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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

Theory of Computation Set 1

50 questions

Question 1

Let

R_1

and

R_2

50

be regular sets defined over alphabet

\sum

then

A.
$R_1 \cup R_2$ is regular
B.
$\sum \cap R_2$ is not regular
C.
$R_1 \cap R_2$ is not regular
D.
$R_2$ is not regular

Question 2

Consider the production of the grammar

S \rightarrow AA

\

A \rightarrow aa

\

A \rightarrow bb

Describe the language specified by the production grammar

A.
$L = {aaaa, aabb, bbaa, bbbb}$
B.
$L = {abab, abaa, aaab, baaa}$

Question 3

Give a production grammar that specifies the language

L = {a^i b^{2j} / i \geq 1}

A.
${S \rightarrow aSbb, S \rightarrow abb}$
B.
${S \rightarrow aA, S \rightarrow b, A \rightarrow b}$
C.
${S \rightarrow aSb, S \rightarrow b}$
D.
None of the above

Question 4

Which of the following string can be obtained by the language

L = {a^i b^{2j} / i \geq 1}

A.
Aaabbbbbb
B.
Abbabbba
C.
aabb
D.
aaaabbbbbb

Question 5

Give a production grammar for the language

L = \{x \mid x \in \{a,b\}^{*},\ \text{the number of }a\text{'s in }x\text{ is a multiple of }3\}

.

A.
${S \rightarrow bS, S \rightarrow b, S \rightarrow aA, S \rightarrow bA, A \rightarrow aB, B \rightarrow bB, B \rightarrow aS, S \rightarrow a}$

Question 6

Let

L1 = {a^b / i > j}

and

L2 = {a^b / i < j}

: the union of

L1

and

L2

is given by

A.
${a^b / i, j \geq 1}$
B.
a^b / i > j \geq 1}
C.
${a^b / i, j \geq 1}$

Question 7

Give a production grammar for the language

L = {a^b / I, j \geq 1, i \neq j}

A.
${S \rightarrow aS, S \rightarrow aB, B \rightarrow ab, A \rightarrow aaB, B \rightarrow b}$

Question 8

The production grammar is

{S \rightarrow aSbb, S \rightarrow abb}

is

A.
Type-3 grammar
B.
Type-1 grammar
C.
Type-3 grammar
D.
Type-0 grammar

Question 9

Which of the following statement is wrong?

A.
A Turing machine cannot solve halting problem
B.
Set of recursively enumerable languages is closed under union
C.
A finite State Machine with 2 stacks
D.
Context sensitive grammar can be recognized by a linearly bounded memory machine

Question 10

Which of the following statement is wrong?

A.
Recursive language are closed under union
B.
Recursive language are closed under union
C.
If a language and its complement are both regular, then the language must be recursive
D.
A language is accepted by FA if and only if it is recursive

Question 11

Which of the following statement is wrong?

A.
Every recursive language is recursively enumerable
B.
A language is accepted by FA if and only if it is context free
C.
Recursive languages are closed under intersection
D.
A language is accepted by a FA if and only if it is right linear

Question 12

Which of the following statement is true?

A.
All language can be generated by CFG
B.
The number of symbols unnecessary to simulate a Turing Machine (TM) with $m$ symbols and $n$ states is $mn$
C.
Any regular language has an equivalent CFG
D.
The class of CFG is not closed under union

Question 13

Recursively enumerable languages are not closed under

A.
Complementation
B.
Intersection
C.
Union
D.
None of the above

Question 14

Regular expression

(x/y)

denotes the set

A.
${xy, xy}$
B.
${x,y}$
C.
${xx,xy,yx,yy}$
D.
${x,y,xy}$

Question 15

Regular expression

x/y

denotes the set

A.
${x,y}$
B.
${xy}$
C.
${x}$
D.
${y}$

Question 16

The regular expressions denote a language comprising all possible strings of even length over the alphabet

{0,1}

A.
$1 + 0 (1 + 0)^*$
B.
$(1 + 0)$
C.
$(0 + 1) (1 + 0)^*$
D.
$(00 + 011 + 10)^*$

Question 17

The regular expressions denote zero or more instances of an

x

or

y

is

A.
$(x + y)$
B.
$(x^* + y)$
C.
$(x + y)^*$
D.
$(xy)^*$

Question 18

The regular expression has all strings in which any number of 0's is followed by any number of 1's followed by any number of 2's is:

A.
$(0 + 1 + 2)^*$
B.
$0^* + 1 + 2$
C.
$0^* 1^* 2^*$
D.
$(0 + 1)^* 2^*$

Question 19

The regular expression have all strings of 0's and 1's with no two consecutive 0's, is

A.
$(0 + 1)$
B.
$(0 + \epsilon) (1 + 10)^*$
C.
$(0 + 1)^*$
D.
$(0 + 1)^* 011$

Question 20

The regular expression with all strings of 0's and 1's with at least two consecutive 0's is:

A.
$1 + (10)^*$
B.
$(0 + 1)^0$
C.
$(0 + 1)^0(0 + 1)^*$
D.
$0^1$

Question 21

Which of the following is NOT the set of regular expression

R = (ab + abb)^*bbab

A.
Ababbbbab
B.
Ababbabbbbab
C.
Abbbab
D.
Abababab

Question 22

Which string can be generated by

S \rightarrow aS/bA, A \rightarrow d/cA

A.
Aabccd
B.
Abcca
C.
Adabcca
D.
Abababd

Question 23

The regular sets are closed under

A.
Union
B.
Kleene's closure
C.
Concentration
D.
All of the above

Question 24

Which of the following statement(s) is (are) wrong?

A.
The regular sets are closed under intersection
B.
The class of regular sets is closed under substitution
C.
The class of regular sets is closed under homomorphisms
D.
Context sensitive Grammar (CGS) can be recognized by Finite State Machine

Question 25

A Finite State Machine can be considered, having finite tape length without rewinding capability and unidirectional tape movement

A.
Turing machine
B.
Context free languages
C.
Pushdown automata
D.
Regular language

Question 26

Which of the following statement is wrong?

A.
A finite state machine can be considered to be a Turing Machine of finite tape length without rewinding capability and unidirectional tape movement
B.
Turing machine is more powerful than finite state machine because it has the capability to remember arbitrary long sequences of input symbol
C.
Palindromes can't be recognized by any Finite State Machine (FSM) because an FSM can't remember arbitrarily large amount of information
D.
Turing machine is more powerful than FMS because it has no final state

Question 27

Let

L

be a language recognized by a finite automaton. The reverse language

L' = \{\omega \mid \omega\text{ is the reverse of }v,\ v \in L\}

is:

A.
Regular language
B.
Context-free language
C.
Context-sensitive language
D.
Recursively enumerable language

Question 28

The Grammar

G = <{S}, {0, 1}, P, S>

Where

p

is

S \rightarrow 0SI, S \rightarrow 0S, S \rightarrow SI, S \rightarrow 0

is

A.
Recursively enumerable language
B.
Regular expression
C.
Context-sensitive language
D.
Context free language

Question 29

Any given transition graph has an equivalent

A.
Regular expression
B.
DFSM (Deterministic Finite State Machine)
C.
NDFSM
D.
All of them

Question 30

The intersection of CFL and regular language

A.
Is always regular
B.
Both (A) and (C) above
C.
Is always context-free
D.
Need not be regular

Question 31

Context-sensitive Grammar can be recognized by

A.
Deterministic pushdown Automata
B.
Non-deterministic pushdown automata
C.
Finite State Machine (FSM)
D.
Linearly Bounded Memory Machine

Question 32

Which of the following regular expression identity's are true?

A.
$r' = r$
B.
$rS' = r + S$
C.
$(r + S)' = r' + S'$
D.
All of these

Question 33

The Language

L = {0:1n2k3k \text{ where } n, k > 0}

A.
Context-sensitive language
B.
Context-free language
C.
Regular languages
D.
Recursively enumerable language

Question 34

Consider the production grammar

S \rightarrow XY/XS

\

X \rightarrow a/aX

\

Y \rightarrow b

\ Which of the following regular expressions corresponding to the production grammar?

A.
$(ab)$
B.
$a(ab)^{b}$
C.
$a^a b^b$

Question 35

Which of the following sentences is generated by production grammar?

S \rightarrow aSbX

\

X \rightarrow dccX

A.
Abblod
B.
aabccd
C.
aabd
D.
ababccd

Question 36

Consider a NDFA shown in figure below. The Automation accepts

A.
All words that contain the substring ab and end with a
B.
All words that contain the substring ba and end with a
C.
All words that end with a, but not the null string $\epsilon$
D.
All words that end with a, and also the null string

Question 37

Which of the following is accepted by deterministic pushdown machine but not accepted by non-deterministic pushdown machine (NDPDM)?

