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Students can Download Chapter 4 Getting Started with C++ Questions and Answers, Plus One Computer Application Chapter Wise Questions and Answers helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Computer Application Chapter Wise Questions Chapter 4 Getting Started with C++

Plus One Computer Application Getting Started with C++ 1 Mark Questions and Answers

Question 1.
IDE means _______.
Answer:
Integrated Development Environment

Question 2.
We know that C++ is a high level language. From the following which statement is true.
a) C++ contains English like statements.
b) C++ contains mnemonics
c) C++ contains only 0 and 1
d) None of these
Answer:
a) C++ contains English like statements.

Question 3.
C++ is a language ______.
a) High level
b) Low level
c) Middle level
d) None of these
Answer:
a) High level

Question 4.
C++ was developed at ______.
a) AT & T Bell Laboratory
b) Sanjose Laboratory
c) Kansas University Lab
d) None of these
Answer:
a) At & T Bell Laboratory

Question 5.
C ++ is a successor of ______ language.
a) C#
b) C c
c) Java
d) None of these
Answer:
b) C c

Question 6.
The most adopted and popular approach to write programs is ______.
Answer:
Structured programming

Question 7.
From the following which uses OOP concept _____.
a) C
b) C++
c) Pascal
d) Fortran
Answer:
b) C++

Question 8.
______ is the smallest individual unit
Answer:
Token

Question 9.
Pick the odd one out:
a) float
b) void
c) break
d) Alvis
Answer:
d) Alvis, the others are keywords.

Question 10.
Reserved words for the compiler is _______.
a) Literals
b) Identifier
c) Key words
d) None of these
Answer:
c) Key words

Question 11.
Pick an identifier from the following
a) auto
b) age
c) float
d) double
Answer:
b) age

Question 12.
Pick the invalid identifier
a) name
b) Date of birth
c) age
d) joining time
Answer:
b) Date of birth, because it contains space.

Question 13.
Pick the octal integer from the following
a) 217
b) 0x217
c) 0217
d) None of these
Answer:
c) 0217, an octal integer precedes

Question 14.
Pick the hexa decimal integer from the following
a) 217
b) 0x217
c)0217
d) None of these
Answer:
b) 0x217, an hexa decimal integer precedes Ox

Question 15.
From the following pick a character constant
a)’A’
b)’ALL’
c)’AIM’
d) None of these
Answer:
a) ‘A’, a character enclosed between single quote

Question 16.
Non graphic symbol can be represented by using ______.
Answer:
Escape Sequence

Question 17.
Manish wants to write a program to produce a beep sound. Which escape sequence is used to get an alert (sound)
a) \a
b) \d
c) \s
d)None of these
Answer:
a)\a

Question 18.
Ajo wants to print a matter in a new line. Which escape sequence is used for this?
a) \a
b) \n
c) \s
d)None of these
Answer:
b)\n

Question 19.
To represent null character ____ is used.
a) \n
b) \0
c) \f
d) \s
Answer:
b)\0

Question 20.
State True/ False a string is automatically appended by a null-character.
Answer:
True

Question 21.
From the following pick a string constant .
a) ‘a’
b) “abc”
c) ‘abc’
d) None of these
Answer:
“abc”, a character constant must be enclosed between double quotes.

Question 22.
C++ was developed by ______.
a) Bjarne stroustrup
b) James Gosling
c) Pascal
d) None of these
Answer:
a) Bjarne stroustrup

Question 23.
From the following which is not a character constant.
а) ‘c’
b) ‘e’
c) ‘d’
d) “c”
Answer:
d) “c”, It is a string constant the others are character constant.

Question 24.
From the following which is a valid declaration.
а) int 91;
b) int x;
c) int 9x;
d) int “x”;
Answer:
b) intx

Question 25.
Symbols used to perform an operation is called _____.
a) Operand
b) Operator
c) Variable
d) None of these
Answer:
b) Operator

Question 26.
Consider the following
C = A + B. Here A and B are called ______.
a) Operand
b) Operator
c) Variable
d) None of these
Answer:
b) Operand

Question 27.
The execution of a program starts at ______ function.
Answer:
main( )

Question 28.
The execution of a program ends with ______ function.
Answer:
main( )

Question 29.
______ is used to write single line comment.
a) //
b) P
c) */
d) None of these
Answer:
a) //

Question 30.
const k=100 means
a) const float k=100
b) const double k=100
c) const int k=100
d)const char k=100
Answer:
c) const int k=100

Question 31.
Qn. 31 ,
Each and every statement in C++ must be end with ______.
a) Semi colon
b) Colon
c) full stop
d) None of these
Answer:
a) Semi colon

Question 32.
From the following select the input operator.
a)>>
b)<< c) >
d) <
Answer:
a)>>

Question 33.
From the following select the output operator.
a)>>
b)<<
c) >
d) <
Answer:
b)<<

Question 34.
From the following which is known as string terminator.
a) ‘\0’
b) ‘\a’
c) ‘\s’
d) ‘\t’
Answer:
a) ‘\0’

Question 35.
Adeline wrote a C++ program namely sum.cpp and she compiled the program successfully with no error. Some files are generated. From the following which file is a must to run the program .
a) sum.exe
b) sum.obj
c) sum.vbp
d) sum.htm
Answer:
a) sum.exe

Question 36.
Adeline wrote a C++ program namely sum.cpp and she compiled the program successfully with no error. Some files are generated namely sum.obj and sum.exe. From this which file is not needed to run the program.
Answer:
sum.obj is not needed and can be deleted.

Question 37.
From the following which is ignored by the compiler.
а) statement
b) comments
c) loops
d) None of these
Answer:
b) comments

Question 38.
To write a C++ program, from the following which statement is a must _____.
a) sum( )
b) main( )
c) #include
d) #include
Answer:
b) main( ).
A C++ program must contains at least one main( ) function.

Question 39.
State True / False .
Comment statements are ignored by the compiler.
Answer:
True .

Question 40
More-than one input / output operator in a single statement is called ________.
Answer:
Cascading of I/O operator

Question 41.
Is 0x85B a valid integer constant in C++? If yes why ?
Answer:
Yes. It is a hexa decimal number

Plus One Computer Application Getting Started with C++ 2 Marks Questions and Answers

Question 1.
Mr. Dixon declared a variable as follows int 9age. Is it a valid identifier. If not briefly explain the rules for naming an identifier.
Answer:
It is not a valid identifier because it violates the rule
1. The rules for naming an identifier is as follows.
1) It must be start with a letter(alphabet)
2) Under score can be considered as a letter
3) White spaces and-special characters cannot be used.
4) Key words cannot be considered as an identi-fier

Question 2.
How many bytes used to store ‘\a’.
Answer:
To store ‘\a’ one byte is used because it is an escape sequence. An escape sequence is treated as one character. To store one character one byte is used.

Question 3.
How many bytes used to store “\abc”.
Answer:
A string is automatically appended by a null character.
Here one byte for \a (escape sequence).
One byte for character b.
One byte for character c.
And one byte for null character.
So a total of 4 bytes needed to store this string.

Question 4.
How many bytes used to store “abc”.
Answer:
A string is automatically appended by a null character.
Here one byte for a.
One byte for character b.
One byte for character c.
And one byte for null character.
So a total of 4 bytes needed to store this string.

Question 5.
Consider the following code
{
cout<<“welcome to C++”;
}
After you compile this program there is an error called prototype error. Why it is happened? Explain
Answer:
Here we used the output operator cout<<. It is used to display a message “welcome to C++” to use this operator the corresponding header file must be included. We didn’t included the header file hence the error. .

Question 6.
In C++ the size of the string “book” is 5 and that of “book\n” is 6. Check the validity of the above statement. Justify your answer.
Answer:
A string is automatically added by a null character). The null character is treated as one character. So the size of string “book” is 5. Similarly a null character (\0) is also added to “book\n”. \n and \0 is treated as single characters. Hence the size of the string “book\n” is 6.

Question 7.
Pick the odd man out. Justify
TOTSAL, TOT_SAL, totsal5, Tot5_sal, SALTOT, tot.sal,
Answer:
tot.sal. Because it contains a special character dot(,). An identifier cannot contain a special character. So it is not an identifier. The remaining satisfies the rules of naming identifier. So they are valid identifier.

Question 8.
Write a C++ statement to print the following sentence. Justify.
“\ is a special character”
Answer:
cout<<“\\ is a special character” \\ is treated as an escape sequence.

Question 9.
A student type a C++ program and saves it in his personal folder as Sample.cpp. After getting the output of the program, he checks the folder and finds three files namely Sample.cpp, Sample.obj and Sample.exe. Write the reasons for the generation of the two files in the folder.
Answer:
After the compilation of the program sample.cpp, the operating system creates two files if there is no error. The files are one object file (sample.obj) and one executable file(sample.exe). Now the source file(sample.cpp) and object file(sample.obj) are hot needed and can be deleted. To run the program sample.exe is only needed.

