Module 3 : Electrical Fundamentals

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  • 1/174 Questions

    The relationship between voltage (V), current (I) and resistance (R) for a resistor is:

    • V = IR
    • V = R/I
    • V = IR * R
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About This Quiz

This is only a preparation for EASA Module 3 and not an official EASA exam.

Module 3 : Electrical Fundamentals - Quiz

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  • 2. 

    The process of adding impurities to increase the conductivity of a semiconductor is known as:

    • Doping

    • Expansion

    • Mixture

    Correct Answer
    A. Doping
    Explanation
    Doping is the process of intentionally adding impurities to a semiconductor in order to increase its conductivity. By introducing impurities, either of the same type (known as n-type doping) or of a different type (known as p-type doping), the number of charge carriers in the semiconductor can be increased, thereby enhancing its electrical conductivity. This technique is widely used in the semiconductor industry to modify the properties of semiconductors and create different types of electronic devices.

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  • 3. 

    Which of the following element is known to have one proton and one electron?

    • Hydrogen

    • Germanium

    • Copper

    Correct Answer
    A. Hydrogen
    Explanation
    Hydrogen is known to have one proton and one electron. This is because the atomic number of hydrogen is 1, which indicates the number of protons in its nucleus. The number of electrons in an atom is equal to the number of protons, so hydrogen also has one electron. Germanium and copper have different atomic numbers and therefore different numbers of protons and electrons, making them incorrect options.

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  • 4. 

    What charge does an electron possess?

    • Negative

    • Positive

    • Neutral.

    Correct Answer
    A. Negative
    Explanation
    An electron possesses a negative charge. This is a fundamental property of electrons, which are subatomic particles found in atoms. Electrons have a charge of -1, while protons, which are the other main subatomic particle in atoms, have a positive charge of +1. The negative charge of electrons allows them to be attracted to and orbit around the positively charged nucleus of an atom. This charge difference between electrons and protons is what creates the electrical forces that hold atoms together and allow for the formation of molecules and larger structures.

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  • 5. 

    Which device uses magnetism in generating electricity?

    • Generator

    • Photocell

    • Thermocouple

    Correct Answer
    A. Generator
    Explanation
    A generator is a device that uses magnetism to generate electricity. It consists of a coil of wire that is rotated within a magnetic field. As the coil rotates, the magnetic field induces a current in the wire, generating electricity. This process is known as electromagnetic induction. Therefore, a generator is the correct answer as it utilizes magnetism to produce electrical energy.

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  • 6. 

    Which component uses chemical action in generating electricity?

    • Battery

    • Generator

    • Photocell

    Correct Answer
    A. Battery
    Explanation
    A battery uses chemical action to generate electricity. Inside a battery, there are two electrodes, one positive and one negative, which are immersed in an electrolyte solution. The chemical reactions between the electrodes and the electrolyte produce a flow of electrons, creating an electric current. This chemical reaction continues until the reactants are completely consumed, at which point the battery is discharged and no longer able to generate electricity.

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  • 7. 

    What is the unit of capacitance?

    • Farad

    • Henry

    • Ohms

    Correct Answer
    A. Farad
    Explanation
    The unit of capacitance is the Farad. Capacitance is a measure of the ability of a capacitor to store electrical charge. The Farad is a large unit of capacitance, indicating that the capacitor can store a significant amount of charge. Henry is the unit of inductance, not capacitance. Ohms is the unit of resistance, which is not directly related to capacitance.

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  • 8. 
    Identify the components shown. - ProProfs

    Identify the components shown.

    • Generators

    • Inductors

    • Transformers

    Correct Answer
    A. Transformers
    Explanation
    The components shown in the question are transformers. Transformers are electrical devices that transfer electrical energy between two or more circuits through electromagnetic induction. They consist of two or more coils of wire, known as windings, which are wound around a common magnetic core. Transformers are commonly used in electrical power distribution systems to step up or step down voltage levels, allowing for efficient transmission of electricity over long distances.

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  • 9. 

    What is the phase difference in a 3 phase system?

    • 120 degrees

    • 90 degrees

    • 60 degrees

    Correct Answer
    A. 120 degrees
    Explanation
    In a 3 phase system, the phase difference between each phase is 120 degrees. This means that each phase is offset by 120 degrees from the other phases. This phase difference is important for the proper functioning of the system, as it allows for a balanced distribution of power and helps in generating a rotating magnetic field.

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  • 10. 

