Computer Science Study Materials for Competitive Exams

Sample Questions, Previous Year Solved Papers, Study Materials For Competitive Examinations Like UGC NET, SET And GATE Computer Science.

Wednesday, 29 October 2014

11.       The student marks should not be greater than 100. This is
(A) Integrity constraint                        (B) Referential constraint
(C) Over-defined constraint   (D) Feasible constraint
Answer: A
12.       GO BOTTOM and SKIP-3 commands are given one after another in a database file of 30 records. It shifts the control to
(A) 28th record              (B) 27th record
(C) 3rd record                (D) 4th record
Answer: B
13.       An ER Model includes
I.  An ER diagram portraying entity types.
II. Attributes for each entity type
III. Relationships among entity types.
IV. Semantic integrity constraints that reflects the business rules about data not captured in the ER diagram.
(A) I, II, III & IV               (B) I&IV
(C) I, II & IV                    (D) I & III
Answer: A
14.       Based on the cardinality ratio and participation ............... associated with a relationship type, choose either the Foreign Key Design, the Cross Referencing Design or Mutual Referencing Design.
(A) Entity           (B) Constraints
(C) Rules          (D) Keys
Answer: B
15.       Data Integrity control uses ................
(A) Upper and lower limits on numeric data.
(B) Passwords to prohibit unauthorised access to files.
(C) Data dictionary to keep the data
(D) Data dictionary to find last access of data
Answer: B

16.       What does the following declaration mean ?
int (*ptr) [10];
(A) ptr is an array of pointers of 10 integers.
(B) ptr is a pointer to an array of 10 integers.
(C) ptr is an array of 10 integers.
(D) none of the above.
Answer: B
17.       Which of the following has compilation error in C ?
(A) int n = 32;
(B) char ch = 65;
(C) float f= (float) 3.2;
(D) none of the above
Answer: D
18.       Which of the following operators cannot be overloaded in C+ + ?
(A) *                    (B) +=
(C) ==                 (D) ::
Answer: D
19.       .................. allows to create classes which are derived from other classes, so that they automatically include some of its "parent's" members, plus its own members.
(A) Overloading           (B) Inheritance
(C) Polymorphism       (D) Encapsulation
Answer: B
20.    The correct way to round off a floating number x to an integer value is
(A) y = (int)(x+0.5)
(B) y = int(x+0.5)
(C) y = (int)x+0.5
(D) y = (int)((int)x+0.5)
Answer: A

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1.       When data and acknowledgement are sent in the same frame, this is called as
(A) Piggy packing        (B) Piggy backing
(C) Back packing         (D) Good packing
Answer: B
2.       Encryption and Decryption is the responsibility of ............... Layer.
(A) Physical                  (B) Network
(C) Application             (D) Datalink
Answer: C
3.       An analog signal carries 4 bits in each signal unit. If 1000 signal units are sent per second, then baud rate and bit rate of the signal are ............... and ..............
(A) 4000 bauds \ sec & 1000 bps
(B) 2000 bauds \ sec & 1000 bps
(C) 1000 bauds \ sec & 500 bps
(D) 1000 bauds \ sec & 4000 bps
Answer: D
Bit rate is the number of bits per second. Baud rate is the number of signal units per second. Baud rate is less than or equal to the bit rate.
Baud rate = 1000 bauds per second (baud/s)
Bit rate = 1000 x 4 = 4000 bps
4.       The VLF and LF bauds use .............. propagation for communication.
(A) Ground                    (B) Sky
(C) Line of sight           (D) Space
Answer: A
VLF (Very Low Frequency)
LF (Low Frequency)
In general there are three type of propagation.1.Ground Propagation 2.Sky propagation 3.Line-of-sight propagation.
In ground propagation, radio waves travel through the lowest portion of the atmosphere. These low-frequency signals travel in all directions from the transmitting antenna.
5.       Using the RSA public key crypto system, if p=13, q=31 and d=7, then the value of e is
(A) 101               (B) 105
(C) 103              (D) 107
Answer: C
Basic RSA Algorithm:
1. Choose two primes, p & q.
2. Compute n=p*q and z=(p-1)*(q-1).
3. Choose a number relatively prime to z and call it d.
4. Find e such that e*d=1modz.
Given p=13, q=31 & d=7, e=?
7e=1mod360, then 7e must be 361, 721, 1081, 1441, etc. Dividing each of these in turn by 7 to see which is divisible by 7, we find that 721/7 = 103, hence e = 103.