Question 10. Mention the purpose of tokens in C++. Write names of any four tokens in C++.
Answer:
Token : It is the smallest individual units similar to a word in English orMalayalam language. C++ has 5 tokens.
1) Keywords
2) Identifier
3) Literals (Constants)
4) Punctuators
5) Operators

Question 11. The following are some invalid identifiers. Specify its reason.
a) Sum of digits
b) 1 year
c) First jan
d) For
Answer:
a) Sum of digits —> space not allowed hence it is invalid
b) 1 year —> First character must be an alphabet hence it is invalid
c) First.jan —> special characters such as dot (.) not allowed hence it is invalid.
d) For —> It is valid. That is it is not the key word for

Question 12.
Some of the literals in C++ are given below. How do they differ? (5, ‘5’, 5.0, “5”)
Answer:
5 – integer literal
‘5’ – Character literal
5.0- floating point literal
“5”- string literal

Question 13.
Identify the invalid literals from the following and write reason for each:
a) 2E3.5
b) “9”
c) ‘hello’
d) 55450
Answer:
a) 2 C 3.5 – The mantissa part (3.5) will not be a floating point number. Hence it is invalid
c) ‘hello’ -> It is a string hence it must be enclosed in double quotes instead of single quotes. It is invalid.

Question 14.
Which one of the following is a user-defined name?
a) Key-word
b) Identifier
c) Escape sequences
d) All of these
Answer:
b) Identifier

Question 15.
Identify whether the following are valid identifiers or not? If not give the reason.
a) Break
b) Simple.interest
Answer:
a) Break – It is valid( break is the keyword, not Break);
b) Simple.interest – It is not valid, because dot(.) is used.

Question 16.
Identify the invalid literals from the following and write a reason for each:
a) 2E3.5
b) “9”
c) ‘hello’
d) 55450
Answer:
a) Invalid, because exponent part should not be a floating point number
b) valid

Plus One Computer Application Getting Started with C++ 3 Marks Questions and Answers

Question 1.
Rose wants to print as follows
\n is used for New Line
Write down the C++ statement for the same.
Answer:
#include
using namespace std;
int main( )
{
cout<<“\\n is used for New Line”;
}

Question 2.
Alvis wants to give some space using escape sequence as follows
Welcome to C++
Write down the C++ statement for the same .
Answer:
#include
using namespace std;
int main( )
{
cout<<“Welcome to \t C++”;
}

Question 3.
We know that the value of pi=3.14157, a constant (literal). What is a constant? Explain it?
Answer:
A constant or a literal is a data item its value doe 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,(5240, etc
For hexadecimal 0x100, 0x1A,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

Question 4.
Write a program to print the message “TOBACCO CAUSES CANCER” on screen,
Answer:
#include using namespace std; int main( )
{
cout<<” TOBACCO CAUSES CANCER”;
}

Question 5.
You are supplied with a list of tokens in C++ pro-gram, Classify and Categorise them under proper headings.
Explain each category with its features. tot_mark, age, M5,. …, break,( ), int, _pay, ; , cin
Answer:

Question 6.
Write a program to print the message “SMOKING IS INJURIOUS TO HEALTH” on screen. “SMOKING IS INJURIOUS TO HEALTH”
Answer:
#include
using namespace std;
int main( )
{
cout<<“SMOKING IS INJURIOUS TO HEALTH”;
}

Plus One Computer Application Getting Started with C++ 5 Marks Questions and Answers

Question 1.
Consider the following code
The new line character is \n.
The output of the following code does not contain the \n. Why it is happened? Explain.
Answer:
\n is a character constant and it is also known as escape sequence. This is used to represent the non graphic symbols such as carriage return key(enter key), tab key, back space, space bar etc. It consists of a back slash symbol and one more characters.

Question 2.
You are about to study the fundamentals of C++ programming Language. Do a comparative study of the basics of the new language with that of a formal language like English or Malayalam to familiarize C++?. Provide sufficient explanations for the compared items in C++ Language,
Answer:
Character set: To study a language first we have to familiarize the character set. For example to study English language first we have to study the alphabets. Similarly here the character set includes letters(A to Z & a to z), digits(0 to 9), special characters+,-,?,*,/, ) white spaces(non printable)
etc..
Token: It is the smallest individual units similar to a word in English or Malayalam language. C++ has 5 tokens
1) Keywords
Eg: float is used to declare variable to store numbers with decimal point. We can’t use this for any other purpose

2) identifier: These are user defined words. Eg: variable name, function name, class name, object name etc…

3) Literals (Constants): Its value does not change during execution
Eg: In maths π = 3.14157 and boiling point of water is 100.

4) Punctuators: In English or Malayalam language punctuation mark are used to increase the read-ability but here it is used to separate the tokens. Eg:{,},(,)……….

5) Operators: These are symbols used to perform an operation(Arithmetic, relational, logical, etc…)
These are reserved words for the compiler. We can’t use for any other purposes.

Students can Download Chapter 3 Principles of Programming and Problem Solving Questions and Answers, Plus One Computer Application Chapter Wise Questions and Answers helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Computer Application Chapter Wise Questions Chapter 3 Principles of Programming and Problem Solving

Plus One Computer Application Principles of Programming and Problem Solving 1 Mark Questions and Answers

Question 1.
The process of writing program is called _______.
Answer:
programming or coding.

Question 2.
One who writes program is called ______.
Answer:
Programmer.

Question 3.
The step by step procedure to solve a problem is known as ______.
Answer:
Algorithm.

Question 4.
Diagrammatic representation of an algorithm is known as ______.
Answer:
Flow .

Question 5.
Program errors are known as ______.
Answer:
bugs.

Question 6.
Process of detecting and correcting errors is called ________.
Answer:
debugging .

Question 7.
Mr. Ramu represents an algorithm by using some symbols. This representation is called ______.
Answer:
Flow Chart.

Question 8.
Your computer teacher asked you that which symbol is used to indicate beginning or ending flow chart? What is your answer?
a) Parallelogram
b) Rectangle
c) Oval
d) Rhombus
Answer:
c) Oval.

Question 9.
You are suffering from stomach ache. The doctor prescribes you for a scanning. This process is related in a phase in programming. Which phase is this ?
Answer:
Problem identification.

Question 10.
Your friend asked you a doubt that to draw a flow chart parallelogram is used for what purpose?
Answer:
input /output.

Question 11.
Mr. Anil wants to perform a multiplication which symbol is used to represent in a flow chart.
Answer:
It is a processing so rectangle is used.

Question 12.
Mr. George wants to check a number is greater than zero and to perform an operation while drawing a flow chart which symbol is used for this?
Answer:
Rhombus

Question 13.
ANSI means ______.
Answer:
American National Standards Institute.

Question 14.
To indicate the flow of an operation which symbol is used to draw a flow chart.
Answer:
Flow lines with arrow heads .

Question 15.
Mr. Johnson is drawing a flow chart but it is not fit in a single page. Which symbol will help him to complete the flow chart?
Answer:
Connectors.

Question 16.
Mr. Ravi developed a S/W student information system, He wants to protect the s/w from unauthorized copying. There is an act what is it?
Answer:
Copy right act.

Question 17.
Odd man out.
a) Parallelogram
b) Oval
c) Rectangle
d) Star
Answer:
d) Star, others are flowchart symbols.

Question 18.
Odd man out.
(a) Oval
(b) Rhombus
(c) Connector
(d) Triangle
Answer:
Triangle, Others are flowchart symbols.

Question 19.
Raju wrote a program and he wants to check the errors and correct if any? What process he has to do for this?
Answer:
process, debugging.

Question 20.
Odd one out.
a) Problem identification
b) Translation
c) debugging
d) copy right
Answer:
d) Copy right, others are phases in programming.

Question 21.
Odd man out.
a) syntax error
b) logical error
c) Runtime error
d) printer error
Answer:
d) Printer error, Others are different types of errors.

Question 22.
A computerized system is not complete after the execution and testing phase? What is the next phase to complete the system?
Answer:
Documentation.

Question 23.
Mr. Sathian takes a movie DVD from a CD library and he copies this into another DVD without per-mission. This process is called ______.
Answer:
Piracy.

Question 24.
Mr. Santhosh purchased a movie DVD and he takes several copies without permission. He is a _______.
a) Programmer
(b) Administrator
c) Pirate
(d) Organizer
Answer:
c) Pirate.

Question 25.
The symbol used for copy right is a _____.
a) &
(b) Copy
(c) #
(d) ©
Answer:
d)©

Question 26.
Following are the advantages of flowcharts one among them is wrong. Find it.
a) Better communication
b) Effective analysis
c) proper program documentation
d) Modification easy
Answer:
d) Modification easy, It is a disadvantage.

Question 27.
Which flow chart symbol has one entry flow and two exit flows?
Answer:
Diamond.

Question 28.
Which flow chart.symbol is always used in pair?
Answer:
connector.

Question 29.
Program written in HLL is called ______.
Answer:
Source code.

Question 30.
Some of the components in the phases of programming are given below. Write them in order of their occurrence.
a) Translation
b) Documentation
c) Problem identification
d)Coding of a program
Answer:
The chronological order is as follows
1) c) Problem Identification
2) d) Coding of a program
3) a) Translation
4) b) Documentation

Question 31.
a) ________ is the stage where programming errors are discovered and corrected.
Answer:
Debugging or compiling.

