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Question 1. According to Ohm's Law, if the voltage across a resistor is doubled while resistance remains constant, what happens to the current? A) It halves B) It stays the same C) It doubles D) It quadruples Answer: C Explanation: Ohm's Law states I = V/R. If voltage V doubles and resistance R remains constant, current I also doubles. Question 2. In a series circuit, what is the total resistance? A) The sum of all individual resistances B) The average of all resistances C) The smallest resistance value D) The resistance of the largest resistor Answer: A Explanation: In a series circuit, total resistance is the sum of all individual resistances, R_total = R1 + R2 + R3... Question 3. Which component primarily stores electrical energy in an AC circuit? A) Resistor
B) Inductor C) Capacitor D) Diode Answer: C Explanation: Capacitors store electrical energy in an electric field, and they are used in AC circuits to influence phase and impedance. Question 4. What is the primary purpose of a transformer in an avionics power system? A) Convert AC to DC B) Change voltage levels via electromagnetic induction C) Rectify AC into DC D) Regulate voltage output Answer: B Explanation: Transformers operate based on electromagnetic induction to step voltage up or down, matching impedance and voltage levels. Question 5. Which waveform is characterized by a sine wave with a smooth periodic oscillation? A) Square wave B) Triangle wave C) Sine wave
Explanation: Field-Effect Transistors (FETs) are controlled by voltage at the gate terminal, unlike BJTs which are current-controlled. Question 8. What is the main function of a SCR in an avionics system? A) Amplify signals B) Switch high voltages and currents C) Rectify AC to DC D) Provide voltage regulation Answer: B Explanation: SCRs (Silicon-Controlled Rectifiers) are designed as high-power switches controlled by gate signals, used in switching applications. Question 9. Which logic gate outputs true only when all inputs are true? A) AND B) OR C) NOT D) XOR Answer: A Explanation: The AND gate outputs high only when all inputs are high, performing a logical conjunction.
Question 10. Convert the binary number 1011 to decimal. A) 11 B) 13 C) 9 D) 14 Answer: B Explanation: 1011 in binary equals (1×8)+(0×4)+(1×2)+(1×1)=8+0+2+1=11, so correction: The correct answer is 11, but since 11 is option A, the correct answer is A. Question 11. Which Boolean algebra law states that A + 0 = A? A) Identity law B) Null law C) Complement law D) Distributive law Answer: A Explanation: The identity law states that adding zero to a variable leaves it unchanged: A + 0 = A. Question 12. Which logic family is known for low power consumption and high noise immunity? A) TTL
Answer: B Explanation: Digital-to-Analog Converters (DACs) convert digital signals into corresponding analog voltage or current levels. Question 15. What is the primary function of a resistor color code? A) Indicate power rating B) Show resistance value and tolerance C) Identify component manufacturer D) Specify voltage rating Answer: B Explanation: Color codes on resistors indicate resistance value and tolerance, allowing technicians to identify specifications quickly. Question 16. Which type of capacitor is most suitable for high-frequency filtering? A) Electrolytic B) Ceramic C) Tantalum D) Film Answer: B Explanation: Ceramic capacitors are suitable for high-frequency applications due to their low ESR and good high-frequency characteristics.
Question 17. Which inductor core material typically provides the highest Q factor? A) Air core B) Iron core C) Ferrite core D) Steel core Answer: A Explanation: Air core inductors tend to have higher Q factors because they lack core losses associated with magnetic materials. Question 18. Which device is used for overcurrent protection in aircraft electrical systems? A) Resistor B) Fuse C) Diode D) Transformer Answer: B Explanation: Fuses are designed to protect circuits from overcurrent by melting and breaking the circuit under fault conditions. Question 19. When performing a continuity test with a multimeter, what indicates a good connection?
