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Syllabus

NEC Electronics · Practice

Chapters & sets

1. Basic Electrical and Electronics Engineering

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 Systems

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. Computer Networks and Network Security

Basic Networking

Set 150 Set 253

Advanced Networking

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

10. Project Planning, Design and Implementation

Digital Logic Set 2

50 questions

Question 1

The binary code of (73)10 is

A.
1010001
B.
1100101
C.
1000100
D.
1001001

Question 2

An AND gate will function as OR if

A.

All the inputs to the gates are "1"

B.

All the inputs are "0"

C.

Either of the inputs is "1"

D.

All the inputs and outputs are complemented

Question 3

An OR gate has 6 inputs. How many input words are in its truth table?

A.
64
B.
16
C.
32
D.
128

Question 4

An OR gate has 6 inputs. What is the only input word that produces a 0 input?

A.
000000
B.
111000
C.
000111
D.
111111

Question 5

An AND gate has 7 inputs. How many input word are in its truth?

A.
64
B.
16
C.
32
D.
128

Question 6

An AND gate has 7 inputs, what is the only input word that produces a 1 output?

A.
0000000
B.
1110000
C.
0001111
D.
1111111

Question 7

A NOR gate has or more input signals. All inputs must be … to get a high output

A.
Low
B.
Some low some high
C.
High
D.
1's

Question 8

A NOR gate recognizes only the input word whose bits are…

A.
0's and 1's
B.
0's
C.
1's
D.
0's or 1's

Question 9

The NOR gate is logically equivalent to an OR gate followed by an …

A.
AND
B.
XOR
C.
XAND
D.
Inverter

Question 10

De Morgan's first theorem says that a NOR gate is equivalent to a bubbled … gate

A.
AND
B.
XOR
C.
XAND
D.
NOR

Question 11

A NAND gate is equivalent to an AND gate followed by an inverter. All inputs must be…to get a low output

A.
Low
B.
Some low and some high
C.
High
D.
0's

Question 12

De Morgan's second theorem says that NAND gate is equivalent to a bubbled ……gate

A.
AND
B.
XOR
C.
XAND
D.
OR

Question 13

An XOR gate recognizes only words with an ……number of 1's

A.
Even
B.
Different
C.
Odd
D.
All of the above

Question 14

The 2-input XOR gate has a high output only when the input bits are…

A.
Even
B.
Low
C.
Different
D.
High

Question 15

The XOR gates are ideal for testing parity because even-parity words produce a …. Output and odd-parity words produce a ……output

A.
Low, high
B.
Odd, even
C.
High, low
D.
Even, odd

Question 16

An odd-parity generator produces an odd-parity bit to go along with the data. The parity of the transmitted data is ….. An XOR gate can test each received word for parity rejecting words with …. Parity

A.
Odd, even
B.
Low, high
C.
High, low
D.
Even, odd

Question 17

The EXCLUSIVE-NOR gate is equivalent to an ……gate followed by an inverter

A.
OR
B.
NAND
C.
AND
D.
XOR

Question 18

Small-scale integration, abbreviated ….. refers to fewer than 12 gates on the same chip. Medium-scale integration (MSD) means 12 to 100 gates per chip. And large-scale integration (LST) refers to more than ……gates per chip

A.
SSI, 75
B.
SSI, 1000
C.
SSI, 100
D.
SSI, 10000

Question 19

The two basic technologies for digital ICs are bipolar and MOS. Bipolar technology is preferred for ...... and ...... whereas MOS technology is better suited to LSI

A.
SSI, MSI
B.
SSI, LSI
C.
MSI, LSI
D.
ECL, DTL

Question 20

What is 1's complement of 0000 1111 0010 1101 number?

A.
1111 0000 0010 1101
B.
1111 0000 1101 0010
C.
1111 0000 0010 1101
D.
1111 1100 1010 1100

Question 21

.....has become the most widely used bipolar family

A.
DTL
B.
ECL
C.
TTL
D.
MOS

Question 22

.....is the fastest logic family' it's used in high-speed applications

A.
DTL
B.
ECL
C.
TTL
D.
MOS

Question 23

.....dominates the LSI field and ....used extensively where lowest power consumption is necessary

A.
NMOS, PMOS
B.
NMOS, CMOS
C.
PMOS, CMOS
D.
MOSFET, PMOS

Question 24

The 7400 series, also called standard TTL, contains a variety of SSI and ... chips that allow us to build all kinds of digital circuits and systems

A.
LSI
B.
MOS
C.
MSI
D.
MOSFET

Question 25

Standard TTL has a multiple emitter input transistor and a ..... output

A.
Totem-pole
B.
Register
C.
Bipolar
D.
Transistor

Question 26

The 7400-series devices are guaranteed to work reliably over a temperature range of 0 to .... and over a voltage range of 4.75 to 5.25 V

A.
80(^\circ)C
B.
100(^\circ)C
C.
70(^\circ)C
D.
90(^\circ)C

Question 27

A ... TTL device can sink up to 16 mA and can source up to 400MA

A.
Low-power
B.
Standard
C.
High-power
D.
Schottky

Question 28

The maximum number of TTL loads that a TTL device can drive reliably over the specified temperature range is

A.
Fanout
B.
Chip
C.
Bipolar
D.
Universal logic circuit

Question 29

Digital design often starts by constructing a ..... table?