Question 32.
compilation and execution there were no errors. But he got a wrong output. Name the type of error he faced.
Answer:
Logical Error.

Question 33.
Pick out the software which rearranges the scattered files in the hard disk and improves the performance of the system.
a) Backup software
b) File compression software
c) Disk defragmenter 1
d) Anti virus software
Answer:
Disk defragmenter.

Question 34.
Some phases in programming are given below.
1) Source coding
2) Execution
3) Translation
4) Problem study
These phases should follow a proper order.
Choose the correct order from the following:
a) 4 —> 2 —> 3 —> 1
b) 1 —> 3 —> 2 —> 4
c) 1 —> 3 —> 4 —> 2
d) 4 —> 1 —> 3 —> 2
Answer:
d)4 —> 1 —> 3 —> 2

Question 35.
Which one of the following errors is identified at the time of compilation?
a) Syntax error
b) Logical error
c) Run-time error
d) All of these
Answer:
a) Syntax error.

Question 36.
Pick the odd one out and give a reason for your finding:

Answer:
c) This has one entry flow and more than one exit flow
OR
b) Used for both input and output..

Plus One Computer Application Principles of Programming and Problem Solving 2 Marks Questions and Answers

Question 1.
A debate on ‘Whether Free Software is to be promoted’ is planned in your class. You are asked to present points in support of Free Software. What would be your arguments, (at least three)?
Answer:
Freedom to use Comparatively cheap Freedom to modify and redistribute.

Question 2.
Mr. Roy purchased a DVD of a movie and he found that on the cover there is a sentence copy right reserved and a mark ©. What is it? Briefly explain?
Answer:
It is under the act of copy right and the trade mark is © copy right is the property right that arises automatically when a person creates a new work by his own and by Law it prevents the others from the unauthorized or intentional copying of this without the permission of the creator.

Question 3.
Can a person who knows only Malayalam talk to a person who knows only Sanskrit normally consider the corresponding situation in a computer program and justify your answer?
Answer:
Normally it is very difficult to communicate. But it is possible with the help of a translator. Translation is the process of converting programs written in High Level Language into Low Level Language (machine Language). The compiler or interpreter is used for this purpose. It is a program.

Question 4.
Define the term, debugging. Write the names of two phases that are included in debugging.
OR
Define the different types of errors that are encountered during the compilation and running of a program
Answer:
Debugging :- The program errors are called ‘bugs’ and the process of detecting and correcting errors is called debugging.
Compilation and running are the two phases.
OR
In general there are two types of errors syntax errors and logical errors. When the rules or syntax of the language are not followed then- syntax errors occurred and it is displayed after compilation. When the logic of a program is wrong then logical errors occurred and it is not displayed after compilation but it is displayed in the execution and testing phase.

Question 5.
Write an algorithm to input the scores obtained in three unit tests and find the average score.
OR

Explain the flow chart and predict the output.
Answer:
Step 1 : Start
Step 2 : Read S1, S2, S3
Step 3 : avg = S1 + S2 + S3/3
Step 4 : Print avg
Step 5 : Stop.
OR
This flowchart is used to print the numbers as 1,2,3, ……… 30

Question 6.
Differentiate between top down design and bottom up design in problem solving
Answer:
Bottom up design : Here also larger programs are divided into smaller ones and the smaller ones are again subdivided until the lowest level of detail has been reached. We start solving from the lowest module onwards. This approach is called Bottom up design.

Question 7.
Answer any one question from 5 (a) and 5 (b).
Draw a flowchart for the following algorithm.
Step 1 : Start
Step 2 : Input N
Step 3 : S=0, K=1
Step 4 : S = S +K
Step 5 : K = K +1
Step 6 : If K < = N Then Go to Step 4
Step 7 : Print s
Step 8 : Stop
OR
Name the two stages in programming where debugging process is involved. What kinds of errors are removed in each of these stages?
Answer:
a)

b) The two stages are compile time and run time. In the debugging process can remove syntax . error, logical error and runtime error.

Question 8.
Answer any one question from 7(a) and 7(b) .
a) Observe the following portion of a flowchart. Fill in the blank symbols with proper instructions to get 321 as the output.

b) The following flowchart can be used to print the numbers from 1 to 100. Identify another problem that can be solved using this flowchart and write the required instructions in the symbols.

Answer:
The following flowchart can be used to store another problem such as used to print odd numbers less than 200.
a)

b) The following flowchart can be used to store another problem such as used to print odd numbers less than 200.

Question 9.
Write an alogorithm to print the numbers upto 100 in reverse order, That is the output should be as 100, 99, 98, 97,… .1
OR
Draw a flow chart to check whether the given number is positive, negative or zero.
Answer:
Step 1 : Start
Step 2 : Set i < — 100
Step 3 : if i<=0 then go to step 6
Step 4 : Print i.
Step 5 : Set i < — i – 1 go to step 3
Step 6 : Stop

Plus One Computer Application Principles of Programming and Problem Solving 3 Marks Questions and Answers

Question 1.
When you try to execute a program, there are chances of errors at various stages, Mention the types of errors and explain.
Answer:
1) syntax error :
eg : 5=x
2) Logic error. If the programmer makes any logical mistakes, it is known as logical error.
Eg: To find the sum of values A and B and store it in a variable C you have to write C=A+B. Instead of this if you write C=A*B, it is called logic error.
3) Runtime error : An error occured at run time due to inappropriate data.
Eg: To calculate A/B a person gives zero to B. There is an error called division by zero error during run time.

Question 2.
Following is a flow chart to find and display the largest among three numbers. Some steps are missing in the flowchart. Redraw the flow chart by adding necessary.steps and specify its purpose. How can this flow chart be modified without using a fourth variable?
Answer:

Question 3.
A flow chart is given below.

a) What will be the output of the above flow chart ?
b) How can you modify the above flow chart to display the even numbers upto 20, starting from 2.
Answer:
a) 1,2,3,4,5.

Question 4.
Write an algorithm to check whether the given number is even or odd.
Answer:
step 1 : Start
Step 2 : Read a number to N
Step 3 : Divide the number by 2 and store the remainder in R.
Step 4 : If R = O Then go to Step 6
Step 5 : Print “N is odd” go to step 7
Step 6 : Print “N is even”
Step 7 : Stop

Question 5.
Write an algorithm to find the largest of 2 numbers?
Answer:
Step 1 : Start
Step 2 : Input the values of A, B
Step 3 : Compare A and B. If A> B then go to step 5
Step 4 : Print” B is largest” go to Step 6.
Step 5 : Print “A is largest”
Step 6 : Stop

Question 6.
Write an algorithm to find the sum of n natural numbers and average?
Answer:
Step 1 : Start
Step 2 : Set i 1, S 0
Step 3 : Read a number and set to n
Step 4 : Computer i and n if i>n then go to step 7.
Step 5 : Set S <— S+ i
Step 6 : i <— i+1 go to step 4
Step 7 : avg 4<— S/n Step 8 : Print “Sum = S and average = avg” Step 9 : Stop Question 7. Write an algorithm to find the largest of 3 numbers.
Answer:
step 1 : Start
Step 2 : Read 3 numbers and store in A,B,C
Step 3 : Compare A and B. lfA>B then go to Step 6
Step 4 : Compare B and C if C>B then go to Step 8
Step 5 : print “B is largest” go to Step 9
Step 6 : Compare A and C if Q>A then go to Step 8
Step 7 : Print” A is largest” go to Step 9
Step 8 : Print “C is largest”
Step 9 : Stop

Question 8.
Write an algorithm to calculate the simple interest (I =P*N*R/100)
Answer:
Step 1 : Start
Step 2 : Read 3 values for P,N,R
Step 3 : Calculate I <— P*N*R/100
Step 4 : Print “The simple interest = I
Step 5  : Stop

Question 9.
Write an algorithm to calculate the compound interest (C. I = Px(1 +r/100)n – P)
Answer:
Step 1 : Start
Step 2 : Read 3 number for p,n,r
Step 3 : Calculate Cl = p x(1+r/100)n – p
Step 4 : Print “The compound Interest = C.I”
Step 5 : Stop

Question 10.
Write an algorithm to find the cube of first n natural numbers .(eg:1,8,27 …….. n³)
Answer:
Step 1 : Start
Step 2 : Set i <— 1
Step 3 : Read a number and store in n
Step 4 : Compare rand n if i>n then go to step 7
Step 5 : Print i*i*i
Step 6 : i <— i+1 go to step 4
Step 7 : Stop

Question 11.
Write an algorithm to read a number and find its factorial (n!=n*(n-1)*(n-2) * …..3*2*1)
Answer:
Step 1 : Start
Step 2 : Fact <—1
Step 3 : Read a number and store in n
Step 4 : If n=0 then go to step 7
Step 5 : Fact <— Fact *n
Step 6 : n <— n-1 go to step 4
Step 7 : Print “Factorial is fact”
Step 8 : Stop.