    What device is used to measure the specific gravity of a battery electrolyte?

    • Hydrometer

    • Multimeter

    • Oscilloscope.

    Correct Answer
    A. Hydrometer
    Explanation
    A hydrometer is used to measure the specific gravity of a battery electrolyte. Specific gravity refers to the density of a substance compared to the density of water. In the case of a battery electrolyte, the specific gravity indicates the state of charge or the concentration of sulfuric acid in the electrolyte. A hydrometer works by measuring the buoyancy of the electrolyte, which is directly related to its specific gravity. By using a hydrometer, one can determine the health and charge level of a battery.

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  • 11. 

    Which type of capacitor is polarized?

    • Electrolytic

    • Mica

    • Paper

    Correct Answer
    A. Electrolytic
    Explanation
    Electrolytic capacitors are polarized because they have a specific positive and negative terminal. They are designed to operate with a specific polarity, meaning that the voltage applied to them must be in the correct direction. This is due to their construction, which includes an electrolyte solution that can only function properly when the positive and negative terminals are connected correctly. Mica and paper capacitors, on the other hand, are non-polarized and can be connected in either direction without any issues.

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  • 12. 

    Which one of the following gives the angle between the successive phases of a three-phase supply?

    • 60 degrees

    • 90 degrees

    • 120 degrees

    Correct Answer
    A. 120 degrees
    Explanation
    The angle between the successive phases of a three-phase supply is 120 degrees. In a three-phase system, there are three separate phases that are 120 degrees apart from each other. This phase difference allows for a more balanced and efficient distribution of power. Each phase carries its own alternating current waveform, and the 120-degree phase shift ensures that the power is evenly distributed across the three phases, reducing the overall load on the system.

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  • 13. 

    The mutual inductance is increased by increasing the:

    • Number of turns.

    • Distance between the coils.

    • Decreasing the area of the coil.

    Correct Answer
    A. Number of turns.
    Explanation
    The mutual inductance between two coils is directly proportional to the number of turns in each coil. This means that increasing the number of turns in either coil will result in an increase in mutual inductance. This can be explained by the fact that more turns in a coil will result in a stronger magnetic field and thus a stronger magnetic coupling between the two coils, leading to a higher mutual inductance.

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  • 14. 
    The unknown current shown in the figure will be: - ProProfs

    The unknown current shown in the figure will be:

    • 13 A flowing towards the junction

    • 17 A flowing away from the junction

    • 41 A flowing away from the junction

    Correct Answer
    A. 13 A flowing towards the junction
    Explanation
    Based on the given information, the unknown current shown in the figure will be 13 A flowing towards the junction.

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  • 15. 

    "At resonance, the impedance of a series RLC circuit will have the least opposition to current."

    • True

    • False

    Correct Answer
    A. True
    Explanation
    At resonance, the impedance of a series RLC circuit will have the least opposition to current because the reactive components cancel each other out, leaving only the resistance. This means that the circuit is most efficient in allowing current to flow through it.

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  • 16. 

    Which one of the following gives the symbol and abbreviated unit for electrical charge?

    • Symbol, Q ; unit, C

    • Symbol, C ; unit, V

    • Symbol, C ; unit, F

    Correct Answer
    A. Symbol, Q ; unit, C
    Explanation
    The symbol for electrical charge is Q, and the abbreviated unit for electrical charge is C, which stands for coulomb.

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  • 17. 

    A cell that can only be charged once is a:

    • Metal-hydride cell

    • Secondary cell

    • Primary cell

    Correct Answer
    A. Primary cell
    Explanation
    A primary cell is a type of cell that can only be charged once. Once its chemical reaction is complete and the reactants are depleted, it cannot be recharged or reused. This is in contrast to secondary cells, which can be recharged multiple times, and metal-hydride cells, which are a type of secondary cell that use a metal-hydride compound as the active material. Therefore, the correct answer is primary cell.

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  • 18. 

    Battery capacity is measured in:

    • Volts

    • Amperes

    • Ampere-hours

    Correct Answer
    A. Ampere-hours
    Explanation
    Battery capacity is measured in ampere-hours. Ampere-hours (Ah) is a unit that represents the amount of charge a battery can deliver over a specific period of time. It is a product of the current (in amperes) that a battery can supply and the time (in hours) it can sustain that current. This unit is commonly used to determine the energy storage capacity of batteries, as it takes into account both the current and the duration for which the battery can provide that current.

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  • 19. 

    How does increasing the area of the capacitor plate affects capacitance?

