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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 5

50 questions

Question 1

A combinational logic circuit which generates a particular binary word or number is:

A.
$\text{Decoder}$
B.
$\text{Encoder}$
C.

50

\text{Multiplexer}

D.

\text{De-multiplexer}

Question 2

Parallel adders are:

A.
$\text{Combinational logic circuits}$
B.
$\text{Sequential logic circuits}$
C.
$\text{Both of the above}$
D.
$\text{None of the above}$

Question 3

A de-multiplexer is also known as:

A.
$\text{Data selector}$
B.
$\text{Multiplexer}$
C.
$\text{Data distributor}$
D.
$\text{Encoder}$

Question 4

A multiplexer is known as:

A.
$\text{Coder}$
B.
$\text{Data selector}$
C.
$\text{Decoder}$
D.
$\text{Encoder}$

Question 5

A flip-flop can store:

A.
$\text{One bit of data}$
B.
$\text{Three bits of data}$
C.
$\text{Two bits of data}$
D.
$\text{Any number of bits of data}$

Question 6

Which of the following input combinations is not allowed in an SR flip-flop?

A.
$S=0, R=0$
B.
$S=1, R=0$
C.
$S=0, R=1$
D.
$S=1, R=1$

Question 7

When an inverter is placed between both inputs of an SR flip-flop, the resulting flip-flop is:

A.
$\text{JK flip-flop}$
B.
$\text{T flip-flop}$
C.
$\text{D flip-flop}$
D.
$\text{Master-slave JK flip-flop}$

Question 8

The clock signals are used in sequential logic circuits to:

A.
$\text{Tell the time of the day}$
B.
$\text{Tell how much time has elapsed since the system was turned on}$
C.
$\text{Carry serial data signals}$
D.
$\text{Synchronize events in various parts of a system}$

Question 9

What logic function is obtained by adding an inverter to the output of an AND gate?

A.
$\text{OR}$
B.
$\text{XOR}$
C.
$\text{NAND}$
D.
$\text{NOR}$

Question 10

The simplified form of the Boolean expression ( (X + Y + XY)(X + Z) ) is:

A.
$X + Y + Z$
B.
$X + YZ$
C.
$XY + YZ$
D.
$XZ + Y$

Question 11

The highest decimal number that can be represented with 10 binary digits is:

A.
$1023$
B.
$512$
C.
$1024$
D.
$2048$

Question 12

What is the hexadecimal equivalent of the binary number 10101111?

A.
$AF$
B.
$8C$
C.
$OF$
D.
$All of the above$

Question 13

Which of the following logic families has the highest noise immunity?

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

Question 14

Pick up the wrong logical expression:

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

Question 15

In a four-input NAND gate, all but one input is 1. The output is:

A.
$4$
B.
$1$
C.
$0$
D.
$\text{Undefined}$

Question 16

In a four-input AND gate, all but one input is 1. The output is:

A.
$0$
B.
$1$
C.
$\text{Undefined}$
D.
$4$

Question 17

According to the Idempotent law, ( X + X = ):

A.
$1$
B.
$X$
C.
$0$
D.
$X \cdot X$

Question 18

According to the Idempotent law, ( X \cdot X = ):

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

Question 19

The output will be one in case any input is one in the case of:

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

Question 20

Which of the following circuits is known as a half adder?

A.
$\text{EXCLUSIVE AND circuit}$
B.
$\text{INCLUSIVE OR circuit}$
C.
$\text{Flip-flop circuit}$
D.
$\text{EXCLUSIVE OR circuit}$

Question 21

Which of the following functions is referred to as the complementary function?

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

Question 22

Which of the following statements illustrates the distributive law?

A.
$(A + B) + C = A + (B + C) = A + B + C$
B.
$(A \cdot B) \cdot C = A \cdot (B \cdot C) = A \cdot B \cdot C$
C.
$A + B = B + A$
D.
$A \cdot (B + C) = (A \cdot B) + (A \cdot C)$

Question 23

Which of the following is termed as the minimum error code?

A.
$\text{Binary code}$
B.
$\text{Excess-3 code}$
C.
$\text{Gray code}$
D.
$\text{Octal code}$

Question 24

For which of the following flip-flops is the output clearly defined for all combinations of two inputs?

