Explore topic-wise MCQs in Digital Electronics.

This section includes 139 Mcqs, each offering curated multiple-choice questions to sharpen your Digital Electronics knowledge and support exam preparation. Choose a topic below to get started.

1.

The range of voltages between V and V are ________.

A. unknown
B. unnecessary
C. unacceptable
D. between 2 V and 5 V
Answer» D. between 2 V and 5 V
2.

A periodic digital waveform has a pulse width (t) of 6 ms and a period (T) of 18 ms. The duty cycle is ________.

A. 3.3%
B. 33.3%
C. 6%
D. 18%
Answer» C. 6%
3.

What is the decimal value of 2?

A. 2
B. 4
C. 6
D. 8
Answer» E.
4.

In a typical digital system, Logic 0 is 0V–0.8V, and Logic 1 is ________.

A. 2–5V
B. 2.5–5V
C. 3.0–5.5V
D. 3.5–5.5V
Answer» B. 2.5–5V
5.

What is the decimal value of 2–1 ?

A. 0.5
B. 0.25
C. 0.05
D. 0.1
Answer» B. 0.25
6.

A(n)________ is not a functional unit of a computer.

A. input unit
B. memory unit
C. modem
D. control unit
Answer» D. control unit
7.

In ________ transmission, a single conductor is used.

A. digital
B. automatic
C. serial
D. binary
Answer» D. binary
8.

In a binary system there are only two symbols.

A. 1
B.
Answer» B.
9.

A logic circuit that can store one bit of information is a ________.

A. flip-flop
B. counter
C. gate
D. code converter
Answer» B. counter
10.

A microcomputer is the smallest type of computer.

A. 1
B.
Answer» B.
11.

PALs are relatively simple integrated circuit devices.

A. 1
B.
Answer» B.
12.

Greater accuracy and precision are possible with digital techniques.

A. 1
B.
Answer» B.
13.

The duty cycle of a square wave is ________.

A. 0.1
B. 0.25
C. 0.5
D. 1
Answer» D. 1
14.

An inverter performs a NOT operation.

A. 1
B.
Answer» B.
15.

The area represented by #4 in the given figure is the ________ level.

A. HIGH
B. LOW
C. off
D. unacceptable
Answer» E.
16.

X-ray, MRI, and ultrasound systems in hospitals are examples of analog systems.

A. 1
B.
Answer» B.
17.

A graph of phase vs. time is a timing diagram.

A. 1
B.
Answer» C.
18.

The CPU contains all the circuitry for ________.

A. storing data
B. keeping track of time
C. fetching and interpreting instructions
D. Internet operations
Answer» D. Internet operations
19.

The digit that changes most often when counting is called the ________.

A. LSB
B. LL Bean
C. LED
D. LCD
Answer» B. LL Bean
20.

The control and arithmetic/logic units are often considered as one unit called the ________.

A. central processing unit
B. inputs and outputs
C. microcomputer
D. arithmetic/logic unit
Answer» B. inputs and outputs
21.

A binary number can be converted to be viewed on a 7-segment display by a(n) ________.

A. decoder
B. encoder
C. multiplexer
D. magnitude comparator
Answer» B. encoder
22.

It is possible to have an overlap between high and low levels in digital logic.

A. 1
B.
Answer» C.
23.

With an OR gate, the output is HIGH only when both inputs are HIGH.

A. 1
B.
Answer» C.
24.

The real world is mainly analog.

A. 1
B.
Answer» B.
25.

The controls on an oscilloscope that will help obtain a stable display are in the ________.

A. vertical section
B. horizontal section
C. trigger section
D. display section
Answer» D. display section
26.

Binary means having two states or values.

A. 1
B.
Answer» B.
27.

Circuits that exhibit the property of memory normally revert to their original state when the input is removed.

A. 1
B.
Answer» C.
28.

The rise-time of a pulse is normally measured between the ________.

A. 0 and 100% level
B. 10% and 90% level
C. 30% and 70% level
D. 50% level on the leading edge to the 50% level on the trailing edge
Answer» C. 30% and 70% level
29.

The decimal system is composed of ________ symbols.

A. 2
B. 8
C. 10
D. 16
Answer» D. 16
30.

The time interval on the leading edge of a pulse between 10% and 90% of the amplitude is the rise time.

A. 1
B.
Answer» B.
31.

Using digital techniques of information storage is easy.

A. 1
B.
Answer» B.
32.

Memory devices that use electronic latching circuits are called ________.

A. RAM
B. flip-flops
C. magnetic tape
D. DRAM
Answer» C. magnetic tape
33.

________ is the highest-value seven-bit binary number.

A. 128
B. 127
C. 126
D. 125
Answer» C. 126
34.

The LSB is always to the right of the MSB.

A. 1
B.
Answer» B.
35.

To determine which of two binary numbers is larger, you could use a(n) ________.

A. register
B. adder
C. encoder
D. magnitude comparator
Answer» E.
36.

Digital systems require that voltage levels change between high and low.

A. 1
B.
Answer» B.
37.

The value of the data shown in the given figure is ________.

A. between 0 and 1
B. 1011001
C. 5
D. 1001101
Answer» C. 5
38.

A microprocessor that performs only specific, dedicated tasks is also called a ________.

A. microcontroller
B. calculator
C. laptop microrocmputer
D. workstation processor
Answer» B. calculator
39.

One advantage of analog circuits over digital circuits is that it's easier to store data.

A. 1
B.
Answer» C.
40.

The horizontal axis of an oscilloscope is normally calibrated in units of ________.

A. voltage
B. current
C. time
D. frequency
Answer» D. frequency
41.

The CPU (Central Processing Unit) is composed of memory and outputs.

A. 1
B.
Answer» C.
42.

If a HIGH logic level is assigned a binary zero (0), and a low level is assigned a binary one (1), the logic is called ________.

A. negative logic
B. positive logic
C. invalid logic
D. assertion-level logic
Answer» B. positive logic
43.

Four bits equal one byte.

A. 1
B.
Answer» C.
44.

In a positive logic system, the HIGH level is usually represented by ________.

A. 0 V
B. +1 V
C. +5 V
D. +9 V
Answer» D. +9 V
45.

The arithmetic/logic unit will send the results of its decisions to memory.

A. 1
B.
Answer» C.
46.

Other ________ are often used to interpret or represent binary quantities for the convenience of the people who work with and use these digital systems.

A. analog systems
B. digital systems
C. number systems
D. binary systems
Answer» D. binary systems
47.

In a negative logic system, a high is represented by 0.

A. 1
B.
Answer» B.
48.

In ________ the quantities are not represented by continuously variable indicators.

A. analog representation
B. digital representation
C. signal representation
D. computer representation
Answer» C. signal representation
49.

A set of instructions for a computer is called a(n) ________.

A. instruction manual
B. logic unit
C. program
D. diagram
Answer» D. diagram
50.

Demultiplexing is a logic function that ________.

A. determines which of several inputs is the greatest
B. switches logic from one input to any of several output lines
C. switches logic from several inputs onto one output line
D. converts a code from one form to another
Answer» C. switches logic from several inputs onto one output line