UGC NET Computer Science Solved Paper II JUNE 2007


  1. The following deterministic finite automata recognizes:

(A) Set of all strings containing ‘ab’

(B) Set of all strings containing ‘aab’

(C) Set of all strings ending in ‘abab’

(D) None of the above

Answer: D


  1. Depth ion travels of the following directed graph is:

(A) ABCDEF     (B) ABDEFC

(C) ACEBDF    (D) None of the above

Answer: B


  1. The maximum number of nodes in a binary tree of depth 10 is:

(A) 1024                        (B) 210-1

(C) 1000                        (D) None of the above

Answer: B


  1. The regular expression given below describes:

r=(1+01)*(0+λ)

(A) Set of all string not containing ‘11’

(B) Set of all string not containing ‘00’

(C) Set of all string containing ‘01’

(D) Set of all string ending in ‘0’

Answer: D


  1. Which of the following language is regular?

(A) L={anbn|n≥1}

(B) L={anbmcndm|n,m≥1}

(C) L={anbm|n,m≥1}

(D) L={anbmcn|n,m≥1}

Answer: C


  1. 2’s complement of -100 is:

(A) 00011100               (B) 10011101

(C) 10011100               (D) 11100100

Answer: C


  1. Which of the following expression remove hazard form: xy+zx’ ?

(A) xy+zx’          (B) xy+zx’

(C) xy+zx’+yz    (D) xy+zx’+wz

Answer: C


  1. How many 1’s are present in the binary representation of 15×256+5×16+3:

(A) 8       (B) 9

(C) 10     (D) 11

Answer: A


  1. If A⊕B=C, then:

(A) A⊕C=B                   (B) B⊕C=A

(C) A⊕B⊕C=1                        (D) A⊕B⊕C=0

Answer: A,B,D


  1. What is the maximum counting speed of a 4-bit binary counter which is composed of Flip-Flop with a propagation delay of 25ns?

(A) 1MHz           (B) 10MHz

(C) 100MHz      (D) 4MHz

Answer: B


  1. The following loop in ‘C’:

int i=0;

While(i++<0)i–;

(A) will terminate

(B) will go into an infinite loop

(C) will give compilation error

(D) will never be executed

Answer: B


  1. In case of right shift bitwise operator in ‘C’ language, after shifting n bits, the left most n bits:

(A) are always filled with zeroes

(B) are always filled with ones

(C) are filled with zeroes or ones and is machine dependent

(D) none of the above

Answer: C


  1. What keyword in class specification helps to hide data:

(A) Public          (B) Private

(C) Static           (D) Void

Answer: B


  1. What is the output of the following ‘C’ program?

main()

{printf(“%x”,-1>>4);}

(A) ffff                (B) 0fff

(C) 0000                        (D) fff0

Answer: A

Explanation

P2 2007 June UGC net


  1. Runtime polymorphism can be achieved by:

(A) Accessing virtual function through the pointer of the base class

(B) Accessing virtual function through the object

(C) The derived class

(D) None of these

Answer: A


  1. Which of the following statements is wrong?

(A) 2-phase Locking Protocols suffer from deadlocks

(B) Time-Stamp Protocols suffer from more aborts

(C) Time-Stamp Protocols suffer from cascading roll back where as 2-Phase locking Protocol do not

(D) None of these

Answer: C


  1. A recursive foreign key is a:

(A) references a relation                   

(B) references a table

(C) references its own relation         

(D) references a foreign key

Answer: C


  1. A sub class having more than one super class is called:

(A) Category                 (B) Classification

(C) Combination          (D) Partial Participation

Answer: A


  1. A relation R={A,B,C,D,E,F} is given with following set of functional dependencies:

F={A→B,AD→C,B→F,A→E}. Which of the following is Candidate Key?

(A) A                   (B) AC

(C) AD               (D) None of these

Answer: C


  1. Which statement is false regarding data independence?

(A) Hierarchical data model suffers from data Independence

(B) Network model suffers from data Independence

(C) Relational model suffers only from logical data Independence

(D) Relational model suffers only from physical data Independence

Answer: C


  1. The time required to find shortest path in a graph with n vertices and e edges is:

(A) O(e)              (B) O(n)

(C) O(e2)            (D) O(n2)

Answer: D


  1. Pre order is also known as:

(A) Depth first order                 (B) Breadth first order

(C) Topological order              (D) Linear order

Answer: A


  1. The equivalent post fix express for d/(e+f) + b*c is:

(A) defbc/++                  (B) def+/bc+*

(C) def+/bc*+                (D) None of these

Answer: C


  1. Which algorithm has same average, worst case and best case time?

(A) Binary search        (B) Maximum of n numbers

(C) Quick sort               (D) Fibonacci search

Answer: B


  1. Application of data structure in queue is:

(A) Level wise printing of tree

(B) Implementation of priority queues

(C) Function call implementation

(D) Depth first search in a graph

Answer: B


  1. In case of Bus/Tree topology signal balancing issue is overcome by:

(A) Strong Transmitter                        (B) Polling

(C) Segmentation                    (D) Modulation

Answer: C


  1. Which of the following techniques are used to control data flow?           1. Windowing   2. Routing     3. RPCs         4. Buffering