Question 12.
Draw a flow chart to find the sum of n natural numbers and average.
Answer:

Question 13.
Draw a flow chart to find the largest of three numbers.
Answer:

Question 14.
Draw a flow chart to find the largest of two numbers.
Answer:

Question 15.
Draw a flow chart to check whether the given number is even or odd.
Answer:

Question 16.
Draw a flow chart to calculate the simple interest.
Answer:

Question 17.
Draw a flow chart to calculate compound interest.
Answer:

Question 18.
Draw a flow chart to find the cube of n natural numbers (1,8,27 …….n³)
Answer:

Question 19.
Draw a flow chart to read a number and find its factorial.
Answer:

Question 20.
Mr. Vimal wants to represent a problem by using a flowchart, which symbols are used for this. Explain.
Answer:



These symbols will help us to complete the flow chart, which is not fit in a single page. A connector symbol is represented by a circle and a letter or digit is placed within the circle to indicate the link.

Question 21.
Jeena uses algorithm to represent a problem while Neena uses flowchart which is better? Justify your answer?
Answer:
Flow chart is better. The advantages of flow chart is given below.
1. Better communication:- A flow chart is a pictorial representation while an algorithm is a step By step procedure to solve a program. A programmer can easily explain the program logic using a flow chart.
2. Effective analysis :- The program can be analyzed effectively through the flow chart.
3. Effective synthesis :- If a problem is big it can be divided into small modules and the solution for each module is represented in flow chart separately and can be joined together to get the final system design.
4. Proper program documentation :- A flow chart will help to create a document that will help the company in the absence of a programmer.
5. Efficient coding :- With the help of a flow chart it is easy to write program by using a computer language.

Question 22.
A flow chart is a better method to represent a program. But it has some limitation what are they?
Answer:
The limitations are given below
1) To draw a flowchart, it is time consuming and laborious work.
2) If any change or modification in the logic we . may have to redraw a new flow chart.
3) No standards to determine how much detail can include in a flow chart.

Question 23.
Match the following,

Answer:
1 – e
2 – a
3 – d
4 – f
5 – b
6 – c

Question 24.
Alvis executes an error – free program but he got an error. Explain different types of error in detail.
Answer:
There are two types of errors in a program before execution and testing phase.They are syntax error and logical error. When the programmer violates the rules or syntax of the programming language then the syntax error occurred.
Eg: It involves incorrect punctuation. Key words are used for other purposes, violates the structure etc. It detects the compiler and displays an error message that include the line number and give a clue of the nature of the error. When the programmer makes any mistakes in the logic, that types of errors are called logical error. It does not detect by the compiler but we will get a wrong output.
The program must be tested to check whether it is error free or not. The program must be tested by giving input test data and check whether it is right or wring with the known results. The third type of errors are Runtime errors, this may be due to the in appropriate data while execution. For example consider B/C. If the end user gives a value zero for c, the execution will be interrupted because division by zero is not possible. These situation must be anticipated and must be handled.

Question 25.
The following are the phases in programming. The order is wrong rearrange them in correct order.
1. Debugging
2. Coding
3. Derive the steps to obtain the solution
4. Documentation
5. Translation
6. Problem identification
7. Execution and testing
Answer:
The correct order is given below.
1. Problem identification
2. Derive the steps to obtain the solution
3. Coding
4. Translation
5. Debugging
6. Execution and testing
7. Documentation

Question 26.
Draw a flow chart to input ten different numbers and find their average. ‘
Answer:

Question 27.
Draw the flow chart to find the sum of first N natural numbers.
Answer:

Question 28.
Make a flow chart using the given labelled symbols, for finding the sum of all even numbers upto ‘N’

Answer:
Draw flowchart in any of the following order
e, c, d, f, i, h, a, b, g
e, d,c, f, i, h, a, b, g
e, c, d, a, f, i, h, b, g
e, d, c, a, f, i, h, b, g
Step 1 : Start
Step 2 : Input n
Step 3 : i = I
Step 4 : if i<=n/2 then repeat step 5 & 6
Step 5 : if n%i = = 0 print i
Step 6 : i = i + I
Step 7 : Stop

Question 29.
List the two approaches followed in problem solving or programming. How do they differ?
Answer:
Approaches in problem solving Top down design : Larger programs are divided into smaller ones and solve each tasks by performing simpler activities. This concept is known as top down design in problem solving Bottom up design : Here also larger programs are divided into smaller ones and the smaller ones are again subdivided until the lowest level of detail has been reached: We start solving from the lowest module onwards. This approach is called Bottom up design. Phases in Programming

1) Problem identification : This is the first phase in programming. The problem must be identified then only it- can be solved, for this we may have to answer some questions. During this phase we have to identify the data, its type, quantity and formula to be used as well as what activities are involved to get the desired out put is also identified for example if you are suffering from stomach ache and consult a Doctor. To diagnose the disease the Doctor may ask you some question regarding the diet, duration of pain, previous occurrences etc, and examine some parts of your body by using stethoscope X-ray, scanning etc.

2) Deriving the steps to obtain the solution: There are two methods, Algorithm and flowchart, are used for this.
a) Algorithm :- The step-by-step procedure to solve a problem is known as algorithm. It comes from the name of a famous Arab mathematician Abu Jafer Mohammed Ibn Musaa Ai-Khowarizmi, The last part of his name Al-Khowarizmi was corrected to algorithm.
b) Flowchart :- The pictorial or graphical representation of an algorithm is called flowchart.

Question 30.
Write an algorithm to find the sum of the squares of the digits of a number. (For example, if 235 is the input, the output should be 22+32+52=38)
Answer:
Step 1 : Start
Step 2 : Set S = O
Step 3 : Read N
Step 4 : if N > O repeat step 5, 6 and 7
Step 5 : Find the remainder. That is rem =N%10
Step 6 : S = S + rem * rem
Step 7 : N = N/10
Step 8 : Print S
Step 9 : Stop

Question 31.
Consider the following algorithm and answer the following questions:
Step 1 : Start
Step 2 : N=2, S=0
Step 3 : Repeat Step 4, Step 5 while N<=10
Step 4 : S=S+N
Step 5 : N=N+2
Step 6 : Print S
Step 7 : Stop
a) Predict the output of the above algorithm.
b) Draw a flowchart for the above algorithm
Answer:
a) The output is 30

Question 32.
“It is better to give proper documentation within the program”. Give a reason.
Answer:
It is the last phase in programming. A computerized system must be documented properly and it is an ongoing process that starts, in the first phase and continues till its implementation. It is helpful for the modification of the program later.

Plus One Computer Application Principles of Programming and Problem Solving 5 Marks Questions and Answers

Question 1.
Mr. Arun wants to develop a program to computerize the functions of super market. Explain different phases he has to under go is detail.
OR
Briefly explain different phases in programming.
Answer:
The different phases in programming is given below:
1) Problem identification : This is the first phase in programming. The problem must be identified then only it can be solved, for this we may have to answer some questions.
During this phase we have to identify the data, its type, quantity and formula to be used as well as what activities are involved to get the desired out put is also identified for example if you are suffering from stomach ache and consult a Doctor. To diagnose the disease the Doctor may ask you some question regarding the diet, duration of pain, previous occurrences etc, and examine some parts of your body by using stethoscope X-ray, scanning etc.

2) Deriving the steps to obtain the solution. There are two methods, Algorithm and flowchart, are used for this.
a) Algorithm :- The step-by-step procedure to solve a problem is known as algorithm. It comes from the name of a famous Arab mathematician Abu Jafer Mohammed Ibu Musaa Al-Khowarizmi, The last part of his name Al-Khowarizmi was corrected to algorithm.
b) Flowchart:- The pictorial or graphical representation of an algorithm is called flow-chart.

3) Coding The dummy codes (algorithm)or flow-chart is converted into program by using a computer language such s Cobol, Pascal, C++, VB, Java etc.

4) Translation The computer only knows ma-chine language. It does not know HLL, but the human beings HLL is very easy to write pro. grams. Therefore a translation is needed to convert a program written in HLL into machine code. (object code). During this step, the syntax errors of the program will be displayed. These errors are to be corrected and this process will be continued till we get “No errors” message. Then
it is ready for execution.

5) Debugging The program errors are called ‘bugs’ and the process of detecting and correcting errors is called debugging. In general there are two types of errors syntax errors and logical errors. When the Riles or syntax of the language are not followed then syntax errors occurred and it is displayed after compilation. When the logic of a program is wrong then logical errors occurred and it is not displayed after compilation but it is displayed in the execution and testing phase.

6) Execution and Testing In this phase the program will be executed and give test data for testing the purpose of this is to determine whether the result produced by the program is correct or not. There is a chance of another type of error, Run time error, this may be due to in-appropriate data.

7) Documentation It is the last phase in programming. A computerized system must be documented properly and it is an ongoing process that starts in the first phase and continues till its implementation. It is helpful for the modification of the program later.

Question 2.
Briefly explain the characteristic of an algorithm.
Answer:
The following are the characteristics of an algorithm
1) It must starts with ‘start’ statement and ends with ‘stop’ statement.
2) it should contains instructions to accept input and these are processed by the subsequent instructions.
3) Each and every instruction should be precise and must be clear. The instructions must be possible to carry out, for example consider the examples the instruction “Go to market” is precise and possible to carried out but the instruction “Go to hell” is also precise and can not be carried out.
4) Each instruction must be carried out in finite time by a person with paper and pencil.
5) The number of repetition of instructions must be finite.
6) The desired results must be obtained after the algorithm ends.