A.
Standard
B.
Truth
C.
Two-Stage
D.
Two-dimensional

Question 30

A preliminary guide for comparing the simplicity of logic circuits to count the number of input......leads

A.
Wires
B.
Transistors
C.
Gates
D.
Registers

Question 31

A bus is a group of .....carrying digitals signals

A.
Wires
B.
Transistors
C.
Gates
D.
Registers

Question 32

One way to simplicity the sum-of-products equation is to use Boolean algebra. Another way is the .....map

A.
De Morgan
B.
Schottky
C.
Standard
D.
Karnaugh

Question 33

What are the fundamental products for inputs words ABCD = 0010, ABCD = 1101 and ABCD = 1110?

A.
ABCD, ABCD, ABCD
B.
ABCD, ABCD, ABCD
C.
ABCD, ABCD, ABCD
D.
ABCD, ABCD, ABCD

Question 34

The ALU carries out arithmetic and numbers rather than decimal numbers

A.
Decimal
B.
Binary
C.
Hexadecimal
D.
All of the above

Question 35

A half-adder adds....bits

A.
16
B.
19
C.
8
D.
2

Question 36

A full-adder adds ....bits and producing a SUM and a....

A.
8, SUBTRACTION
B.
16,DIVIDE
C.
3, CARRY
D.
All of the above

Question 37

A binary adder is a logic circuit that can add.....binary numbers at a time

A.
Hundreds
B.
One
C.
Thousands
D.
Two

Question 38

The leading bit stands for the ...and the remaining bits for the ..., is known as signed binary numbers

A.
Sign, remainder
B.
Value, sign
C.
Sign, magnitude
D.
Variable, value

Question 39

Signed binary numbers requires too much hardware. This has led to the use of ... complements to represent negative numbers

A.
1's
B.
3's
C.
2's
D.
No

Question 40

A 2's-complement adder-subtracter can add or subtract binary numbers. Sign-magnitude numbers represent.....decimal numbers and 2's complements stands for .... Decimal numbers

A.
Hexa, sign
B.
Positive, negative
C.
Sign, hexa
D.
Negative, positive

Question 41

How many full and half-adders are required to add 16-bit numbers?

A.
8 half-adders, 8 full-adders
B.
16 half-adders, no full-adders
C.
Half-adders, 15 full-adders
D.
Half-adders, 12 full-address

Question 42

Express-7 as 16-bits signed binary numbers

A.
0000 0000 0000 0111
B.
0111 0000 0000 0000
C.
1000 0000 0000 0111
D.
0111 0000 0000 0000

Question 43

Convert the 1000 0000 0000 1111 signed binary number to decimal number

A.
+15
B.
-30
C.
-15
D.
+30

Question 44

What is the 2's complement of 0011 0101 1001 1100 number?

A.
-1100 1001 1100 1011
B.
1100 1010 0110 0100
C.
1100 1010 0110 0011
D.
1100 1010 1111 1111

Question 45

What is the 2's-complement presentation of -24 in a 16-bit microcomputer?

A.
0000 0000 0001 1000
B.
1111 1111 1110 1000
C.
1111 1111 1110 0111
D.
0001 0001 1111 0011

Question 46

A flip-flop is a ...element that stores a binary digit as a low or high voltage

A.
Chip
B.
I/O
C.
Bus
D.
Memory

Question 47

With an RS latch a high S and low R sets the output to ...,; a low S and a high R....the output to low

A.
No change, set
B.
High, reset
C.
Race, high
D.
Set. Reset

Question 48

With a NAND latch a low R and a low S produce a:.....condition

A.
Race
B.
Reset
C.
Set
D.
No change

Question 49

Computers use thousands of flip-flops. To coordinate the overall action, a common signal called the ...is sent to each flip-flop

A.
Latch
B.
Master
C.
Clock
D.
Slave

Question 50

With positive clocking the clock signal must be.....for the flip-flop to respond

A.
High
B.
Set
C.
Low
D.
Race

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