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Syllabus

NEC Computer · Practice

Chapters & sets

1. Basic Electrical and Electronics

Basic Electrical

Set 1106

Basic Electronics

Set 171 Set 233

2. Digital Logic and Microprocessor

Digital Logic

Set 150 Set 250 Set 350 Set 450 Set 550 Set 650 Set 749 Set 851 Set 950 Set 1050 Set 1150 Set 1232

Microprocessor

Set 150 Set 250 Set 350 Set 445 Set 550 Set 650 Set 720 Set 850 Set 969

3. Programming Language and Its Applications

Mixed chapter MCQs

Set 150 Set 249 Set 349 Set 451 Set 540

4. Computer Organization and Embedded System

Mixed chapter MCQs

Set 150 Set 249 Set 350 Set 450 Set 550 Set 650 Set 750 Set 849 Set 950 Set 1050 Set 1150

5. Concept of Computer Network and Network Security System

Basic Networking

Set 150 Set 253

Advanced Networking

Set 150 Set 250 Set 350 Set 450 Set 550 Set 655

6. Theory of Computation and Computer Graphics

Theory of Computation

Set 150 Set 250 Set 360

Computer Graphics

Set 150 Set 251 Set 350 Set 450 Set 550

7. Data Structures and Algorithm, Database System and Operating System

8. Software Engineering and Object-Oriented Analysis & Design

Mixed chapter MCQs

Set 150 Set 250 Set 350 Set 450 Set 550 Set 650 Set 750 Set 926

9. Artificial Intelligence and Neural Networks

Mixed chapter MCQs

Set 150 Set 317 Set 450 Set 550 Set 650 Set 750 Set 850 Set 932

10. Project Planning, Design and Implementation

Engineering Drawing

Set 150 Set 267

Engineering Economics

Set 168

Project Planning & Scheduling

Set 188

Project Mangement

Set 150

Engineering Professional Practice

Set 120

Engineering Regulatory Body

Set 130

Digital Logic Set 4

50 questions

Question 1

Which of the following logic families use bipolar transistors?

A.
$\text{TTL}$
B.
$\text{NMOS}$
C.

50

\text{GaAs}

D.

\text{CMOS}

Question 2

Which of the following TTL subfamilies is the fastest?

A.
$\text{Standard TTL}$
B.
$\text{Schottky TTL}$
C.
$\text{High-speed TTL}$
D.
$\text{Low-speed TTL}$

Question 3

The output 0 and 1 levels for TTL logic family are approximately:

A.
$0.1 \text{ and } 5V$
B.
$0.9 \text{ and } 1.75V$
C.
$0.6 \text{ and } 3.5V$
D.
$-1.75 \text{ and } -0.9V$

Question 4

The functional capacity of SSI devices is:

A.
$1 \text{ to } 11 \text{ gates}$
B.
$100 \text{ to } 10,000 \text{ gates}$
C.
$12 \text{ to } 99 \text{ gates}$
D.
$\text{More than } 10,000 \text{ gates}$

Question 5

The functional capacity for LSI devices is:

A.
$1 \text{ to } 11 \text{ gates}$
B.
$100 \text{ to } 10,000 \text{ gates}$
C.
$12 \text{ to } 99 \text{ gates}$
D.
$\text{More than } 10,000 \text{ gates}$

Question 6

The time required for a pulse to decrease from 90% to 10% of its maximum value is known as:

A.
$\text{Rise time}$
B.
$\text{Binary level transition period}$
C.
$\text{Decay time}$
D.
$\text{Propagation delay}$

Question 7

Which logic family dissipates the minimum power?

A.
$\text{DTL}$
B.
$\text{ECL}$
C.
$\text{TTL}$
D.
$\text{CMOS}$

Question 8

Which TTL subfamily has the maximum speed?

A.
$\text{Standard TTL}$
B.
$\text{High-speed TTL}$
C.
$\text{Schottky-clamped TTL}$
D.
$\text{Low-power TTL}$

Question 9

Which of the following is the first integrated logic family?

A.
$\text{RTL}$
B.
$\text{TTL}$
C.
$\text{DTL}$
D.
$\text{MOS}$

Question 10

Why are digital circuits easier to design than analog circuits?

