Electronic Systems MCQs December 4, 2025August 23, 2024 by u930973931_answers 50 min Score: 0 Attempted: 0/50 Subscribe 1. What is the primary function of a transistor in electronic circuits? (A) To store electrical energy (B) To measure voltage (C) To convert AC to DC (D) To amplify or switch electronic signals 2. Which type of transistor is known for having three layers of semiconductor material? (A) MOSFET (B) IGBT (C) JFET (D) BJT 3. What does the acronym MOSFET stand for? (A) Metal-Oxide-Superior Field-Effect Transistor (B) Metal-Oxide-Silicon Field-Effect Transistor (C) Metal-Oxide-Semiconductor Field-Effect Transistor (D) Metal-Organic-Semiconductor Field-Effect Transistor 4. Which component is used to filter out noise in a signal? (A) Diode (B) Resistor (C) Inductor (D) Capacitor 5. What is the purpose of a diode in an electronic circuit? (A) To amplify signals (B) To store electrical energy (C) To allow current to flow in one direction only (D) To vary resistance 6. In which type of semiconductor device is the current controlled by an electric field? (A) BJT (B) Diode (C) MOSFET (D) Resistor 7. Which of the following is used to increase the impedance of a signal in an electronic circuit? (A) Inductor (B) Capacitor (C) Transformer (D) Resistor 8. What is the main function of an operational amplifier (op-amp)? (A) To act as a voltage regulator (B) To store charge (C) To amplify weak electrical signals (D) To convert AC to DC 9. Which type of circuit is used to convert a varying input signal to a stable output signal? (A) Oscillator (B) Amplifier (C) Filter (D) Voltage regulator 10. What is the unit of capacitance? (A) Ohm (B) Volt (C) Henry (D) Farad 11. Which component provides a controlled variable resistance in an electronic circuit? (A) Potentiometer (B) Diode (C) Capacitor (D) Transformer 12. What does the term “biasing” refer to in transistor circuits? (A) Changing the signal frequency (B) Increasing the current gain (C) Decreasing the power dissipation (D) Setting the operating point of the transistor 13. In digital electronics, what does the term “logic gate” refer to? (A) A device that performs arithmetic operations (B) A device that performs logical operations on binary inputs (C) A device that processes analog signals (D) A device that amplifies analog signals 14. Which logic gate outputs a true value only when both inputs are true? (A) AND gate (B) NAND gate (C) OR gate (D) XOR gate 15. What is the main function of a Schmitt trigger? (A) To amplify analog signals (B) To convert AC to DC (C) To provide a stable digital output from noisy input signals (D) To filter high-frequency noise 16. Which component is used to store electrical energy in a magnetic field? (A) Capacitor (B) Resistor (C) Transformer (D) Inductor 17. In a bipolar junction transistor (BJT), what are the three regions called? (A) Source, Drain, Gate (B) Emitter, Collector, Base (C) Anode, Cathode, Gate (D) Collector, Base, Gate 18. What type of transistor is known for having high input impedance and low output impedance? (A) MOSFET (B) JFET (C) BJT (D) IGBT 19. What is the typical operating voltage range for most logic ICs in digital circuits? (A) 5V to 12V (B) 1.5V to 3V (C) 12V to 24V (D) 24V to 48V 20. Which type of electronic component is used to convert light signals into electrical signals? (A) Photodiode (B) LED (C) Transistor (D) Capacitor 21. What is the function of a logic level shifter? (A) To increase the voltage level of digital signals (B) To decrease the current level of digital signals (C) To convert digital signals from one voltage level to another (D) To convert analog signals to digital 22. Which component is used to protect circuits from voltage spikes? (A) Capacitor (B) Inductor (C) Zener diode (D) Resistor 23. What does the term “frequency response” refer to in electronic systems? (A) The rate at which a component stores charge (B) The rate at which a component changes resistance (C) The rate at which a component amplifies signals (D) The range of frequencies over which a component or circuit operates effectively 24. What is the primary function of an oscillator in electronic circuits? (A) To convert DC to AC (B) To store electrical energy (C) To amplify weak signals (D) To generate periodic signals 25. Which component is used in electronic circuits to store and release electrical energy in the form of a charge? (A) Capacitor (B) Resistor (C) Inductor (D) Transformer 26. What is the main purpose of a rectifier circuit? (A) To convert AC voltage to DC voltage (B) To amplify AC signals (C) To