Kerala Plus One Computer Science Question Paper March 2023 with Answers

Reviewing Kerala Syllabus Plus One Computer Science Previous Year Question Papers and Answers Pdf March 2023 helps in understanding answer patterns.

Kerala Plus One Computer Science Previous Year Question Paper March 2023

Time: 2 Hours
Total Score: 60 Marks

Answer any 5 questions from 1 to 6. Each carries 1 score. (5 × 1 = 5)

Question 1.
The number (158)₁₀ can be represented in Hexadecimal number system as ____________ .
Answer:
(9E)₁₆

Question 2.
Some of the components in the phases of programming are given below. Write them in order of their occurrence:
(i) Translation
(ii) Documentation
(iii) Problem identificaiton
(iv) Coding of program
Answer:
Problem Identification, Coding of a program, Translation, Documentation.

Question 3.
The memory size of ‘double’ data type in C++ is ……………….. bytes.
Answer:
8 bytes

Question 4.
In C++, name the loop which can be used to ensure that the body of the loop will surely be executed at least once.
Answer:
do while loop

Question 5.
Any device which is directly connected to a network is generally known as ___________ .
Answer:
node

Question 6.
Pick the odd one from the following list:
(i) Spam
(ii) Trojan horse
(iii) Phishing
(iv) Firewall
Answer:
firewall

Answer any 9 questions from 7 to 18. Each carries 2 scores. (9 × 2 = 18)

Question 7.
If (x)₈ = (101011)₂ = (y)₁₆ find the values of x and y.
(a) Temperature
(b) Pressure
(c) Frequency
(d) Wavelength
Answer:
x = 53 and y = 2B.

Question 8.
Write the following memory devices in the order of their speed. (Fastest to slowest order):
(a) Cache
(b) RAM
(c) Hard Disk
(d) Registers
Answer:
Registers , Cache, RAM, Hard Disk.

Question 9.
Define syntax error and logical error.
Answer:
Syntax error – If the programmer makes any mistakes in syntax. Eg. 5 = x instead of x = 5;
Logical error – If the programmer makes any logical mistakes.

Question 10.
Find the invalid identifier names from the following:
Answer:
d-w: It is invalid because special character hyphen is used.
999: It is invalid because it is a number.
Z$: It is invalid because special character $ is used.
8c – It is invalid because it is started with a number.

Question 11.
Write the symbols of the following C++ operators :
(a) Conditional operator
(b) Extraction operator
(c) Modulus operator
(d) NOT operator
Answer:
a) ?:
b) >>
c) %
d) !

Question 12.
Rewrite the following C++ program code with switch statement:
if (val= =1)
cout<<“Science”;
else if (val= =5)
cout<<“Computer Science”:
else
cout<<“Not a course”;
Answer:

switch(val)
{
case 1 : cout<<“Science”;
case 5: cout<<“Computer Science”;
default: cout<<“Not a course”;
}

Question 13.
(i) An array is declared as follows:
int a[5] = {1, 2, 3, 4, 5};
What will be the value of a [2] + a [3]?
(ii) How many bytes are allocated by the above array in memory?
Answer:
(i) Here a[2] = 3 and a[3] = 4, so 3 + 4 = 7.
(ii) 4 bytes for an integer so 5*4 = 20 bytes.

Question 14.
Compare Linear search and Binary search on arrays in C++
Answer:

Linear	Binary
No need of sorted array.	Need of sorted array.
Searching is slower for larger array.	It is faster.
It starts checking from the first element and checks all elements.	Divide and conquer method used.

Question 15.
Construct the function prototypes for the following functions:
(i) The function Display () accepts one argument of type double and does not return any value. (1)
(ii) Total () accepts two arguments of type into, float respectively and return a float type value. (1)
Answer:
(i) void Display(double);
(ii) float Total(int, float);

Question 16.
Briefly explain about different types of methods used for passing arguments’to a function.
Answer:
Methods of calling functions
Two types call by value and call by reference.

1. Call by value: In call by value method the copy of the original value is passed to the function, if the function makes any change will not affect the original value.
2. Call by reference: In call by reference method the address of the original value is passed to the function, if the function makes any change will affect the original value.

Question 17.
Discuss the difference in working methods of hub and switch.
Answer:
Hub: It is a small, simple and inexpensive device used to connect computers(devices) to a network. If a computer wants to transmit data to another computer. First it sends to the hub, the hub retransmits this data to all other computers. Each and every computer gets the data and check whether it is for them or not. It increases the network traffic and hence the transmission speed is low.

Switch: It is an expensive device used to connect computers(devices) to a network. Unlike hub, switch transmit data not to all computers, it retransmits data only to the intended computer. So the traffic is less and speed is high.

