy can be easily formed and welded, allowing for the construction of complex shapes and designs required for fuel tanks.
29.
Which is not a type of positive displacement pump?
Correct Answer
D. Centrifugal.
Explanation
The question asks for a type of positive displacement pump that is not included in the options. The options provided are gear, piston, and rotary. These are all types of positive displacement pumps, as they use a mechanism to displace a fixed amount of fluid with each cycle. However, centrifugal pumps are not positive displacement pumps. They work by using centrifugal force to increase the fluid's velocity and then convert it into pressure. Therefore, the correct answer is centrifugal.
30.
What term is used to define the process that takes place when water forms into droplets after
passing through filter elements?
Correct Answer
C. Coalescing.
Explanation
Coalescing is the term used to define the process that takes place when water forms into droplets after passing through filter elements. Coalescing refers to the merging or coming together of smaller droplets to form larger droplets. In this context, it describes the process of water droplets combining or coalescing into larger droplets as they pass through the filter elements. This helps to separate the water from any impurities or contaminants present in the filtration system.
31.
What filter separator component prevents pressure surges from damaging dispensing
pressure control systems?
Correct Answer
A. Air eliminator.
Explanation
An air eliminator is a filter separator component that is designed to remove air or gas from a liquid flow. It prevents pressure surges by eliminating air pockets or bubbles that can cause fluctuations in pressure. By removing air, the air eliminator ensures a consistent and stable flow of liquid, protecting the dispensing pressure control systems from any damage that could be caused by sudden pressure changes.
32.
What type of meter is used on most fuel dispensing systems?
Correct Answer
B. Bi-rotor, positive displacement.
Explanation
Bi-rotor, positive displacement meters are commonly used on most fuel dispensing systems. These meters work by measuring the volume of fuel passing through the system. The bi-rotor design consists of two rotors that rotate in opposite directions, creating chambers that fill and empty as the fuel flows through. This design ensures accurate measurement of the fuel volume, making it an ideal choice for fuel dispensing systems where precise measurement is crucial. Positive displacement meters are known for their reliability and accuracy, making them the preferred choice in the industry.
33.
What item protects fuel dispensing system electrical components against overload?
Correct Answer
A. Automatic reset-type circuit breakers.
Explanation
Automatic reset-type circuit breakers protect fuel dispensing system electrical components against overload. These circuit breakers automatically trip and then reset themselves when they detect excessive current flow, preventing damage to the electrical components. This ensures the safety and proper functioning of the fuel dispensing system by preventing overload situations that could lead to electrical failures or fires. Manual reset-type circuit breakers require manual intervention to reset after tripping, while the mentioned fuses do not provide the automatic reset feature.
34.
What type of lubricant is used to lubricate the power takeoff (PTO) on a fuel dispensing
system?
Correct Answer
B. Ninety-weight gear oil.
Explanation
Ninety-weight gear oil is the correct answer for lubricating the power takeoff (PTO) on a fuel dispensing system. Gear oil is specifically designed to lubricate gears and other high-pressure components, making it suitable for the PTO mechanism. The "ninety-weight" refers to the viscosity of the oil, indicating its thickness and ability to withstand high temperatures and heavy loads. This type of lubricant ensures smooth operation and reduces friction, extending the lifespan of the PTO system.
35.
What component found on R–11s and R–12s prevents the auxiliary throttle from operating
unless the power takeoff (PTO) is engaged?
Correct Answer
B. Throttle interlock system.
Explanation
The throttle interlock system is the component found on R-11s and R-12s that prevents the auxiliary throttle from operating unless the power takeoff (PTO) is engaged. This system ensures that the auxiliary throttle can only be used when the PTO is active, adding an extra layer of safety and preventing accidental throttle operation.
36.
What fuel dispensing system component controls system fuel pressure?
Correct Answer
A. Bypass system.
Explanation
The bypass system is responsible for controlling the fuel pressure in the fuel dispensing system. It allows excess fuel to bypass the mainline system, regulating the pressure and ensuring that it remains within the desired range. This component is crucial in maintaining the proper functioning of the fuel dispensing system and preventing any potential damage or malfunctions.
37.
During bottom loading operations, what occurs when the signal to the bottom loading optic
probe is lost?
Correct Answer
D. The electronic control module cuts power to the bottom loading electric air solenoid.
Explanation
When the signal to the bottom loading optic probe is lost, the electronic control module cuts power to the bottom loading electric air solenoid. This means that the solenoid, which controls the flow of air to the bottom loading valve, will no longer receive power and will be deactivated. This action is taken to prevent any further flow of product during the loading operation, ensuring safety and preventing any potential accidents or spills.
38.
When should Bourdon gauges be calibrated?
Correct Answer
C. Annually.
Explanation
Bourdon gauges should be calibrated annually. Calibrating these gauges on a yearly basis ensures that they continue to provide accurate measurements. Regular calibration helps to identify any deviations or inaccuracies in the gauge's readings, allowing for adjustments or repairs to be made as necessary. This ensures the reliability and precision of the gauge's measurements, which is crucial in various industries where Bourdon gauges are commonly used, such as oil and gas, manufacturing, and HVAC.
39.
What may a filter separator differential pressure reading below 3 pounds per square inch
(psi) indicate?
Correct Answer
D. A defective O-ring or ruptured coalescers.
Explanation
A filter separator differential pressure reading below 3 psi may indicate a defective O-ring or ruptured coalescers. This is because a low differential pressure suggests that there is not enough resistance or obstruction in the system, which could be caused by a faulty O-ring or ruptured coalescers.
40.
When performing meter calibrations, what is the acceptable difference between the master
meter and the meter being calibrated?