Students can Download Chapter 2 Components of the Computer System Questions and Answers, Plus One Computer Application Chapter Wise Questions and Answers helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Computer Application Chapter Wise Questions Chapter 2 Components of the Computer System

Plus One Computer Application Components of the Computer System 1 Mark Questions and Answers

Question 1.
The Tangible parts of a computer is ______.
Answer:
Hardware

Question 2.
The instructions that tell the hardware to perform a task is ______.
Answer:
Software

Question 3.
The brain of the computer is ______.
Answer:
CPU

Question 4.
CPU means _____.
Answer:
Central Processing Unit

Question 5.
ALU is ______.
Answer:
Arithmetic Logic Unit

Question 6.
I am an input device. I can read text or picture on paper and translate into computer usable form. Who am i?
Answer:
Scanner

Question 7.
Odd man out.
Answer:
a) Track ball
b) Joy Stick
c) Scanner
d) LCD
LCD. It is an output device. Others are input device

Question 8.
Odd man out.
a) Inkjet
b) Laser
c) Dot Matrix Printer
d) Thermal
Answer:
Dot Matrix Printer.
It is impact printer others are non impact printers.

Question 9.
The storage capacity of a CD is ______
(a) 1.44 MB
(b) 700 GB
(c) 700 MB
(d) 650 GB IIP
Answer:
700 MB

Question 10.
_______ sheet is used to write answers in Kerala Entrance Exam.
Answer:
OMR Sheet

Question 11.
ABC textile uses ____ reader to input the item and its price.
Answer:
Bar code reader.

Question 12.
________ device senses the presence or absence of a pencil mark.
Answer:
OMR

Question 13.
Name any two printing devices.
Answer:
Mouse and touchpad.

Question 14.
______ is a device that draws pictures on a paper.
Answer:
Plotter.

Question 15.
Primary memory is classified into two What are they?
Answer:
RAM and ROM.

Question 16.
The storage capacity of a DVD is ______.
Answer:
4.7 GB.

Question 17.
Winzip is a ______ utility
Answer:
Compression utility.

Question 18.
Win Rar is a ______ utility
Answer:
Compression utility.

Question 19.
Most commonly used input device is ______.
Answer:
Keyboard or mouse.

Question 20.
Govt decided to conduct a test that contains all objective type questions. Which device is most suitable for evaluation.
Answer:
OMR

Question 21.
______ is used mostly for computer games.
Answer:
Joy stick.

Question 22.
I am an input device. I have a stick with two but-tons called triggers on the top. Who am I?
Answer:
Joy stick.

Question 23.
I am a pointing device. I am a stationary device. Who am I?
Answer:
Touchpad.

Question 24.
In portable computers which pointing device is suitable?
Answer:
Touchpad.

Question 25.
State true or false.
Hard copy devices are very slow compared to soft copy devices.
Answer:
True.

Question 26.
_______ is also called firm ware.
Answer:
ROM.

Question 27.
_______ is acts as an interface between user and computer.
Answer:
Operating system.

Question 28.
is used to create and modify any type of document.
Answer:
Word Processor.

Question 29.
_____ is a set of programs that manage the data base.
Answer:
DBMS.

Question 30.
package contains rows & columns.
Answer:
Spread sheet.

Question 31.
_____ is a presentation package.
Answer:
Power Point.

Question 32.
Your computer teacher asked you to explain the project work done by your group. Which package will help you to do so?
Answer:
Power Point.

Question 33.
_____ is a DTP Package.
(a) Excel
(b) PowerPoint
(c) PageMaker
(d) None of these
Answer:
PageMaker.

Question 34.
DTP is _______.
Answer:
Desk Top Publishing.

Question 35.
______ is designed to help computer for its smooth functioning.
Answer:
Utilities

Question 36.
Customised software is also called ________.
Answer:
Tailor made software.

Question 37.
_______ S/W is used to remove virus from a computer.
Answer:
Anti Virus S/W

Question 38.
Name any anti virus S/W.
Answer:
Norton Anti virus,.McAfee, Avira, AVG

Question 39.
Name the two classifications of output devices.
Answer:
Hard copy and soft copy.

Question 40
Name, the two classification of printers.
Answer:
Impact printer and non-impact printer.

Question 41.
________ gas is used in plasma panels
(a) Oxygen
(b) Neon
(c) Mercury
(d) helium
Answer:
Neon

Question 42.
_______ printers are used in fax machine.
Answer:
Thermal Printers

Question 43.
________ is read / write memory.
Answer:
RAM

Question 44.
______ is of volatile memory
(a) ROM
(b) RAM
(c) CD
(d) DVD
Answer:
RAM

Question 45.
From the following which is expensive?
(a) CD
(b) DVD
(c) HDD
(d) RAM
Answer:
RAM

Question 46.
You want to input your photograph into computer. Which device is used for this?
(a) Scanner
(b) Mouse
(c) OMR
(d) OCR
Answer:
Scanner

Question 47.
The primary memory which is commonly used in electronic billing machines to store price of products is
a) PROM
b) E P R O M
c)E EPROM
d) None of these
Answer:
EPROM

Question 48.
Name any three pointing devices.
Answer:
Mouse, Touchpad and light pen.

Question 49.
You want to print your brother’s resume which printer will you choose. Why ?
Answer:
I will choose either Ink-jet or Laser printer. Because these produce less noise and produce high quality printing output. They are used to print characters as well as graphics (Photos) with very high quality.

Question 50.
The fastest memory in a computer is
Answer:
Registers

Question 51.
The storage capacity of a single layer DVD is ______.
Answer:
4.7 GB

Question 52.
Give two examples for OS.
Answer:
Windows 7, Windows Vista.

Question 53.
A program in execution is called ______.
Answer:
Process.

Question 54.
Name the software that translates assembly language
Answer:
assembler.

Question 55.
DBMS stands for _____.
Answer:
Data Base Management System.

Question 56.
Duplicating disc information is called ______.
Answer:
Backup.

Question 57.
An example of free and open source software is _______.
Answer:
Linux.

Question 58.
The software that gives users a chance to try it before buying is ______.
Answer:
Shareware.

Question 59.
An example of proprietary software is ______.
Answer:
Tally.

Question 60.
Which software is used for calculation?
a) Word processor
b) Spreadsheet
c) Presentation
d) Multimedia
Answer:
b) Spread sheet.

Question 61.
Accumulator stores
a) address of data
b) instruction to be executed
c) address of next instruction to be executed
d) intermediate result
Answer:
d) intermediate result.

Question 62.
If Tracks and Sectors: Hard disk, then _______ Compact disk
Answer:
Pits and Lands (OR) 0 and 1

Question 63.
Which one of the following file extensions is different from others? ,
a) WAV
b) MP3
C) PNG
d) MIDI
Answer:
PNG, the others are audio files.

Question 64.
Which register holds the memory address of next instruction to the executed?
a) Accumulator
b) PC
c) MBR
d) MAR
Answer:
PC

Question 65.
a) Write the following memory devices in the order of their speed, (fastest to slowest order)
i) Cache
ii) RAM
iii) Hard Disk
iv) Registers
b) What do you mean by Freeware and Shareware?
Answer:
a) i) Registers
ii) Cache
iii) RAM
iv) Hard Disk
b) Freeware : A s/w with Copy right is available free of cost for unlimited use.
Shareware : It is an introductory pack distributed on a trial basis with limited functionality and period.

Plus One Computer Application Components of the Computer System 2 Marks Questions and Answers

Question 1.
The Higher Secondary Department wishes to conduct an examination for +1 students with multiple choice questions and publish results as soon as possible. Suggest a method to evaluate the answer scripts and publish the results quickily & correctly with the help of computers.
Answer:
OMR has to be used, it senses the presence or absence of a mark (bubbles) using a high density beam then converted into electric signals for computer. It needs good quality expensive paper and accurate alignment of printing on forms.

Question 2.
Remesh is a graphic designer who prepares his drawing using a computer. He desires for an alternative device by which he can draw directly on the screen. Suggest a device for this and explain it working.
Answer:
Light pens are used for this. It consists for a photocell placed in a small tube, it is able to detect the light coming from the screen. Hence locate the exact position on the screen. It is used by graphic designers, illustrators and drafting engineers, with the help of.CAD to draw directly on the screen.

Question 3.
You might have noticed that in some shops billing is done using computers without typing the item name, price, quantity, etc. Mention the device used for entering data and explain its working.
Answer:
A device called Bar Code Reader is used for this. It contains photoelectric scanner that read the bar code and input the information to the computer attached to it. It helps to reduce the errors and process the bills quickly.

Question 4.
Your school has arranged an excursion. You are having an ordinary camera whereas your friend has a digital camera. List the benefits your friend enjoys by using digital camera.
Answer:
1) Digital camera does not need film.
2) More number of shots can take
3) Operational cost is less
4) Very easy to manipulate images in digital form using computers.

Question 5.
A medical shop in your locality wishes to purchase a printer for their billing purpose. Which type of printer will you recommend if carbon copies are to be taken. Justify.
Answer:
Dot Matrix Printer.
To take carbon copies impact printer is a must, operational cost is less and it can print bills in a moderate speed.