Question 18.
(i) Write a note on search engines.
(ii) What is meant by Phishing?
Answer:
(i) Search engines
By using search engines we will get a variety of information. It is a-newly developed tool that helped to search the information on the internet more effectively and easily. Search engines are programs that help people to locate information from crores of website on internet using a database that consists of references. Users can interact with the search engine through the home page of the search engine. To get the information about artificial intelligence just type this in the box provided for it and click the search button. Search engines searches by using a particular search algorithm then displays the matching documents or web addresses. Search engine use soft wares called spiders or bots to search documents and their web addresses. Spiders search the internet using the directions given by the search engines and prepare an index and stores it in a database. The searching algorithm searched this database when the users submits a request and create a web page displaying the matching results as hyperlinks.
Eg: Google, Yahoo, Rediff etc.

(ii) Phishing (Fishing): It is an attempt to get others information such as usenames, passwords, bank a/c details etc by acting as the authorized website. Phishing websites have URLs and home pages similar to their original ones and mislead others, it is called spoofing.

Answer any 9 questions from 19 to 29. Each carries 3 scores. (9 × 3 = 27)

Question 19.
(i) Name the technology used in third generation of computers. (1)
(ii) Draw the John Von Neumann Architecture for functional iHnits of a computer. (2)
Answer:
(i) Integrated Circuit(IC)

Question 20.
Which gates are called universal gates? Draw their symbols.
Answer:
NAND and NOR are called universal gates.
NAND gate
The output of AND gate is inverted by NOT gate is the NAND gate

In short the NAND gate is as shown below

NOR gate
The output of OR gate is inverted by NOT gate is the NOR gate.

In short the nor gate is shown below

Question 21.
(i) How e-Waste create environmental and health problems? (1)
(ii) Name the different methods for e-Waste disposal. (2)
Answer:
(i) It contains poisonous substances such as lead, mercury, cadmium etc and may cause diseases if not properly managed.

(ii) e-Waste disposal methods
a) Reuse: Reusability has an important role of e-Waste management and can reduce the volume of e-Waste
b) Incineration: It is the process of burning e. Waste at high temperature in a chimney
c) Recycling of e-Waste: It is the process of making new products from this e-Waste.
d) Land filling: It is used to level pits and cover by thick layer of soil.

Question 22.
Draw a flowchart to find the sum of first 10 natural numbers.
Answer:

Question 23.
What is meant by Literals in C++? Explain its types.
Answer:
Literals (Constants): Its value does not change during execution
1) Integer literals :- Whole numbers without fractional parts are known as integer literals, its value does not change during execution. There are 3 types decimal, octal and hexadecimal.
Eg. For decimal 100, 150, etc
For octal 0100, 0240, etc
For hexadecimal 0 × 100, 0 × 1 A, etc

2) Float literals A number with fractional parts and its value does not change during execution is called floating point literals.
Eg. 3.14157, 79.78,etc

3) Character literal-: A valid C++ character enclosed in single quotes, its value does not change during execution.
Eg. ‘m’, ‘f ’ etc

4) String literal:- One or more characters enclosed in double quotes is called string constant. A string is automatically appended by a null character(‘\0’)
Eg. “Mary’s”,”India”,etc

Question 24.
(i) What is the use of keyword ‘const’ in C++?
(ii) List the different data type modifiers in C++.
Answer:
(i) It is used to declare symbolic constants.
Eg. const float pi=3.14;
(ii) short, long, signed and unsigned.

Question 25.
Briefly explain different types of type conversions in C++.
Answer:
Type conversions are of two types.
1) Implicit type conversion-: This is performed by C++ compiler internally. C++ converts all the lower sized data type to the highest sized operand. It is known as type promotion. Data types are arranged lower size to higher size is as follows.
unsigned int(2 bytes), int(4 bytes),long (4 bytes); unsigned long (4 bytes), float(4 bytes), double(8 bytes), long double(10 bytes)

2) Explicit type conversion -: It is known as type casting. This is done by the programmer. The syntax is given below.
(data type to be converted) expression
Eg. int x=10;
(float) x; This expression converts the data type of the variable from integer to float.

Question 26.
Briefly explain any three jump statements.
Answer:
1. goto statementBy using goto we can transfer the control anywhere in the program without any condition. The syntax is goto label;
Eg.

#include<iostream>
using namespace std;
int main()
{
float a, b;
cout<<"Enter 2 numbers";
cin>>a>>b;
if(b==0)
goto end;
cout<<''The quotient is "<<a/b;
return 0; ,
end:cout<<"Division by zero error";
}

2. break statement:- It is used to skip over a part of the code i.e. we can premature exit from a loop such as while, do-while, for or switch.

