Signals and Switches MCQs

Question 1

The serial format for transmitting binary information uses:

Accepted Answer

a single conductor

Answer

multiple conductors

Answer

infrared technology

Answer

fiber-optic

Question 2

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

Accepted Answer

electromechanical relays and manual switches

Answer

electromechanical relays

Answer

manual switches

Answer

semiconductor devices (diodes and transistors)

Question 3

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

Accepted Answer

to protect the coil from arcing

Answer

to regulate input voltage

Answer

to ensure most of the current passes through the coil

Answer

to reduce arcing across the relay contacts

Question 4

Serial communication can be sped up by:

Accepted Answer

using high-speed clock signals

Answer

using silver or gold conductors instead of copper

Answer

adjusting the duty cycle of the binary information

Answer

using silver or gold conductors instead of copper and high-speed clock signals

Question 5

What is the period of a clock waveform that has a frequency of 15.4 kHz?

Accepted Answer

64.9 s

Answer

649 s

Answer

6.49 s

Answer

0.649 s

Question 6

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

Accepted Answer

collector to emitter appears to be open

Answer

collector current is maximum

Answer

collector-to-emitter voltage equals zero

Answer

base-to-emitter voltage equals 0.7 V

Question 7

When an IC has two rows of parallel connecting pins, the device is referred to as a:

Accepted Answer

DIP

Answer

QFP

Answer

TSSOP

Answer

CMOS

Question 8

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

Accepted Answer

positive, negative

Answer

positive, positive

Answer

negative, positive

Answer

negative, negative

Question 9

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

Accepted Answer

0.7 V

Answer

0.07 V

Answer

4.3 V

Answer

0.2 V