Question 6.
Find the exact match.

Answer:
1-D
2-C
3-B
4-A

Question 7.
Your friend wishes to start § DTP centre with facilities to design posters and notices, to scan pictures and modify them and to print them. What would be your suggestions regarding the computer and peripherals?
Answer:
The requirements are computer, scanner, printer and software.

Question 8.
Find the most appropriate match.

Answer:
a) 1-D
b) 2-C
c) 3-A
d) 4 – B

Question 9.
Suggest a suitable device for the following.
a) High quality printing
b) High quality drawing
c) Printing with carbon copies
c) Economical printing of small quantities of data
d) data economically
Answer:
a) Non impact – Laser printers, Inkjet
b) Plotter
c) Impact (DMP(Dot Matrix Printer))
d) Dot Matrix Printers

Question 10.
“Not all primary memory is volatile”. Justify this statement.
Answer:
Primary Memory (Main memory) is classified into two RAM and ROM. Out of this RAM is volatile but ROM is non volatile.

Question 11.
Categorise the softwares in the list according to the appropriate classifications given below.’
Answer:
Classification : OS, Compiler, DTP Software, Com-pression software, Word processor
List : Open Office Writer, Photoshop, 7 Zip, MS Word, Unix, C++, PageMaker, Winzip, C, Windows 98,
OS – Unix, Windows 98
Compiler – C, C++
DTP Software – Photoshop, PageMaker
Compression – 7 Zip, Winzip ;
Word Processor – Open Office Writer, MS word

Question 12.
Your friend has just assembled a computer. Now he is provided with installation CD’s of MS Word and Microsoft Windows XP. In what order will he install them? Justify your answer.
Answer:
First he has to install the Microsoft Windows XP because it is the OS, it makes the computer to work other programmes. After that only he can install . MS Word it is a package.

Question 13.
A group of 20 students is given a test in 6 subjects. The examiner wishes to prepare a neatly formatted marklist with total and Rank. Suggest a suitable software to serve this purpose. Give reasons.
Answer:
The spread sheet Excel is a suitable software to serve this purpose. It consists of inbuilt functions, that facilitates to find total and rank easily

Question 14.
A program is written in BASIC, C and assembly language. Mention the difference in converting these programs to machine language.
Answer:
a) C – Compiler
b) BASIC – Interpreter
c) Assembly Language – Assembler

Question 15.
Your friend told you that he has a system. What is a system ? Explain..
Answer:
A computer is also called a system. A computer is not a single unit. It consists of more than one unit such as input unit, output unit, memory unit, ALU and control unit. Therefore a computer is called a system.

Question 16.
What is cache memory?
Answer:
A cache (pronounced cash) memory is a high speed memory placed in between the processor and pri-mary memory to reduce the speed mismatch be-tween these two.

Question 17.
What is the use of program counter register?
Answer:
This register stores the memory address of the next instruction to be executed by the CPU.

Question 18.
What is HDMI?
Answer:
Its full form is High Definition Multimedia Interface. Through this port we can connect high definition quality video and multi channel audio over a single cable.

Question 19.
Give two examples for customized software.
Answer:
1) Pay roll System : It keeps track of details of employee and their salary details-in an organisation
2) Inventory Management System : It keeps tack of all about inventory in a company

Question 20.
What do you mean by free and open source s/w?
Answer:
Here “free” means there is no copy right or licensing. That is we can take copies of the s/w or modify the source code without legal permission of its vendor (creator) we can use and distribute its copy to our friends without permission. That is Freedom to use, to modify and redistribute.

Question 21.
a) What do you mean by cache memory?
b) Write the names of the figures given below.
Answer:
a) It is a high speed memory placed in between . the CPU and RAM. CPU is a high speed memory compared to RAM. There is a speed mismatch between the CPU and RAM to resolve this problem a high speed memory called cache memory is placed in between the CPU and RAM
b) QR code and Bar Code such as input unit, output unit, memory unit, ALU and control unit. Therefore a computer is called a system.

Question 22.
What is the role of students in e-Waste disposal?
Answer:
Students’ role in e-Waste disposal

1. Stop buying unnecessary electronic equipments
2. Repair Faulty electronic equipments instead of buying a new one.
3. Give electronic equipments to recycle
4. Buy durable, efficient, quality, tbxic free, good warranty products
5. check the website or call the dealer if there is any exchange scheme
6. Buy rechargeable battery products

Plus One Computer Application Components of the Computer System 3 Marks Questions and Answers

Question 1.
Why is the paper coming from the laser printer hot? Explain.
Answer:
Laser printer uses photocopying technology. It uses a positively charged drum and negatively charged toner (dry powder). A laser beam is used to scan the page to be printed on the drum with positive charge and then rolled through a reservoir of negatively charged toner. It uses a combination of heat and pressure to adhere the dry powder to the paper. That is why, the paper coming from the laser printer is hot.

Question 2.
Explain the process how data from the hard disk is taken to the processor for processing.
Answer:
A processor is a high speed device. It can access data only from the Primary Memory (RAM). So we have to transfer data from hard disk to RAM. We know that a hard disk is a slow device also. So data is first transferred to RAM. A RAM is comparatively slower than processor. To reduce the speed mis-match between the RAM and processor, the data has to transfer to CPU registers. Then the processor takes the data from the CPU register because CPU register has almost equal speed as processor.

Question 3.
Why computer is called as a system?
Answer:
A computer is also called a system. A computer is not a single unit. It consists of more than one unit such as input unit, output unit, memory unit, ALU and control unit. Therefore a computer is called a system.

Question 4.
Differentiate hardware and software.
Answer:
The tangible parts of a computer is called hardware. We can see, touch and feel the hardware in a computer.’
The set of instructions that tell the hardware how to perform a task is called software. Without software computer cannot do anything

Question 5.
We all have a brain. Just like this, is the computer has a brain? Explain it?
Answer:
Yes. CPU is the brain of a computer. The CPU comprises three parts ALU, Control Unit and Memory. The control unit control the overall functioning of a system. ALU performs all the arithmetic calculations and takes logical decisions. Memory is used for storage of data for future reference.

Question 6.
Explain the various functions of a control unit.
Answer:
The control unit performs the following functions.
1) It controls data flow between input device. ALU, memory and output devices.
2) Normal execution of a program is line by line. The control unit controls this sequence with the help of ALU and memory.
3) It controls the decoding and interpretation of instructions.

Question 7.
Match the following

Answer:
1-c
2-d
3-f
4-a
5-b
6-e

Question 8.
Write down the full form of the following.
a) VDU
b) OMR
Answer:
a) VDU – Visual, Display Unit
b) OMR – Optical Mark Reader.

Question 9.
We know that a scanner is a hardware. What do you think of a virus scanner ? Explain.
Answer:
We know that a scanner is a hardware but a virus scanner is not a hardware. It is a program. That is a virus scanner is an antivirus software. That scans your disk (HDD, CD, DVD, Pen Drive ) for viruses and removes .them (if it can), if any virus is found.

Question 10.
Your friend told you that a compiler is a hardware. Is it true ? Justify your answer.
Answer:
It- is not true. A compiler is not a hardware but it is a software. A compiler is a collection of programs that translates program written in HLL into machine language

Question 11.
Anil purchased a product from a super market and he found that its wrapper contains light and dark bars. What is the purpose of this ?
Answer:
This light and dark bars are called bar code. It is used to record some details about the product such as item code, name, price etc…. A device called Bar Code Reader contains photo electric scanner that read the bar code and input the information to the computer attached to it. It helps to reduce error arid process the bills quickly.

Question 12.
What are the disadvantages of OMR ?
Answer:
The disadvantages are:
1) It heeds accurate alignment of printing on forms.
2) It needs good quality expensive paper.

Question 13.
Differentiate CRT and LCD (OR) Your friend going to purchase a computer. He asked you which is better, CRT or LCD ? What is your opinion ?
Answer:
The difference between CRT and LCD is given below:

So LCD is more better than CRT

Question 14.
While you pressing “A” on the keyboard what is actually stored in the memory ?
Answer:
The keyboard is an electro mechanical device that is designed to Greate electronic codes when a key is pressed and this code is transmitted to the memory through the cable. Here while you pressing “A” on the keyboard, the electronic codes corresponding to the ASCII value 01000001 is transmitting to the memory.

Question 15.
Your family friend started a super market. He asked you, which printer is suitable to print bills. Give your suggestion.
Answer:
According to my opinion, dot matrix printer is most suitable. Because they are capable of faster printing as well as it is cheap also. It’s printing quality is not good but cost per copy is very cheap. Dot matrix printer consists of a ribbon catridge that is cheap and can be changed easily. Here we have to print more copies at a time. So dot matrix is suitable.

Question 16.
Suppose your brother is an engineer. He wants to draw some drawings. Which output device is suitable? Explain.
Answer:
Plotter is suitable for him. A plotter is a device that draws pictures or diagrams on paper based on commands from a computer. Plotters draw lines using a pen. Pen plotters generally use drum or flat bed paper holders. In a drum plotter the paper is mounted on the surface of a drum. Here the paper is rotated. But in a flat bed plotter the paper does not move and the pen holding mechanism provides the motion that draws pictures. Plotters are used in engineering applications where precision is needed.