    • The capacitance will increase in an increase in area of the plate.

    • The capacitance will decrease in a decrease in area of the plate.

    • Th capacitance is not affected by the area of the plate.

    Correct Answer
    A. The capacitance will increase in an increase in area of the plate.
    Explanation
    The capacitance of a capacitor is directly proportional to the area of the capacitor plate. Therefore, when the area of the plate increases, the capacitance also increases. This is because a larger plate area allows for more electric field lines to be stored, resulting in a higher capacitance.

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  • 20. 

    The eddy current loss in a transformer is reduced by:

    • Laminating the core.

    • Using a material with high reluctance.

    • Increasing the diameter of the conductor.

    Correct Answer
    A. Laminating the core.
    Explanation
    Laminating the core of a transformer reduces eddy current loss. Eddy currents are induced in the core due to the changing magnetic field, which leads to energy loss in the form of heat. By laminating the core, it is divided into thin layers insulated from each other, which helps to restrict the flow of eddy currents and minimize the energy loss. Using a material with high reluctance or increasing the diameter of the conductor may have other benefits in a transformer, but they do not directly address the issue of reducing eddy current loss.

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  • 21. 

    A transformer rated at 500 VA has an iron loss of 3 W and a full load copper loss of 7 W. What is the efficiency of the transformer at 0.8 p.f.?

    • 98 %

    • 0%

    • 100%

    Correct Answer
    A. 98 %
    Explanation
    The efficiency of a transformer can be calculated using the formula:

    Efficiency = (Output Power / Input Power) * 100

    In this case, the output power is the rated VA of the transformer, which is 500 VA. The input power can be calculated by adding the iron loss and the full load copper loss, which is 3 W + 7 W = 10 W.

    Therefore, the efficiency = (500 VA / 10 W) * 100 = 5000 / 10 = 500%.

    Since the efficiency cannot be greater than 100%, the correct answer is 100%.

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  • 22. 

    The charge between two bodies increases when the distance between them is:

    • Decreased.

    • Increased.

    • Unchanged.

    Correct Answer
    A. Decreased.
    Explanation
    When the distance between two bodies decreases, the charge between them increases. This is because the electric force between two charged objects is inversely proportional to the square of the distance between them. As the distance decreases, the force of attraction or repulsion between the charges becomes stronger, resulting in an increase in the charge between the bodies.

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  • 23. 

    An insulator material has:

    • No free charge.

    • Many free charges.

    • Equal number of charges.

    Correct Answer
    A. No free charge.
    Explanation
    An insulator material has no free charge because it does not allow the movement of electrons or ions. Unlike conductors, which have many free charges that can easily move, insulators have tightly bound electrons that are not able to move freely. This lack of free charges in insulators makes them poor conductors of electricity.

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  • 24. 

    The percentage slip is zero in:

    • Synchronous motor.

    • Induction motor.

    • Shunt motor.

    Correct Answer
    A. Synchronous motor.
    Explanation
    The percentage slip is zero in a synchronous motor because it operates at synchronous speed, which means the rotor speed is exactly equal to the stator field speed. This results in no relative motion between the rotor and the stator magnetic fields, causing the slip to be zero. In contrast, both induction motors and shunt motors have a non-zero slip, as they rely on the difference in speed between the rotor and stator fields to induce current and generate torque.

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  • 25. 

    What is the electrolyte in a Lead Acid battery?

    • Sulfuric Acid

    • Potassium Hydroxide

    • Distilled Water

    Correct Answer
    A. Sulfuric Acid
    Explanation
    The electrolyte in a Lead Acid battery is Sulfuric Acid. This is because Sulfuric Acid is a strong acid that can dissociate into ions, allowing for the flow of electric current in the battery. It also helps in the chemical reactions that occur during the charging and discharging of the battery, facilitating the conversion of chemical energy to electrical energy and vice versa. Potassium Hydroxide and Distilled Water are not suitable electrolytes for Lead Acid batteries.

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  • 26. 

    What is an IDG?

    • Integrated Drive Generator

    • Integral Drive Generator

    • Internal Drive Generator

    Correct Answer
    A. Integrated Drive Generator
    Explanation
    An IDG stands for Integrated Drive Generator. This is a device that combines both the generator and the drive mechanism into a single unit. It is commonly used in aerospace applications to provide electrical power to various systems on an aircraft. The integration of the generator and drive mechanism allows for a more compact and efficient design, making it an ideal choice for aircraft where space and weight are critical factors.