A.
$\text{They do not control electricity precisely over a wide range}$
B.
$\text{They are made in the form of ICs}$
C.
$\text{All elements of digital circuits are from the same family}$
D.
$\text{They are smaller in size}$

Question 11

Which of the following electronic components is not found in ordinary ICs?

A.
$\text{Diodes}$
B.
$\text{Transistors}$
C.
$\text{Resistors}$
D.
$\text{Inductors}$

Question 12

The fan-out capability of a digital building block can be defined as:

A.
$\text{The number of inputs that one output can transmit to}$
B.
$\text{The amount of cooling required for fanning the heat out}$
C.
$\text{The number of inputs that can transmit to one input}$
D.
$\text{The maximum power dissipation (heat generation) that the unit can stand}$

Question 13

What is the main advantage of using MOSFET rather than bipolar transistor circuitry in ICs?

A.
$\text{Much greater complexity (more components) than bipolar circuits; better economy}$
B.
$\text{Higher operating speed than bipolar circuits}$
C.
$\text{Fewer power supply connections are required with MOS ICs}$
D.
$\text{System designers are more familiar with MOS circuitry}$

Question 14

FETs are used in linear ICs to:

A.
$\text{Increase input resistance}$
B.
$\text{Increase device complexity}$
C.
$\text{Provide large resistance}$
D.
$\text{A and B above}$

Question 15

Resistor Ratio design is used in linear ICs because:

A.
$\text{Ratio increases input resistance}$
B.
$\text{Ratio increases amplifier gain}$
C.
$\text{Precise resistor values are not possible with IC processes}$
D.
$\text{All of the above}$

Question 16

A p-channel enhancement-type MOSFET performs much the same functions as a PNP transistor, except that:

A.
$\text{It operates much faster}$
B.
$\text{It is considerably larger}$
C.
$\text{It is controlled by voltage rather than by current, so it requires very little current at the control terminal}$
D.
$\text{It is controlled by current than voltage like a bipolar transistor}$

Question 17

What advantages do ICs have over discrete-device circuits due to their greater complexity (i.e., more circuitry in less area)?

A.
$\text{Smaller size}$
B.
$\text{Lower cost}$
C.
$\text{Higher reliability}$
D.
$\text{All of the above}$

Question 18

The radix of the binary number is:

A.
$3$
B.
$2$
C.
$1$
D.
$10$

Question 19

The number of binary bits required to represent a hexadecimal digit is:

A.
$3$
B.
$6$
C.
$4$
D.
$8$

Question 20

The logical expression

A + B + C = D

represents:

A.
$\text{NAND gate}$
B.
$\text{EX-OR gate}$
C.
$\text{OR gate}$
D.
$\text{AND gate}$

Question 21

The output of the following gate is 1 only if at least one of its inputs is 0:

A.
$\text{AND gate}$
B.
$\text{NAND gate}$
C.
$\text{OR gate}$
D.
$\text{NOT gate}$

Question 22

The 1's complement of binary number 0.01011 is:

A.
$1.10100$
B.
$0.0110$
C.
$0.0010$
D.
$-1.1101$

Question 23

The 2's complement of binary number 0.01010 is:

A.
$1.10101$
B.
$1.10100$
C.
$0.10101$
D.
$0.10100$

Question 24

A half-adder is also known as:

A.
$\text{AND circuit}$
B.
$\text{NOR circuit}$
C.
$\text{NAND circuit}$
D.
$\text{EX-OR circuit}$

Question 25

The output of the following gate is 0 only if at least one of the inputs is 1:

A.
$\text{AND gate}$
B.
$\text{EX-OR gate}$
C.
$\text{OR gate}$
D.
$\text{NOR gate}$

Question 26

Which of the following Boolean algebra rules is wrong?