Question 17.
Match the following.

Answer:
1-b
2-a
3-d
4-e
5-c

Question 18.
There are special purpose storage locations within  the CPU. What are they explain ?
Answer:
Registers are special purpose storage locations within the CPU. They are temporary storage locations. The processing power of a CPU depends on register. Registers appears with storage capacity of 8 bits, 16 bits, 32 bits an 64 bits. They accept, store and transfer data from the CPU at a very high speed.
Program Counter : This register stores the memory address of the next instruction to be executed by the CPU.
Instruction Register : The instruction to be executed is stored in this register.
Memory Address Register : The address on the memory location from which data has to be read is stored here.
Memory Buffer Register : The data read from the location specified by the MAR is stored in this register.
General Purpose Registers : These are used to store the result and interrpediate results during a processing.

Question 19.
What is an operating system? flag operating system
Answer:
An operating system acts as an interface between user and computer without an operating system computer is a bare machine. That is without an OS computer cannot do anything. The OS not only makes the system convenient to use but also use hardware in an efficient manner,
eg:- Windows XP, Vista, Linux* MS Dos, Windows 7.

Question 20.
We know that a computer only knows low level Ianguage and human beings use high level language.
So how is it possible to communicate? Explain.
Answer:
The language processors translate the programs written in HLL into machine language which is understood by the computer, The different language processors are given below:
i) Assembler : This language processor translates programs written in assembly language into ma-chine language.
ii) Interpreter : This language processor translates < programs written in HLL into machine language by converting and executing it line by line. If there is any error, the execution is stopped we can continue after the correction of the program.
iii) Compiler : This language processor is same as interpreter. But it translates HLL into machine language by converting whole lines at a time. If there is any error, correcting all the errors then only it will execute.

Question 21.
Normally a CD contains 700 MB. Is it possible to store a file with size 1 GB? Explain.
OR
Normally a Car has a seating capacity of 5 persons including the driver. But some adjustments more persons can be accommodated in Car. This is connected with a utility. Which is the utility? Explain.
Answer:
Compression utility is used for this. By using compression utility programs we can reduce the file size upto the one third of the file size. So by using this we can reduce 1GB file and store in a CD. It is provided by the OS. The other compression utility programs are Winzip, WinRar etc. It is possible to compress the files and when needed, these com-pressed files can be uncompressed and it is restored to their original form.

Question 22.
What is a Virus?
Answer:
A virus is a bad program or harmful program to damage routine working of a computer system. It reduces the speed of a computer. It may be delete the useful system files and make the computer useless.

Question 23.
What do you mean by Utilities?
Answer:
Utilities are useful programs which are designed to help computer for its smooth functioning. Some utilities are back up utility, Disk defragmentation. Virus scanner, etc. It is provided by the O.S.

Question 24.
Differentiate RAM and ROM.
Answer:
The difference between RAM and ROM is given below.

Question 25.
Mention any two functions of OS.
Answer:
Major functions of an operating System
i) Process management: It includes allocation and de allocation of processes(program in execution) as well as scheduling system resources in efficient manner
ii) Memory management: It takes care of allocation and de allocation of memory in efficient manner
iii) File management : This includes organizing, naming , storing, retrieving, sharing , protecting and recovery of files.
iv) Device management : Many devices are connected to a computer so it must be handled efficiently.

Question 26.
Give two examples of human ware.
Answer:
(Write any two from the following)
The term refers the persons who use computer System Administrator: It is a person who has central control over the computer systems.
System Managers: He is responsible for all business transactions with all vendors and contractors.
System Analysts: He is responsible to improve the productivity and efficiency.
Database Administrator – It is a person who has a central control over the DBMS.
Computer Engineer: The person design either h/w or s/w of a computer system.
Application Programmer- These are computer professionals who interact with the DBMS through programs.
Computer operators : He is an end user and does not know computer in detail.

Question 27.
Explain how e-waste creates environmental and health problems. What are the different methods for e-waste disposal? Which one is the most effective in your point of view? Why?
Answer:
e-Waste(electronic waste) : It refers to the mal functioning electronic products such as faulty computers, mobile phones, tv sets, toys, CFL, batteries etc.
It contains poisonous substances such as lead, mercury, cadmium etc and may cause diseases if not properly managed.
A small amount is recycled. Due to this our natural resources are contaminated(poisoned). Some of them can recycle properly. But it is a very big problem in front of the Government to collect segregate, recycle and disposal of e-Waste.

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 b thick layer of soil.

Question 28.
What do you mean by e-waste? Explain the role of students in e-waste disposal.
Answer:
e-Waste(electronic waste) : It refers to the mal functioning electronic products such as faulty computers, mobile phones, tv sets, toys, CFL etc. It contains poisonous substances such as lead, mercury, cadmium etc and may cause diseases if not properly managed.

Students’ role in e-Waste disposal

1. Stop buying unnecessary electronic equipments
2. Repair Faulty electronic equipments instead of buying a new one.
3. Give electronic equipments to recycle
4. Buy durable, efficient, quality, toxic free, good warranty products
5. check the website or call the dealer if there is any exchange scheme
6. Buy rechargeable battery products

Plus One Computer Application Components of the Computer System 5 Marks Questions and Answers

Question 1.
Write short notes about input devices.
Answer:
An input device is used to supply data to the computer. They are given below:
1) Key board : It is the most widely used device to input information in the form of words, numbers etc. There are 101 keys on a standard key board. The keys on the key board are often classified into alpha numeric keys (A to Z, 0 to 9), function keys (F1 to F12), special purpose keys (Special characters), cursor movement keys (arrow keys). While pressing a key, the corresponding code’s signal is transmitted to the computer.

2) Mouse : It is a pointing device, that controls the movement of the cursor, or pointer as a display screen. A mouse has two or three buttons, it is often used in GUI oriented computers. Under the mouse there is a ball, when the mouse moves on a flat surface this ball also moves. This mechanical motion is converted into digital values that represents x and y values of the mouse movement.

3) Optical Mark Reader (OMR): This device identifies the presence or absence of a pen or pen-cil mark. It is used to evaluate objective {ype exams. In this method special preprinted forms are designed with circles can be marked with dark pencil or ink. A high intensity beam in the OMR converts this into computer usable form and detects the number and location of the pencil marks. By using this we can evaluate easily and reduce the errors.

4) Bar code / Quick Response (QR) code reader: Light and dark bars are used to record item name, code and price is called Bar Code. This information can be read and input into a com-puter quickly without errors using Bar Code Readers. It consists of a photo electric scanner and it is used in super market, jewellery, textiles etc.
QR codes are similar to barcodes but it uses two dimensional instead of single dimensional used in Barcode.

5) Joy Stick: It is a device that lets the user move an object quickly on the screen. It has a liver that moves in all directions and controls the pointer or object. It is used for computer games v and CAD / CAM systems.

6) Light Pen : It is an input device that use a light sensitive detector to select objects directly on a display screen using a pen. Light pen has a photocell placed in a small tube. By using light pen, we can locate the exact position on the screen.

7) Scanner : It is used to read text or pictures . printed on paper and translate the information into computer usable form. It is just like a photostat machine but it gives information to the computer.

8) Digital Camera : By using digital camera, we can take photographs and store in a computer. Therefore we can reduce the use of film. Hence it is economical.

9) Touchpad: It is a pointing device found on the portable computers(lap top). Just like a mouse it consists of two buttons below the touch surface to do the operations like left click and right click. By using our fingers we can easily operate.

10) Microphone :“By using this device we can convert voice signals into digital form.

11) Biometric sensor: It is used to read unique human physical features like finger prints,retina, iris pattern, facial expressions etc. Most of you give these data to the Government for Aadhaar.

12) Smart card, reader: A plastic card(may be Iik6 your ATM. card) stores and transmit data with the help of a reader.

13) Digital Camera : By using digital camera, we can take photographs and store in a computer. Therefore we can reduce the use of film. Hence it is economical.

Question 2.
Briefly explain the various visual display units.
Answer:
The visual display units are given below:

1) Cathode Ray Tube (CRT) : There are two types of CRT’s, monochrome (Black and white) and colour. Monochrome CRT consists of one electron gun but colour CRT consists of 3 electron guns (Red, Green and Blue) at one end and the other end coated with phosphor. It is a vacuum tube. The phosphor coated screen can glow when electron beams produced by electron guns hit. It is possible to create all the colours using Reef, Green and Blue. The images produced by this is refreshed at the rate of 50 or 60 times each second. Its disadvantage is it is heavy and bulky. It consumes more power and emits heat. But it is cheap. Nowadays its production is stopped by the company.

2) Liquid Crystal Display (LCD): It consists of two electrically conducting plates filled with liquid crystal. The front plate has transparent electrodes and the back plate is a mirror. By applying proper electrical signals across the plates, the liquid crystals either transmit or block the light and then reflecting it back from the mirror to the viewer afrid hence produce images. It is used in where small sized displays are required.

