Signals and Switches Questions and Answers

Take Exam

Signals and Switches form the foundation of Digital Electronics, enabling the understanding of binary logic and circuit design. This section on Signals and Switches questions with answers is crucial for aspirants of GATE, DRDO, and ISRO technical exams. Here, you’ll explore digital signal behavior, voltage levels, transistor switching, and logic circuit implementations. Solving these electronics aptitude questions with explanations builds your understanding of how switching devices control logic states in digital systems. Regular practice ensures better performance in technical exams and interviews focusing on circuit-level analysis and Boolean logic.

Signals and Switches

Showing 10 of 27 questions

11. The serial format for transmitting binary information uses:

  • a single conductor
  • multiple conductors
  • infrared technology
  • fiber-optic
Show Answer Report

12. Which device(s) have almost ideal ON and OFF resistances?

  • electromechanical relays
  • manual switches
  • semiconductor devices (diodes and transistors)
  • electromechanical relays and manual switches
Show Answer Report

13. A diode placed in parallel across a relay coil serves what function?

  • to regulate input voltage
  • to protect the coil from arcing
  • to ensure most of the current passes through the coil
  • to reduce arcing across the relay contacts
Show Answer Report

14. Serial communication can be sped up by:

  • using silver or gold conductors instead of copper
  • using high-speed clock signals
  • adjusting the duty cycle of the binary information
  • using silver or gold conductors instead of copper and high-speed clock signals
Show Answer Report

15. TTL logic chips must have connections to Vcc and ground, even if all inputs and outputs are properly used and tied to valid signals.

  • TRUE
  • FALSE
Show Answer Report

16. An indication of cutoff in an NPN bipolar transistor is that the:

  • collector current is maximum
  • collector-to-emitter voltage equals zero
  • base-to-emitter voltage equals 0.7 V
  • collector to emitter appears to be open
Show Answer Report

17. Normal operation of an NPN bipolar transistor requires the base to be ________ with respect to the emitter, and ________ with respect to the collector.

  • positive, negative
  • positive, positive
  • negative, positive
  • negative, negative
Show Answer Report

18. The abbreviation NO, when used with respect to electromechanical relays, stands for not operational.

  • TRUE
  • FALSE
Show Answer Report

19. In a graphical representation of voltage versus time, ________ is displayed on the ________ axis and ________ is displayed on the ________ axis.

  • time, y, voltage, x
  • voltage, y, time, x
Show Answer Report

20. What is the minimum voltage required before a diode will allow current to flow between the cathode and the anode?

  • 0.7 V
  • 0.07 V
  • 4.3 V
  • 0.2 V
Show Answer Report
Questions and Answers for Competitive Exams Various Entrance Test