A.
$\text{D-type flip-flop}$
B.
$\text{JK flip-flop}$
C.
$\text{R-S flip-flop}$
D.
$\text{T flip-flop}$

Question 25

A 4-bit shift register can be made by using:

A.
$3 \text{ JK flip-flops}$
B.
$5 \text{ JK flip-flops}$
C.
$4 \text{ JK flip-flops}$
D.
$8 \text{ JK flip-flops}$

Question 26

Which of the following statements is false?

A.
$\overline{A \cdot B} = \overline{A} + \overline{B}$
B.
$\overline{A + B} = \overline{A} \cdot \overline{B}$
C.
$A + B = \overline{A} \cdot \overline{B}$
D.
$A + A = A$

Question 27

The minimum form of the expression ( (A + B)(A + B + C) ) is:

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

Question 28

One's complement of 1011.01 is:

A.
$0100.10$
B.
$1011.10$
C.
$0100.11$
D.
$0100.01$

Question 29

The NAND gate output will be low if the two inputs are:

A.
$00$
B.
$10$
C.
$01$
D.
$11$

Question 30

What is the binary equivalent of the decimal number 368?

A.
$101110000$
B.
$111010000$
C.
$110110000$
D.
$111100000$

Question 31

The decimal equivalent of the hexadecimal number 1A53 is:

A.
$6793$
B.
$6973$
C.
$6739$
D.
$6379$

Question 32

The octal equivalent of the decimal number 324.987 is:

A.
$504.771$
B.
$815.234$
C.
$640.781$
D.
$90.987$

Question 33

The simplification of the Boolean expression ( (A \cdot B \cdot C) + (A \cdot B \cdot \overline{C}) ) is:

A.
$0$
B.
$A$
C.
$A \cdot B$
D.
$B \cdot C$

Question 34

The number of control lines for an 8-to-1 multiplexer is:

A.
$2$
B.
$4$
C.
$3$
D.
$5$

Question 35

How many flip-flops are required for a mod-16 counter?

A.
$5$
B.
$3$
C.
$4$
D.
$6$

Question 36

EPROM contents can be erased by exposing it to:

A.
$\text{Ultraviolet light}$
B.
$\text{Burst of microwaves}$
C.
$\text{Infrared rays}$
D.
$\text{Intense heat radiations}$

Question 37

The hexadecimal number 'A0' has the decimal value equivalent to:

A.
$80$
B.
$100$
C.
$256$
D.
$160$

Question 38

The Gray code for decimal number 6 is equivalent to:

A.
$1100$
B.
$0101$
C.
$1001$
D.
$0110$

Question 39

The Boolean expression ( A \cdot B + A \cdot \overline{B} + \overline{A} \cdot B ) is equivalent to:

A.
$A + B$
B.
$A \cdot B$
C.
$\overline{A} + \overline{B}$
D.
$A \oplus B$

Question 40

The 2's complement of the binary number 1101101 is:

A.
$0010011$
B.
$0010010$
C.
$0010001$
D.
$0010000$

Question 41

The digital logic family which has minimum power dissipation is:

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

Question 42

The output of a logic gate is 1 when all its inputs are at logic 0. The gate is either:

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

Question 43

Data can be changed from special code to temporal code by using:

A.
$\text{Shift registers}$
B.
$\text{Combinational circuits}$
C.
$\text{Counters}$
D.
$\text{Multiplexers}$

Question 44

A ring counter consisting of five flip-flops will have:

A.
$5 \text{ states}$
B.
$32 \text{ states}$
C.
$10 \text{ states}$
D.
$\text{Infinite states}$

Question 45

The speed of conversion is maximum in:

A.
$\text{Successive-approximation A/D converter}$
B.
$\text{Parallel-comparator A/D converter}$
C.
$\text{Counter-ramp A/D converter}$
D.
$\text{Dual-slope A/D converter}$

Question 46

The 2's complement of the number 1101101 is:

A.
$0010011$
B.
$0010010$
C.
$0010001$
D.
$0010000$

Question 47

The correction to be applied in a decimal adder to the generated sum is:

A.
$A + B$
B.
$A \cdot B$
C.
$\overline{A} + \overline{B}$
D.
$\overline{A} \cdot \overline{B}$

Question 48

When simplified with Boolean algebra, ( (x + y)(x + z) ) simplifies to:

A.
$x$
B.
$x + yz$
C.
$x + y + z$
D.
$x(y + z)$

Question 49

The gates required to build a half adder are:

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

Question 50

The code where all successive numbers differ from their preceding number by a single bit is:

A.
$\text{Binary code}$
B.
$\text{Excess-3 code}$
C.
$\text{BCD code}$
D.
$\text{Gray code}$

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