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  • 27. 

    Two isolated charges have dissimilar polarities. The force between them will be:

    • A force of attraction

    • A force of repulsion

    • Zero

    Correct Answer
    A. A force of attraction
    Explanation
    Two isolated charges with dissimilar polarities will experience a force of attraction. This is because opposite charges attract each other according to the principle of electrostatics. The charges will exert an attractive force on each other, causing them to move towards each other.

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  • 28. 

    Resistance is ______________ proportional to area of conductor.

    • Inversely.

    • Direct.

    Correct Answer
    A. Inversely.
    Explanation
    Resistance is inversely proportional to the area of the conductor. This means that as the area of the conductor increases, the resistance decreases, and vice versa. This relationship is described by the formula R = ρL/A, where R is the resistance, ρ is the resistivity of the material, L is the length of the conductor, and A is the cross-sectional area. As the area increases, the denominator in the formula becomes larger, resulting in a smaller resistance value. Therefore, resistance and area are inversely related.

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  • 29. 

    Calculate the losses in a transformer if the primary power is 100 kVA and the total power output is 150 KVA.

    • 50 KVA

    • 25 KVA

    • 100 KVA

    Correct Answer
    A. 50 KVA
    Explanation
    The losses in a transformer can be calculated by subtracting the total power output from the primary power. In this case, the primary power is 100 kVA and the total power output is 150 kVA. Therefore, the losses in the transformer would be 50 kVA.

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  • 30. 

    A potential difference of 7.5 V appears across a 15-ohm resistor. Which of the following is the current through the resistor?

    • 0.25 A

    • 0.5 A

    • 2 A

    Correct Answer
    A. 0.5 A
    Explanation
    The potential difference across a resistor is directly proportional to the current flowing through it according to Ohm's Law (V = IR). In this case, a potential difference of 7.5 V is applied across a 15-ohm resistor. To find the current, we can rearrange Ohm's Law to solve for I: I = V/R. Plugging in the values, we get I = 7.5 V / 15 ohms = 0.5 A. Therefore, the correct answer is 0.5 A.

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  • 31. 

    What is the unit of true power?

    • Watts

    • VAR

    • VA

    Correct Answer
    A. Watts
    Explanation
    The unit of true power is watts. Watts is a measure of the rate at which energy is transferred or used. It is the product of voltage and current, and represents the actual power consumed or supplied by a device. VAR (volt-ampere reactive) is a unit used to measure reactive power, which is the power that oscillates between the source and load without being consumed. VA (volt-ampere) is a unit used to measure apparent power, which is the vector sum of true power and reactive power. However, in this case, the question specifically asks for the unit of true power, which is watts.

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  • 32. 

    Conventional flow is:

    • Always from negative to positive

    • In the same direction as electron movement

    • In the opposite direction to electron movement

    Correct Answer
    A. In the opposite direction to electron movement
    Explanation
    Conventional flow refers to the direction of current flow in a circuit, which is opposite to the actual movement of electrons. In reality, electrons flow from the negative terminal to the positive terminal of a battery or power source. However, conventional flow is defined as the opposite direction, from positive to negative. This convention was established before the discovery of the electron, and it simplifies circuit analysis and calculations. Therefore, the correct answer is "in the opposite direction to electron movement."

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  • 33. 

    A 28V DC aircraft supply delivers a charge of 5 C to a window heater every second. What is the resistance of the heater?

    • 6 ohms

    • 5.6 ohms

    • 6.2 ohms

    Correct Answer
    A. 5.6 ohms
    Explanation
    The resistance of the heater can be calculated using Ohm's Law, which states that resistance (R) is equal to voltage (V) divided by current (I). In this case, the voltage is 28V and the charge delivered every second is 5C. Since charge (Q) is equal to current multiplied by time (Q = I * t), we can calculate the current as 5C/1s = 5A. Therefore, the resistance is 28V/5A = 5.6 ohms.

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  • 34. 

    In a sine wave, an alternation is defined as:

    • Positive or negative half of the sine wave

    • Positive half of the sine wave

    • Negative half of the sine wave

    Correct Answer
    A. Positive or negative half of the sine wave
    Explanation
    An alternation in a sine wave refers to either the positive or negative half of the wave. This means that when the wave rises above the x-axis, it is considered a positive alternation, and when it falls below the x-axis, it is a negative alternation. Therefore, the correct answer is that an alternation in a sine wave can be either the positive or negative half of the wave.