C) Triangle wave mode D) Pulse mode Answer: B Explanation: Generating a square wave requires selecting the square wave mode on the waveform generator. Question 22. In a spectrum analyzer, what does a peak in the spectrum indicate? A) A signal's dominant frequency component B) Noise level C) Power supply ripple D) Faulty component Answer: A Explanation: Peaks in a spectrum display represent dominant frequency components of the signal being analyzed. Question 23. Which digital circuit component stores a single bit of data? A) Flip-flop B) Register C) Latch D) Bit cell Answer: C
Explanation: A latch is a basic storage element capable of holding one bit; flip- flops are edge-triggered versions. Question 24. Which number system is base-16? A) Binary B) Octal C) Decimal D) Hexadecimal Answer: D Explanation: Hexadecimal is a base-16 numbering system, using digits 0-9 and letters A-F. Question 25. Convert hexadecimal 2F to decimal. A) 47 B) 59 C) 45 D) 69 Answer: A Explanation: 2F in hex = (2×16) + 15 = 32 + 15 = 47 decimal. Question 26. Which logic gate performs the inverse of an AND gate?
D) Delta-sigma ADC Answer: B Explanation: Successive approximation ADCs convert analog signals by iteratively approximating the input voltage. Question 29. Which component is used to reduce electromagnetic interference (EMI) in avionics wiring? A) Resistor B) Ferrite bead C) Diode D) Inductor Answer: B Explanation: Ferrite beads suppress high-frequency EMI and RFI in cables and wiring harnesses. Question 30. What does a spectrum analyzer measure? A) Time domain signals B) Voltage over time C) Frequency domain signals D) Resistance Answer: C
Explanation: Spectrum analyzers display signals in the frequency domain, showing amplitude versus frequency. Question 31. Which test equipment is most suitable for measuring the impedance of an antenna? A) Multimeter B) Spectrum analyzer C) LCR meter D) Network analyzer Answer: D Explanation: Network analyzers measure complex impedance over a range of frequencies, ideal for antenna characterization. Question 32. When performing a calibration of a multimeter, what is a key step? A) Use a known reference standard B) Replace the batteries C) Disconnect all leads D) Set to maximum range Answer: A Explanation: Calibration involves comparing measurements to a known standard to ensure accuracy.
B) D-subminiature (D-sub) C) RJ D) All of the above Answer: D Explanation: Various connectors like BNC, D-sub, and RJ45 are used for different avionics applications depending on requirements. Question 36. What is the primary purpose of shielded cable in avionics wiring? A) Reduce weight B) Prevent EMI/RFI interference C) Increase capacitance D) Simplify installation Answer: B Explanation: Shielding reduces electromagnetic interference and radio frequency interference affecting signal integrity. Question 37. Which type of aircraft electrical generator is most commonly used in large commercial aircraft? A) DC generator B) Alternator (AC generator) C) Hand-crank generator
D) Piezoelectric generator Answer: B Explanation: Large aircraft typically use high-capacity AC alternators driven by engines for reliable power generation. Question 38. What does bonding in aircraft wiring ensure? A) Electrical continuity and safety B) Improved signal quality C) Reduced weight D) Increased resistance Answer: A Explanation: Bonding ensures a continuous electrical path, preventing static buildup and ensuring safety. Question 39. Which type of aircraft battery is known for high energy density and longer life? A) Lead-acid B) Nickel-Cadmium (NiCad) C) Lithium-Ion D) Alkaline Answer: C
Question 42. What is the primary concern when handling ESD-sensitive avionics components? A) Overheating B) Static discharge damaging the component C) Moisture absorption D) Mechanical stress Answer: B Explanation: Electrostatic discharge can permanently damage sensitive electronic parts, so proper precautions are essential. Question 43. Which part of the aircraft's pitot-static system measures stagnation pressure to determine airspeed? A) Static port B) Pitot tube C) Altimeter D) VSI Answer: B Explanation: The pitot tube measures stagnation (ram) pressure, which, combined with static pressure, determines airspeed. Question 44. In a typical avionics data bus, what does ARINC 429 specify?
A) Analog signal protocols B) Digital word formats and protocols C) Power supply standards D) Mechanical connector types Answer: B Explanation: ARINC 429 defines digital data transfer protocols, word formats, and electrical standards for avionics. Question 45. What is the main advantage of Ethernet/AFDX in avionics systems? A) Lower cost B) Higher bandwidth and deterministic data transfer C) Simpler wiring D) Compatibility with analog signals Answer: B Explanation: AFDX offers high bandwidth, reliable, and deterministic data transfer suitable for safety-critical avionics. Question 46. Which component is used to switch signals in a multiplexed avionics system? A) Decoder B) Multiplexer