(A) 1, 4               (B) 2, 3, 4

(C) 1, 3, 4          (D) 1, 2, 3, 4

Answer: A


  1. TDM is …………….

(A) A primary/secondary type protocol

(B) A peer/peer protocol

(C) A Non-priority peer/peer protocol

(D) A priority type protocol

Answer: C


  1. What services does the Internet Layer provide?
  2. Quality of service                2. Routing
  3. Addressing                           4. Connection-oriented delivery
  4. Framing bits

(A) 1, 2, 3                       (B) 2, 3, 4

(C) 1, 3, 4, 5                  (D) 2, 3, 4, 5

Answer: A


  1. Which of the following protocols is used to prevent looping?

(A) OSPF                      (B) Spanning tree

(C) SRB                         (D) Fragment free switching

Answer: B


  1. The parsing technique that avoids back tracking is:

(A) Top-down parsing            

(B) Recursive-descent parsing

(C) Predictive                          

(D) Syntax tree

Answer: C


  1. A Top-down Parse generates:

(A) Right-most derivation                  

(B) Right-most derivation in reverse

(C) Left-most derivation                     

(D) Left-most derivation in reverse

Answer: C


  1. In an absolute loading scheme, which loader function is accomplished by programmer?

(A) Allocation               (B) Linking

(C) Reallocation          (D) Both (A) and (B)

Answer: D


  1. Symbol table can be used for:

(A) Checking type compatibility

(B) Suppressing duplication of error message

(C) Storage allocation

(D) All of these above

Answer: D


  1. Moving process from main memory to disk is called:

(A) Caching                  (B) Termination

(C) Swapping               (D) Interruption

Answer: C


  1. Part of a program where the shared memory is accessed and which should be executed indivisibly, is called:

(A) Semaphores                      (B) Directory

(C) Critical Section                  (D) Mutual exclusion

Answer: C


  1. Windows is a ……………… operating system.

(A) Non pre-emptive                (B) Pre-emptive

(C) Multi-user                           (D) Real time

Answer: C


  1. The “nice” command is used in Unix:

(A) to decrease the priority of a process

(B) to increase the priority of a process

(C) to get the highest priority

(D) nothing to do with the priorities

Answer: A, B

Explanation:

For Increase or decrease the priority of a job/Process we use Nice command, and its range -19 to 20.

If we need to increase the priority then we needs to decrease the priority number

If we need to decrease the priority then we needs to increase the priority number

Ex:- Nice -n 10 <cmd>


  1. Which page replacement policy suffers from Belady’s anomaly?

(A) LRU             (B) LFU

(C) FIFO            (D) OPTIMAL

Answer: C


  1. Cache memory is:

(A) High Speed Register        (B) Low-Speed RAM

(C) Non-Volatile RAM             (D) High-Speed RAM

Answer: D


  1. Which of the following combination is preferred with respect to cohesion and coupling?

(A) low and low                        (B) low and high

(C) high and low          (D) high and high

Answer: C


  1. Difference between flow-chart and data-flow diagram is:

(A) there is no difference

(B) usage in high level design and low level design

(C) control flow and data flow

(D) used in application programs and system programs

Answer: C


  1. Match the following:

(a) Unit test                   (i) Requirements

(b) System test             (ii) Design

(c) Validation test         (iii) Code

(d) Integration test       (iv) System Engineering

Which of the following is true?

         (a)     (b)      (c)    (d)

(A)   (ii)     (iii)      (iv)    (i)

(B)   (i)      (ii)       (iv)   (iii)

(C)   (iii)    (iv)      (i)     (ii)

(D)   None of the above

Answer: D


  1. Problems with waterfall model are:     1. Real projects rarely follow this model proposes.                                      2. It is often difficult for the customer.                                3.Working model is available only in the end.                                                4. Developers are delayed unnecessarily

Which of the following is true?

(A) 1 and 4 only           (B) 2 and 3 only

(C) 1, 2 and 3 only       (D) 1, 2, 3 and 4

Answer: D


  1. Which one of the following is a object-oriented approaches:

(A) The Booch method                      

(B) The Rumbaugh method

(C) The Coad and Yomdon method

(D) All of the above

Answer: D


  1. Which technical concept sets cellular apart from all preceding mobile/radio systems?

(A) FM-Transmission             

(B) Duplex Functionality

(C) Frequency Reuse            

(D) TDMA Technology

Answer: D


  1. Wireless interconnections to the PSTN are also known as:

(A) Localities                (B) CLECs

(C) POPs                       (D) IXCs

Answer: C


  1. Dimensional modeling  in Data mining refers to:

(A) view and interrogate data                       

(B) define structures and store data

(C) retrieve information only

(D) none of these

Answer: A


  1. The U-NII(Unlicensed National Information Infrastructure) band operates at the …………. frequency.

(A) 2.4 GHz       (B) 33 MHz

(C) 5 GHz          (D) 16 GHz

Answer: C


  1. Which digital radio technology employs an N=1 frequency-reuse plan?

(A) GSM                        (B) TDMA

(C) D AMPS                  (D) CDMA

Answer: D