A.
Strings end with a particular alphabet
B.
All strings in which a given symbol is present at least twice
C.
Even palindrome
D.
None of these

Question 38

Consider the following grammar

X \rightarrow Xx/Yy

\

X \rightarrow Yy/Z\omega

\

Y \rightarrow y/Yw

\

Z \rightarrow y

\ Which of the regular expressions describe the same set of strings as the grammar?

A.
$x\omega y + x\omega yx + y\omega x$
B.
$x\omega y + x\omega xy + y\omega x$

Question 39

Which of the following instance of the post correspondence problem have a viable sequence?

A.
${(x, xx), (xx, xyx), (xyx, yxx), (yyxx, xyyx)}$
B.
${(yx, yxy), (xyy, yy), (yyxy, yyy)}$
C.
${(yx, yxx), (xy, yyy), (yy, y)}$
D.
None of the above

Question 40

Which of the following statement(s) is (are) correct?

A.
Recursively languages are closed under complementation
B.
If a language and its complement are both recursively enumerable then language is recursive
C.
Set of recursively enumerable language is closed under union
D.
All of these

Question 41

Consider the following FA shown in figure below. The language accepted by the FA is

A.
$(a + b)^* b$
B.
$(a + b)^* b$
C.
$a^* b$
D.
$a^* b$

Question 42

Which of the following statement is wrong

A.
Any regular language has an equivalent context-free grammar
B.
Some non-regular languages can't be generated by any context-free grammar
C.
The intersection of context free languages and a regular language is always context-free
D.
All language can be generated by CFG

Question 43

Consider a grammar

S \rightarrow SS

\

S \rightarrow 0S1

\

S \rightarrow 1S0

\

S \rightarrow \epsilon

\ The grammar will generate

A.
Regular language
B.
Context-free language
C.
Context sensitive language
D.
Recursively enumerable language

Question 44

The language constructs which are useful in describing nested structures such as balanced parenthesis

A.
Regular expression
B.
Non-context free grammars
C.
Context-free grammar
D.
None of these

Question 45

A grammar that produce more than one parse free for same sentence is called

A.
Ambiguous
B.
Regular
C.
Unambiguous
D.
None of these

Question 46

Which of the regular expression denotes a language containing all possible strings over the alphabet

{a, b}

?

A.
$a^* b^*$
B.
$(a, b)^*$
C.
$(ab)^*$
D.
$(a + b)^*$

Question 47

Palindromes can't be recognized by any Finite State Machine because

A.
An FSM can't remember arbitrarily large amount of information
B.
An FSM can't fix the mid-point
C.
FSM can't find whether the second half of the string matches the first half
D.
All of these

Question 48

A language

L

is accepted by FA if and only if it is

A.
Context-free
B.
Recursive
C.
Context sensitive
D.
Right-linear

Question 49

A language is denoted by a regular expression

L = {x^*(x/y)x}

. Which of the following is not a legal string within

L

?

A.
Yx
B.
yxx
C.
x
D.
xy xyx

Question 50

Can a DFA simulate NFA?

A.
No
B.
Sometimes
C.
Yes
D.
Depends on NFA

Practice another set Take a test on this chapter →

C.

L = {aaab, baba, bbaa, bbbb}

D.

L = {aaaa, ababa, bbaa, aaab}

B.

{S \rightarrow aS, S \rightarrow bA, A \rightarrow bB, B \rightarrow bBa, B \rightarrow bB}

C.

{S \rightarrow aaS, S \rightarrow bbA, A \rightarrow bB, B \rightarrow ba}

D.

None of the above

D.

{a^b / i, j \geq 1, i \neq j}

B.

{S \rightarrow A, S \rightarrow C, A \rightarrow aA, A \rightarrow aB, B \rightarrow aBb, B \rightarrow ab, C \rightarrow Cb, E \rightarrow Bb}

C.

{S \rightarrow A, A \rightarrow aA, A \rightarrow aB, B \rightarrow ab}

D.

None of the above

D.

a^a b

C.

x\omega y + x\omega xyx + y\omega x + y\omega x

D.

x\omega xy + x\omega \omega y + y\omega x