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  • 35. 

    In an RLC circuit, calculate the total current if the impedance is 20 ohms and connected to a 200 VAC supply.

    • 10 A

    • 0.1 A

    • 20 A

    Correct Answer
    A. 10 A
    Explanation
    The total current in an RLC circuit can be calculated using Ohm's Law, which states that current (I) is equal to voltage (V) divided by impedance (Z). In this case, the impedance is given as 20 ohms and the voltage is given as 200 VAC. Therefore, the total current can be calculated as 200 VAC divided by 20 ohms, which equals 10 A.

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  • 36. 

    If the diameter of a conductor is increased, the resistance will:

    • Decrease.

    • Increase.

    • Not change.

    Correct Answer
    A. Decrease.
    Explanation
    When the diameter of a conductor is increased, the cross-sectional area of the conductor also increases. As resistance is inversely proportional to the cross-sectional area of the conductor, an increase in diameter leads to a decrease in resistance. This is because a larger cross-sectional area allows for more space for the flow of electrons, reducing the likelihood of collisions and increasing the conductivity of the conductor. Therefore, increasing the diameter of a conductor will result in a decrease in resistance.

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  • 37. 

    Connecting battery connected in series will have a higher output:

    • Voltage.

    • Current.

    • Resistance.

    Correct Answer
    A. Voltage.
    Explanation
    When batteries are connected in series, the total voltage output increases. This is because the positive terminal of one battery is connected to the negative terminal of the next battery, creating a cumulative effect. The individual voltages of each battery add up, resulting in a higher overall voltage output. On the other hand, connecting batteries in series does not affect the current or resistance.

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  • 38. 

    In DC circuit, what is Kirchoff's Voltage Law?

    • The sum of the individual voltages are equal to the source.

    • The total voltage will always be higher than any of the resistances.

    • The sum of the voltages is the resultant voltage of all voltages.

    Correct Answer
    A. The sum of the individual voltages are equal to the source.
    Explanation
    Kirchoff's Voltage Law states that in a closed loop in a DC circuit, the algebraic sum of the individual voltages (including voltage drops and voltage rises) is equal to zero. This means that the sum of the voltages across all the components in a closed loop is equal to the total applied voltage or source voltage.

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  • 39. 

    A material having few or no free electron is classified as a good:

    • Insulator.

    • Conductor.

    • Semiconductor.

    Correct Answer
    A. Insulator.
    Explanation
    A material that has few or no free electrons is classified as a good insulator because free electrons are responsible for the flow of electric current in a material. In insulators, the electrons are tightly bound to their atoms and do not move easily, making it difficult for electricity to pass through. Conductors, on the other hand, have a large number of free electrons that can easily move and conduct electricity. Semiconductors have properties in between insulators and conductors, with a moderate number of free electrons.

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  • 40. 
    Referring to the figure, a 20 Ah battery, when discharging at 2 A will be fully discharged at approximately: - ProProfs

    Referring to the figure, a 20 Ah battery, when discharging at 2 A will be fully discharged at approximately:

    • 2 hours

    • 15 minutes

    • 10 hours

    Correct Answer
    A. 10 hours
    Explanation
    Based on the information given, a 20 Ah battery discharging at a rate of 2 A will take approximately 10 hours to fully discharge. This can be calculated by dividing the battery's capacity (20 Ah) by the discharge rate (2 A), which gives us 10 hours.

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  • 41. 

    What device converts the output of a DC generator to DC voltage?

    • Commutator

    • DC Bridge Rectifier

    • Filter

    Correct Answer
    A. Commutator
    Explanation
    The commutator is a device that converts the output of a DC generator to DC voltage. It is a rotating switch that reverses the direction of the current in the generator's coils as they rotate, ensuring that the output voltage remains constant and in the same direction. The commutator plays a crucial role in converting the alternating current (AC) produced by the generator into direct current (DC) that can be used to power various devices.

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  • 42. 

    What is electrical bonding?

    • Connecting the component to the aircraft structure.

    • Connecting the components in series.

    • Connecting the components to a common device.

    Correct Answer
    A. Connecting the component to the aircraft structure.
    Explanation
    Electrical bonding refers to the process of connecting a component to the aircraft structure. This is done to ensure that electrical currents can flow safely and efficiently throughout the aircraft, preventing the buildup of static electricity and reducing the risk of electrical shock or damage. By connecting the component to the aircraft structure, any electrical currents or charges can be properly grounded, creating a safe and reliable electrical system.