Correct Answer
A. ½ gallon for each 100 gallons passing through the meter.
Explanation
The acceptable difference between the master meter and the meter being calibrated is ½ gallon for each 100 gallons passing through the meter. This means that for every 100 gallons that pass through the meter being calibrated, there can be a difference of up to ½ gallon compared to the master meter. This allows for a small margin of error in the calibration process.
41.
Initial tool listings for individual tool kits (ITK) and composite tool kits (CTK) include all
of the following except
Correct Answer
B. Quantity on hand.
Explanation
The initial tool listings for individual tool kits (ITK) and composite tool kits (CTK) include nomenclature, quantity authorized, and tool national stock number (NSN). However, the quantity on hand is not included in the initial tool listings. This means that the listings do not provide information about how many of each tool are currently available.
42.
How often should joint inventories for all individual tool kits (ITK) be accomplished?
Correct Answer
D. Annually.
Explanation
The correct answer is Annually. Joint inventories for all individual tool kits (ITK) should be accomplished once a year. This means that all the tools in the tool kits should be counted and checked for any missing or damaged items on an annual basis. This helps ensure that the tool kits are properly maintained and that any necessary repairs or replacements can be made in a timely manner. Regular inventories also help prevent any tools from being lost or misplaced, which can save time and money in the long run.
43.
What type of time compliance technical order (TCTO) is issued for safety conditions which,
if left uncorrected, could result in fatality or serious injury to personnel or extensive damage to or
destruction of valuable property?
Correct Answer
D. Immediate action.
Explanation
Immediate action is the correct answer because it refers to a type of time compliance technical order (TCTO) that is issued for safety conditions that, if not corrected immediately, could result in fatal or serious injuries to personnel or significant damage to valuable property. This type of TCTO requires immediate attention and corrective action to prevent any potential harm or damage.
44.
Urgent action time compliance technical orders (TCTO) require compliance within what
maximum amount of days?
Correct Answer
A. 10 days.
Explanation
Urgent action time compliance technical orders (TCTO) are time-sensitive directives that require immediate attention and compliance. These orders are issued to address critical safety or operational issues. In this case, the correct answer is 10 days, which means that the personnel must comply with the TCTO within a maximum of 10 days from the issuance. This emphasizes the urgency and importance of addressing the specified issue promptly to ensure safety and operational effectiveness.
45.
Which publication is a memorandum issued by commercial manufacturers advising
maintainers of minor defects with a product?
Correct Answer
B. Service bulletin.
Explanation
A service bulletin is a publication issued by commercial manufacturers to inform maintainers about minor defects with a product. It provides guidance on how to address these issues and ensure the proper functioning of the product. Unlike a TCTO (Time Compliance Technical Order) which is used for mandatory modifications or repairs, a service bulletin is advisory in nature. A technical manual provides detailed instructions on how to operate or maintain a product, while a manufacturer's recall is a formal request to return or repair a defective product.
46.
What type of publication is issued when a commercial manufacturer discovers dangerous or
unsafe conditions with a product?
Correct Answer
C. Manufacturer’s recall.
Explanation
A manufacturer's recall is issued when a commercial manufacturer discovers dangerous or unsafe conditions with a product. This means that the manufacturer is recalling the product from the market and requesting customers to return it for repair or replacement. This is done to ensure the safety of the consumers and prevent any potential harm or accidents that may occur due to the product's defects.
47.
What type of inspection is performed to determine the condition of a vehicle or piece of
equipment?
Correct Answer
C. Limited technical inspection.
Explanation
A limited technical inspection is performed to determine the condition of a vehicle or piece of equipment. This type of inspection focuses on specific components or systems of the vehicle or equipment, rather than a comprehensive evaluation. It is typically conducted to ensure that the specific components or systems are functioning properly and meet the required standards. Unlike an annual inspection, which covers all aspects of the vehicle or equipment, a limited technical inspection is more targeted and may be performed more frequently to address specific concerns or issues. Preventative maintenance and inspection, on the other hand, refers to routine maintenance and inspection activities aimed at preventing breakdowns and ensuring optimal performance. Special inspection is a vague term and does not provide a clear explanation for determining the condition of a vehicle or equipment.
48.
Within what maximum amount of days of receipt will all new and used vehicles and
equipment be inspected by the Air Force activity which receives it?
Correct Answer
C. 60.
Explanation
The Air Force activity has a maximum of 60 days to inspect all new and used vehicles and equipment after receiving them. This means that they must complete the inspection process within this timeframe to ensure that everything is in working order and meets the necessary standards. If they exceed this deadline, it may cause delays or disruptions in their operations.
49.
What form is used to record limited technical inspections (LTI) on used vehicles?
Correct Answer
C. AFTO Form 91.
Explanation
The correct answer is AFTO Form 91. AFTO Form 91 is used to record limited technical inspections (LTI) on used vehicles. This form is specifically designed for documenting inspections and maintenance actions performed on aerospace vehicles and equipment. It provides a standardized format for recording information such as inspection dates, findings, corrective actions, and inspector's signatures. AFTO Form 91 is an essential tool for maintaining the safety and airworthiness of used vehicles through proper documentation of inspections.
50.
Which of the following may direct shipment of a vehicle with less than 50 percent life
expectancy to satisfy mission requirements?
Correct Answer
C. MAJCOM.
Explanation
The correct answer is MAJCOM. MAJCOM stands for Major Command, which is a level of command in the United States Air Force. They have the authority to make decisions regarding the shipment of vehicles to satisfy mission requirements. The LRS commander, Wing commander, and HQ USAF may not have the same level of authority or jurisdiction to make such decisions.