A.
$0 + A = A$
B.
$A + A = A$
C.
$1 + A = 1$
D.
$1 \cdot A = 1$

Question 27

The octal system has the radix of:

A.
$2$
B.
$8$
C.
$4$
D.
$10$

Question 28

The binary system has the radix of:

A.
$0$
B.
$2$
C.
$1$
D.
$10$

Question 29

Octal number system uses fundamental digits 0 to 7. 124 (octal) in decimal equivalent is equal to:

A.
$180$
B.
$84$
C.
$82$
D.
$86$

Question 30

92 (decimal) in the octal number system is equivalent to:

A.
$128_8$
B.
$132_8$
C.
$130_8$
D.
$134_8$

Question 31

Four-digit binary quantity 1001 is represented in the decimal system by:

A.
$7$
B.
$1$
C.
$9$
D.
$13$

Question 32

Binary number 101101 is equivalent in decimal form to:

A.
$41$
B.
$45$
C.
$43$
D.
$47$

Question 33

Number 373₁₀ is equivalent in the binary system to:

A.
$101110101$
B.
$101010101$
C.
$100110101$
D.
$101110011$

Question 34

According to Boolean algebra,

A + A =

A.
$A$
B.
$A/n$
C.
$NA$
D.
$1$

Question 35

In Boolean algebra,

A \cdot A \cdot A \cdot A \cdot A =

A.
$A$
B.
$A^5$
C.
$A/5$
D.
$A$

Question 36

In Boolean algebra,

A \cdot 0 =

A.
$1$
B.
$A$
C.
$0$
D.
$1 + A$

Question 37

The simplification of

AB + BC + BC

gives:

A.
$AB + BC$
B.
$BC + BC$
C.
$AB + BC$
D.
$B$

Question 38

Which of the following is not functionally a complete set?

A.
$\text{AND, OR}$
B.
$\text{NOR}$
C.
$\text{NAND}$
D.
$\text{AND, OR, NOT}$

Question 39

Which of the following is not true?

A.
$0 \times 0 = 0$
B.
$1 \times 0 = 0$
C.
$0 \times 1 = 1$
D.
$1 \times 1 = 1$

Question 40

The reduced form of the Boolean expression

(A + B)(A + C)

is:

A.
$AB + AC$
B.
$AC + B$
C.
$A + B + C$
D.
$A + BC$

Question 41

Which of the following is a universal gate?

A.
$\text{AND}$
B.
$\text{EX-OR}$
C.
$\text{OR}$
D.
$\text{NAND}$

Question 42

Which function in positive logic is equivalent to the OR function in negative logic?

A.
$\text{NOT}$
B.
$\text{OR}$
C.
$\text{AND}$
D.
$\text{NOR}$

Question 43

Which of the following logic expressions is wrong?

A.
$1 + 0 = 1$
B.
$1 + 0 + 1 = 1$
C.
$1 + 1 = 0$
D.
$1 + 1 + 1 = 1$

Question 44

The m-bit parallel adder consists of:

A.
$(m + 1) \text{ full adders}$
B.
$m - 1 \text{ full adders}$
C.
$m^2 \text{ full adders}$
D.
$m \text{ full adders}$

Question 45

A flip-flop can store:

A.
$1 \text{ bit of data}$
B.
$3 \text{ bits of data}$
C.
$2 \text{ bits of data}$
D.
$4 \text{ bits of data}$

Question 46

A shift register can be used for:

A.
$\text{Parallel to serial conversion}$
B.
$\text{Digital delay line}$
C.
$\text{Serial to parallel conversion}$
D.
$\text{All of the above}$

Question 47

Semiconductor memory is:

A.
$\text{Somewhat larger than magnetic core memory}$
B.
$\text{A volatile memory}$
C.
$\text{Somewhat larger than magnetic core memory}$
D.
$\text{All of the above}$

Question 48

The logic 1 in a positive logic system is represented by:

A.
$\text{Zero voltage}$
B.
$\text{Higher voltage level}$
C.
$\text{Lower voltage level}$
D.
$\text{Negative voltage}$

Question 49

A combinational logic circuit used to send data coming from a single source to two or more separate destinations is called:

A.
$\text{Decoder}$
B.
$\text{Multiplexer}$
C.
$\text{Encoder}$
D.
$\text{Demultiplexer}$

Question 50

A logic circuit used to change a BCD number into an equivalent decimal number is:

A.
$\text{Decoder}$
B.
$\text{Multiplexer}$
C.
$\text{Encoder}$
D.
$\text{Code converter}$

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