6.       FAN IN of a component A is defined as
(A) Number of components that can call or pass control to component A.
(B) Number of components that are called by component A.
(C) Number of components related to component A.
(D) Number of components dependent on component A.
Answer: A
7.       The relationship of data elements in a module is called
(A) Coupling     (B) Modularity
(C) Cohesion   (D) Granularity
Answer: C
Cohesion is the indication of the relationship within module. Coupling is the indication of the relationships between modules. While designing you should strive for high cohesion. While designing you should strive for low coupling.
8.       Software Configuration Management is the discipline for systematically controlling
(A) the changes due to the evolution of work products as the project proceeds.
(B) the changes due to defects (bugs) being found and then fixed.
(C) the changes due to requirement changes
(D) all of the above
Answer: D
9.       Which one of the following is not a step of requirement engineering ?
(A) Requirement elicitation    (B) Requirement analysts
(C) Requirement design        (D) Requirement documentation
Answer: C
10.    Testing of software with actual data and in actual environment is called
(A) Alpha testing                      (B) Beta testing
(C) Regression testing           (D) None of the above
Answer: B

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Tuesday, 28 October 2014

11.       Manager's salary details are to be hidden from Employee Table. This Technique is called as
(A) Conceptual level Datahiding
(B) Physical level Datahiding
(C) External level Datahiding
(D) Logical level Datahiding
Answer: C
12.       A Network Schema
(A) restricts to one to many relationship
(B) permits many to many relationship
(C) stores Data in a Database
(D) stores Data in a Relation
Answer: B
13.       Which normal form is considered as adequate for usual database design?
(A) 2NF              (B) 3NF
(C) 4NF             (D) 5NF
Answer: B
14.       If D1, D2,…. Dn are domains in a relational model, then the relation is a table, which is a subset of
(A) D1+D2+…. +Dn
(B) D1x D2x… xDn
(C) D1U D2U….UDn
(D) D1- D2-….-Dn
Answer: B
15.       Which of the following addresses is used to deliver a message to the correct application program running on a host?
(A) Port              (B) IP
(C) Logical        (D) Physical
Answer: A

16.       In substitution, a character in the plaintext is always changed to the same character in the ciphertext, regardless of its position in the text.
(A) polyalphabetic       (B) monoalphabetic
(C) transpositional       (D) multialphabetic
Answer: B
17.       In classful addressing, the IP address belongs to
(A) Class A       (B) Class B
(C) Class C       (D) Class D
Answer: B
18.       In hierarchical routing with 4800 routers, what region and cluster sizes should be chosen to minimize the size of the routing table for a three layer hierarchy?
(A) 10 clusters, 24 regions and 20 routers
(B) 12 clusters, 20 regions and 20 routers
(C) 16 clusters, 12 regions and 25 routers
(D) 15 clusters, 16 regions and 20 routers
Answer: D
Rooters minimum, then regions minimum, then clusters minimum.
19.       In IPv4 header, the field is needed to allow the destination host to determine which datagram a newly arrived fragment belongs to.
(A) identification          (B) fragment offset
(C) time to live              (D) header checksum
Answer: A
20.    Given L1 = L(a*baa*) and L2 = L(ab*)
The regular expression corresponding to language L3 = L1/L2 (right quotient) is given           by
(A) a*b               (B) a*baa*
(C) a*ba*           (D) None of the above
Answer: C

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1.       COCOMO stands for
(A) COmposite COst MOdel
(B) COnstructive COst MOdel
(C) COnstructive COmposite MOdel
(D) COmprehensive COnstruction MOdel
Answer: B
The Constructive Cost Model (COCOMO) is an algorithmic software cost estimation model.
2.       Match the following:
a. Good quality     i. Program does not fail for a specified time in a given environment
b. Correctness     ii. Meets the functional requirements
c. Predictable      iii. Meets both functional and non-functional requirements
d. Reliable          iv. Process is under statistical control
      a   b  c  d
(A) iii  ii   iv  i
(B) ii   iii  iv  i
(C) i    ii  iv  iii
(D) i    ii  iii  iv
Answer: A
3.       While estimating the cost of software, Lines of Code (LOC) and Function Points (FP) are used to measure which one of the following?
(A) Length of code                  (B) Size of software
(C) Functionality of software (D) None of the above
Answer: B
4.       A good software design must have
(A) High module coupling, High module cohesion
(B) High module coupling, Low module cohesion
(C) Low module coupling, High module cohesion
(D) Low module coupling, Low module cohesion
Answer: C
5.       Cyclometric complexity of a flow graph G with n vertices and e edges is
(A) V(G) = e+n-2
(B) V(G) = e-n+2
(C) V(G) = e+n+2
(D) V(G) = e-n-2
Answer: B

6.       When the following code is executed what will be the value of x and y?
int x = 1, y=0;
y = x++;
(A) 2, 1               (B) 2, 2
(C) 1, 1               (D) 1, 2
 Answer: A
7.       How many values can be held by an array A(-1,m;1 ,m) ?
(A) m                  (B) m2
(C) m(m+l)         (D) m(m+2)
Answer: D
Total number of values =m(m+2). Because -1 to m, m+2 values and 1 to m, m values
8.       What is the result of the expression
(1&2)+(3/4) ?
(A) 1       (B) 2
(C) 3       (D) 0
Answer: D
9.       How many times the word 'print' shall be printed by the following program segment?
for(i=1, i≤2, i++)
for(j=1, j≤2, j++)
for(k=1, k≤2, k++)
(A) 1       (B) 3
(C) 6       (D) 8
Answer: D
10.    Which of the following is not a type of Database Management System?
(A) Hierarchical                        (B) Network
(C) Relational               (D) Sequential
Answer: D

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