filter high-frequency noise (D) To generate high-frequency signals 27. Which type of diode is specifically designed for high-frequency applications? (A) Zener diode (B) Schottky diode (C) Light-emitting diode (LED) (D) Photodiode 28. What is the purpose of a power amplifier in an electronic system? (A) To reduce signal strength (B) To increase signal strength (C) To filter out unwanted frequencies (D) To convert AC signals to DC signals 29. Which electronic component is used to regulate voltage in a circuit? (A) Voltage regulator (B) Transformer (C) Capacitor (D) Inductor 30. What does the term “pulse width modulation” (PWM) refer to? (A) The modulation of signal amplitude (B) The modulation of signal frequency (C) The modulation of signal phase (D) The modulation of signal width or duration 31. Which device is used to convert an analog signal into a digital signal? (A) Digital-to-Analog Converter (DAC) (B) Operational Amplifier (C) Analog-to-Digital Converter (ADC) (D) Voltage Regulator 32. What is the function of a differential amplifier in electronic systems? (A) To amplify the sum of two input signals (B) To filter out noise from a signal (C) To amplify the difference between two input signals (D) To convert AC signals to DC 33. Which of the following components is commonly used to provide feedback in amplifiers? (A) Resistor (B) Capacitor (C) Inductor (D) Diode 34. In digital circuits, what does the term “clock signal” refer to? (A) A signal that determines the timing of operations (B) A signal that filters high-frequency noise (C) A signal used to measure current (D) A signal that regulates voltage 35. Which type of transistor is commonly used for switching applications due to its low on-resistance? (A) BJT (B) IGBT (C) JFET (D) MOSFET 36. What is the primary purpose of an LED in electronic circuits? (A) To store electrical energy (B) To filter noise (C) To regulate voltage (D) To provide visual indication 37. What does the term “bandwidth” refer to in electronic systems? (A) The size of an electronic component (B) The amount of power a circuit can handle (C) The rate at which a component stores charge (D) The range of frequencies a circuit can operate over 38. Which component is used to smooth out the output of a rectifier circuit? (A) Capacitor (B) Inductor (C) Transformer (D) Resistor 39. What does the term “gain” refer to in an amplifier? (A) The ability to store energy (B) The ability to increase signal amplitude (C) The ability to decrease signal frequency (D) The ability to filter noise 40. Which component is used to adjust the frequency of an oscillator circuit? (A) Capacitor (B) Inductor (C) Resistor (D) Diode 41. In digital systems, what does the term “binary” mean? (A) A system that uses decimal numbers (B) A system that uses hexadecimal numbers (C) A system that uses two distinct states or digits (D) A system that uses three distinct states or digits 42. What is the main purpose of a crystal oscillator in electronic circuits? (A) To filter high-frequency noise (B) To amplify weak signals (C) To provide a stable clock signal (D) To convert AC to DC 43. Which electronic component is typically used in power supply circuits to filter ripple voltage? (A) Inductor (B) Resistor (C) Capacitor (D) Diode 44. What is the primary purpose of a comparator in electronic systems? (A) To amplify weak signals (B) To compare two input voltages and output a signal based on their difference (C) To convert digital signals to analog (D) To store and release electrical energy 45. Which type of electronic component is used for amplifying very small signals in precision applications? (A) Diode (B) Transformer (C) Operational Amplifier (Op-Amp) (D) Capacitor 46. What is the role of a voltage divider circuit? (A) To split a voltage into smaller voltages (B) To amplify voltage (C) To convert AC voltage to DC voltage (D) To filter out unwanted frequencies 47. Which component is used to protect circuits from reverse voltage? (A) Zener diode (B) Schottky diode (C) Light-emitting diode (LED) (D) Rectifier diode 48. In a digital logic circuit, what does an XOR gate output when both inputs are different? (A) High (B) False (C) True (D) Low 49. Which type of signal is commonly used to control the brightness of an LED? (A) Low-frequency signal (B) Digital signal (C) High-frequency signal (D) Analog signal 50. What is the primary function of a multiplexer in electronic systems? (A) To amplify a single signal (B) To combine multiple signals into one output (C) To filter high-frequency noise (D) To regulate voltage