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  • 43. 

    A circuits is at resonance if:

    • Inductive reactance is equal to capacitive reactance.

    • The circuit is purely inductive or capacitive.

    • Resistance value is at minimum.

    Correct Answer
    A. Inductive reactance is equal to capacitive reactance.
    Explanation
    At resonance, the inductive reactance and capacitive reactance in a circuit cancel each other out, resulting in a net impedance of zero. This occurs when the frequency of the input signal matches the natural frequency of the circuit. At resonance, the circuit is neither purely inductive nor purely capacitive, as the reactances are balanced. The resistance value does not necessarily have to be at a minimum for the circuit to be at resonance.

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  • 44. 

    Calculate the voltage ratio in a transformer if primary voltage is 20 volts and the secondary supplies 100 volts.

    • 1:5

    • 5:1

    • 2:5

    Correct Answer
    A. 1:5
    Explanation
    The voltage ratio in a transformer is determined by the ratio of the number of turns in the primary winding to the number of turns in the secondary winding. In this case, the primary voltage is 20 volts and the secondary supplies 100 volts, which means that the secondary voltage is 5 times greater than the primary voltage. Therefore, the voltage ratio is 1:5, indicating that for every 1 volt in the primary winding, there are 5 volts in the secondary winding.

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  • 45. 

    In a purely inductive circuit, the current _______ voltage by 90 degrees.

    • Lags

    • Leads

    • Is in phase

    Correct Answer
    A. Lags
    Explanation
    In a purely inductive circuit, the current lags the voltage by 90 degrees. This means that the current waveform reaches its peak value after the voltage waveform has reached its peak. This is because in an inductive circuit, the voltage leads the current due to the presence of inductance. As the voltage across the inductor changes, it induces a back EMF that opposes the change in current, causing the current to lag behind the voltage.

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  • 46. 

    How is the direction of rotation in a 3 phase motor reversed?

    • By reversing 2 of its phases.

    • By reversing at least one phase.

    • By reversing the middle phase.

    Correct Answer
    A. By reversing 2 of its phases.
    Explanation
    The direction of rotation in a 3 phase motor is reversed by reversing 2 of its phases. In a 3 phase motor, the direction of rotation is determined by the sequence of the phase currents. By reversing the connections of any two phases, the phase sequence is altered, resulting in a reversal of the direction of rotation. This can be achieved by swapping the connections of any two of the three phase wires.

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  • 47. 
    Based on the following diagram, is the direction of rotation accurately shown? - ProProfs

    Based on the following diagram, is the direction of rotation accurately shown?

    • Yes. It is clockwise.

    • No. It should be counterclockwise.

    • Yes. But it can also reverse the rotation depending on the value of applied voltage.

    Correct Answer
    A. Yes. It is clockwise.
    Explanation
    The correct answer is Yes. It is clockwise. According to the diagram, the direction of rotation is indicated as clockwise.

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  • 48. 

    The slip speed of an AC induction motor is the difference between:

    • The synchronous speed and the rotor speed

    • The frequency of the supply and the rotor speed

    • The maximum speed and the minimum speed

    Correct Answer
    A. The synchronous speed and the rotor speed
    Explanation
    The slip speed of an AC induction motor is the difference between the synchronous speed and the rotor speed. The synchronous speed is the speed at which the rotating magnetic field of the stator rotates, determined by the frequency of the supply. The rotor speed is the actual speed at which the rotor of the motor is rotating. The slip speed represents the relative speed between the rotating magnetic field and the rotor, which is necessary for the motor to generate torque.

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  • 49. 

    The main aircraft battery is used to start an engine. If the starter demands a current 1000A for 30 sec. and the battery voltage remains at 12V during that period, determine the amount of energy required to start an engine.

    • 100 kJ

    • 360 kJ

    • 420 kJ

    Correct Answer
    A. 360 kJ
    Explanation
    To determine the amount of energy required to start an engine, we can use the formula: Energy = Power x Time. The power can be calculated using the formula: Power = Voltage x Current. Given that the current demanded by the starter is 1000A and the battery voltage remains at 12V for 30 seconds, we can calculate the power as 12V x 1000A = 12000W. Multiplying this power by the time of 30 seconds, we get 12000W x 30s = 360000J, which is equal to 360 kJ. Therefore, the amount of energy required to start the engine is 360 kJ.

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  • Jan 20, 2025
    Quiz Edited by
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  • Jun 26, 2010
    Quiz Created by
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