__UGC NET Previous Year Papers__

__Computer Science Paper II __

__June-2010 __

**1. **“*x*^{1} is a clone of *x*” means *x*^{1} is identical to *x *in terms of the physical attributes namely, height, weight and complexion. Given, height, weight and complexion only form a complete set of attributes for an entity, cloning is an equivalence relation. What is your impression about this statement ?

**(A)** The statement is true

**(B)** The statement is false

**(C)** The truth value of the statement cannot be computed

**(D)** None of these

**Ans: (A)**

**2. ** ‘R is a robot of M’ means R can perform some of the tasks that otherwise M would do and R is unable to do anything else. Which of the following is the most appropriate representation to model this situation ?

**Ans: (-)**

**3. ** “My Lafter Machin (MLM) recognizes the following strings :

**(i)** a

**(ii)** aba

**(iii)** abaabaaba

**(iv)** abaabaabaabaabaabaabaabaaba

Using this as an information, how would you compare the following regular expressions?

**(i) **

**(ii)**

**(iii)**

**(A)** (ii) and (iii) are same, (i) is different.

**(B)** (ii) and (iii) are not same.

**(C)** (i), (ii) and (iii) are different.

**(D)** (i), (ii) and (iii) are same.

**Ans: (D)**

**4. ****S _{1}** : I teach algorithms and maths.

**S _{2}** : My professor teaches maths, electronics and computer science.

**S _{3}** : I have a student of maths.

**S _{4}** : Algorithm is a part of computer science.

**S _{5}** : Maths students know computer science.

What would be the chromatic number of a graph, vertices of which are the actors/entities that are involved in the sentences S_{1} to S_{5} and edges-to represent the associations/relationships amongst the entities/actors as expressed in the sentences S_{1} to S_{5} above?

**(A)** 2

**(B)** 3

**(C)** 4

**(D)** None of these

**Ans: (-)**

**5. ** For your ATM debit card, you have a 4-decimal-digit personal secret code. In the absence of any clue, a brute-force attack takes time-‘t’ to crack the code on an ATM terminal. Therefore ‘t’ is the secure-time for a customer to report in case the card is misplaced. Your Bank has decided to facilitate an increased secure-time. Out of the following, which option should provide the largest rise in the value of ‘t’ ?

**(A)** Instead of 4-decimal-digits, maintain the personal secret code in 4-hexadecimal-digits.

**(B)** Instead of 4-decimal digits, maintain a 5-decimal-digit personal secret code.

**(C)** Reduce the processing speed of the ATM terminals to the half of their current speed.

**(D)** None of the above provides any improvement.

**Ans: (B)**

**6. ** The logic expression for the output of the circuit shown in the figure is

**Ans: (C)**

**7. ** Advantage of synchronous sequential circuits over asynchronous ones is

**(A)** faster operation

**(B)** ease of avoiding problems due to hazard

**(C)** lower hardware requirement

**(D)** better noise immunity

**Ans: (A)**

**8. ** What is the transitive voltage for the voltage input of a CMOS operating from 10V supply?

**(A)** 1V

**(B)** 2V

**(C)** 5V

**(D)** 10 V

**Ans: (C)**

**9. ** What is decimal equivalent of BCD 11011.1100 ?

**(A)** 22.0

**(B)** 22.2

**(C)** 20.2

**(D)** 21.2

**Ans: (B)**

**10. ** The function represented by the kmap given below is

**Ans: (-)**