Syntax :
while (expression)
{
if (condition)
break;
}
Eg.
#include<iostream>
using namespace std;
main()
{
int i=1;
while(i<10)
{
cout<<i<<endl;
if(i==5)
break;
i++;
}
} The output is
1
2
3
4
5

3. continue statement:- It bypasses one iteration of the loop.

Syntax :
while (expression)
{
if (condition)
break;
}
Eg.
#include<iostream>
using namespace std;
main()
{
int i=0;
while(i<10)
{
i++;
if(i==5) continue;
cout<<i<<endl;
}
}
The output is
1
2
3
4
6
7
8
9
10

3. exit(0) functionIt is used to terminate the program. For this the header file cstdlib must be included.

Question 27.
(i) How many bytes are required to store the string “WELCOME ALL”? (1)
(ii) What is the limitation of cin>> operator while reading a string? How can we overcome it? (2)
Answer:
(i) 12 bytes(lncluding null character).
(ii) cin reads only the characters upto the space. gets() can be used to resolve this problem

Question 28.
Explain any three network topologies with figures.
Answer:
Topology: The way in which the nodes are physically interconnected to form a network.
• Bus topology
• Star topology
• Ring topology
• Mesh topology
Bus topology- In bus topology all the nodes are connected to a main cable called bus. A small device called a terminator is attached to each end of the bus.

Star topology- In star topology each node is directly connected to a hub switch.

Ring topology -In ring topology all nodes are connected using a cable that shapes like a ring or circle Data travels only in one direction in a ring.

Mesh topology- In mesh topology every node is connected to other nodes.’There will be more than one path between two nodes.

Question 29.
What is the role of Firewall and Anti-virus scanner in computer networks?
Answer:
Firewall: It is a system that controls the incoming and out going network traffic by analyzing the data and then provides security to the computer network in an organization from other network (internet).

Antivirus scanners: It is a tool used to scan computer files for viruses, worms and Trojan horses and cure the infected system. If any fault found it stops the file from running and stores the file in a special area called Qua

Answer any 2 questions from 30 to 32. Each carries 5 scores. (2 × 5 = 10)

Question 30.
(i) Write about any two methods of representing characters in memory. (2)
(ii) Draw a logic circuit for Bollean expression (\(\overline{\mathrm{A}}\) + BC) + AB (3)
Answer:
(i) Representation of characters.
1) ASCII(American Standard Code for Information Interchange) : It is 7 bits code used to represent alphanumeric and some special characters in computer memory. It is introduced by U.S. government. Each character in the key board has a unique number. Eg: ASCII code of ‘a’ is 97, when you press ‘a’ in the key board, a signal equivalent to 1100001 (Binary equivalent of 97 is 1100001) is passed to the computer memory. 2⁷ = 128, hence we can represent only 128 characters by using ASCII. It is not enough to represent all the characters of a standard keyboard.

2) EBCDIC(Extended Binary Coded Decimal Interchange Code): It is an 8 bit code introduced by IBM(lnternational Business Machine). 2⁸=26 characters can be represented by using this.

Question 31.
(i) Define Operating System. Write any two functions of operating system. (2)
(ii) Write notes on different types of language processors. (3)
Answer:
(i) Operating System: It is collection of programs which acts as an interface between user and computer. Without an operating system computer cannot do anything. Its main function is make the computer usable and use hardware in an efficient manner, eg:- Windows XP, Windows Vista, Linux, Windows 7, etc.

Major functions of an operating System

1. Process management: It includes allocation and de allocation of processes(program in execution) as well as scheduling system resources in efficient manner
2. Memory management: It takes care of allocation and de allocation of memory in efficient manner

(ii) The different language processors are given below

1. Assembler: This converts programs written in assembly language into machine language.
2. Interpreter: This converts a HLL program into machine language by.converting and executing it line by line. The first line is converted if there is no error it will be executed otherwise you have to correct it and the second line and so on.
3. Compiler: It is same as interpreter but there is a difference it translate HLL program into machine language by converting all the lines at a time. If there is no error then only it will executed.

Question 32.
(i) Explain the difference, between entry controlled loop and exit controlled loop. (3)
Entry controlled loop, exit controlled loop (3)
(ii) Classify the following loops into entry controlled loop and exit controlled loop for loop, while loop, do while loop. (2)
Answer:
i)

Entry controlled	Exit controlled
Eg. For an while	Do while
The body will be executed only if the test expression becomes true.	But here the body executes at least once even if the conditions is false
Minimum number of execution may be zero	Here it is one

ii)

Entry Controlled	Exit Controlled
For loop	Do while loop
While loop