3) Light Emitting Diode(LED): It uses LED behind the liquid crystals in order to light up the screen.
It gives a better quality and clear image with wider viewing angle. Its power consumption is less.

4) Plasma Panels : It consists of two glass plates filled with neon gas. Each plate has several parallel electrodes, right angles to each other. When low voltage is applied between two electrodes, one on each plate, a small portion of gas is glow and hence produce images. Plasma displays provide high resolution but are expensive. It is used in, where quality and size is a matter of concern.

5) Organic Light Emitting Diode(OLED) Monitors: It is made up of millions of tiny LEDs. OLED monitors are thinner and lighter than LCDs and LEDs. It consumes less power and produce better quality images but it is very expensive.

Question 3.
Your friend wants to buy a printer. He wants to know more about printers. Explain different types of printers.
Answer:
Printer: There are two types of printers impact and non impact printers. Printers are used to produce hard copy.
Impact Printers: There is a mechanical contact be-tween print head and the paper.

1) Dot Matrix Printer: Here characters are formed by using dots. The printing head contains a vertical array of pins. The letters are formed by using 5 dot rows and 7 dot columns. Such a pattern is called 5 x 7 matrix. This head moves across the paper, the selected pins fire against an inked ribbon to form characters by dot. They are capable of faster printing, but their quality is not good.

2) Non-impact Printers : There is no mechanical contact between print head and paper so Carbon copies cannot be possible to take. They are inkjet, laser, thermal printers etc.

a) Ink jet Printer: It works in the same fashion as dot matrix printers, but the dots are formed with tiny droplets of ink to be fired from a bottle through a nozzle. These droplets are deflected by an electric field using horizontal and vertical deflection plates to form Characters and images. It is possible to generate colour output. They produce less noise and produce high quality printing output. The printing cost is higher. Here liquid ink is used.

b) Laser Printer: It uses photo copying technology. Here instead of liquid ink dry ink powder called toner is used. A drum coated with positively charged photo conductive material is scanned by a laser beam. The positive charges that are illuminated by the beam are dissipated. The drum is then rolled through a reservoir of negatively charged toner which is picked up by the charged portions of the drum. It adheres to the positive charges and hence creating a page image on the drum. Monochrome laser printer uses a single toner. whereas the colour, laser printer uses four toners. Its print quality is good less noise and printing cost is higher.

c) Thermal Printers : It is same as dot matrix printer but it needs heat sensitive paper. It produces images by pushing electrically heated pins to the special paper. It does not make an impact on the paper so we cannot produce carbon copies. It produce less noise, low quality print and inexpensive. It is used in fax machine.

3) Plotter: A plotter is a device that draws pictures or diagrams on paper based on commands from a computer. Plotters draw lines using a pen. Pen plotters generally use drum or flat bed paper holders. In a drum plotter the paper is mounted on the surface of a drum. Here the paper is rotated. But in a flat bed plotter the paper does not move and the pen holding mechanism provides the motion that draws pictures. Plotters are used in engineering applications where precision is needed.

4) Three Dimensional (3D) printer: This device is used to print 3D objects.

Question 4.
Your school got two printers. One dot matrix and one Laser printer through ICT scheme of Central Govt. What is the difference between these two printers? Explain. .
Answer:

Question 5.
Explain Primary Memory in detail.
Answer:
Primary memory is classified into two, Random Access Memory (RAM) and Read Only Memory (ROM). The primary memory hold? the data which is to be processed by the CPU and the set of instructions to be executed next. The CPU can access the instructions in the primary memory only.

Random Access Memory (RAM): RAM is used to store data and instructions needed by the CPU for processing. RAM can be used for both reading and writing of data so it is called Read and Write memory. It is a volatile memory, that is contents of the RAM will be lost when the power is turned off. The invention of integrated circuits (chips) increased the memory capacity and redi/ced the size and cost. Static RAM, Dynamic RAM, Synchronous Dynamic RAM (SDRAM) are the various types of RAM.

Read Only Memory (ROM) : We can read this memory but we cannot write into this memory. It is a nonvolatile memory, that is its contents will not lost when the power is turned off. This memory is stored in the ROM chip at the time of manufacturing itself hence it is called firmware. ROM contains instructions to check the hardware components connected to the system, perform some basic input/ output operations (BlbS), initiates loading of essential software. The different categories are PROM, EPROM and EE PROM.

PROM (Programmable Read Only Memory) : It is just like WORM. That meaiis the instructions are write once but read many. But we cannot change the instructions.

EPROM (Erasable Programmable Read Only Memory) : It functions just like PROM. But by using ultraviolet light we can erase the old data and can write new data.

EEPROM (Electrically Erasable Programmable Read Only Memory) : Here instead of ultraviolet light electric signals are used to erase old data ‘and write new data under software control. It is highly expensive than regular ROM chips.

Question 6.
Explain secondary memory in detail.
OR
To store large volume of data permanently. Which memory is used? Explain.
Answer:
Primary memory has a limited storage capacity and it is not permanent that is why to store large volume of data permanently secondary memory or storage devices are used. They are of many types . and they vary in the capacity of storage, speed of data access and media of storage. Nowadays magnetic disks and optical disks are commonly used.

1) Magnetic Disk : Magnetic disk allows the storage and retrieval for contents of the disk from anywhere at a moderate speed. Magnetic Disks available in various size and storage capacity but the storage media and data access mechanism are similar. The storage media is circular platters or disks coated with magnetic material.

It consists of a spindle capable of rotating with .the help of an electrical motor and a read/write head,
a) Floppy disk : Floppy means flexible or soft, it uses flexible disk. Its storage capacity is 1.44MB and slower in data transfer rate.
b) Hard Disk : Instead of flexible or soft disk it uses rigid material hence the name hard disk. Its storage capacity and data transfer rate are high and low access time. These are more lasting and less error prone. The accessing mechanism and storage media are combined together in a single unit and connect to the mother board via cable.
Therefore we call it as hard disk drive (HDD). It contains one or more rigid platters coated both sides with a special magnetic material and a spindle. Datas are recorded on either surface of the disk except the outer side of last and first disk. Each surface will have one or more read/write heads (fixed head or movable head). The spindle is attached to a motor that rotates at high speed typically 7200 rotation per minute (rpm). A floppy disk rotates only at 300 rpm.

2) Optical Disk: The high power laser uses a concentrated, narrow beam of light, which is focuses and directed with lenses, prisms and mirrors for recording data. The optical disks are given below:

a) Compact Disk Read Only Memory (CDROM): The data in CDROM is imprinted by the manufacturers. The user cannot erase or write on the disk but user can only read its contents. CDROM is written in a single continuous spiral unlike magnetic disks that uses concentric qrcles. Its storage capacity is 700MB.

b) Erasable Optical Disk: The disadvantage of CDROM is that we cannot change or erase the contents. But erasable disks can be changed and erased.

c) Digital Versatile Disk: It is capable of storing upto 4.7GB and more faster.

d) Blu-ray Disc: It is used to read and write High Definition video data as well as to store very huge amount of data. While Cd and DVD uses red laser to read and write but it uses Blue- Violet laser, hence the name Blu ray disc. The blue violet laser has shorter wave length than a red laser so it can pack more data tightly.

3) Semiconductor storage (Flash memory): It uses EEPROM chips. It is faster and long lasting.

a) USB flash drive: It is also called thumb drive or pen drive. Its capacity varies from 2 GB to 32 GB.
b) Flash memory cards : It is used in Camera, Mobile phones, tablets etc to store all types of data.

Question 7.
What do you mean by a computer software? Mention its different classification.
OR
Your friend wants to know more about software. Explain more about different classification.
OR
Your friend told you that COBOL and MS Word are same softwares. Do you agree with him. Explain. What is a software and its classification ?
Answer:
A Software is a collection of programs to perform a task. The softwares can be classified into two major groups,
1) System software
2) Application software

I. System Software

It is a collection of programs used to manage system resources and control its operations. It is further classified into two.
a) Operating System
b) Language Processor

a) 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.

b) Language Processes : We know that a program is a set of instructions. The instructions to the computer are written in different languages. They are high level language (HLL) and low level language. In HLL english like statements are used to write programs. They are C, COBOL, PASCAL, VB, Java etc. HLL is very easy and can be easily understood by the human being.

Low level language are classifed into Assembly Language and Machine Language.
In assembly language mnemonics (codes) are used to write programs

In Machine Language 0’s and 1’s are used to write program. It is very difficult but this is the only language which is understood by the computer. Usually programmers prefer HLL to write programs because of its simplicity. But computer understands only machine language. So there is a translation needed. The program which perform this job are language processors. 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.

II. Application Software

Programs developed to serve a particular application is known as application software,
eg:– MS Office, Compression Utility, Tally etc.
Application software can further be sub divided into three categories.
a) Packages
b) Utilities
c) Customized Software
a) Packages: Application software that makes the computer useful for people to do every task. Pack-ages are used to do general purpose application.
They are given below:

1) Word Processes : This is used for creation and modification of text document. That means a word processor helps the people to create, edit and format a textual data with less effort and maximum efficiency. By using word processor we can change font and font size of character, change alignment (left, right, center and justify), check spelling and grammar of the whole document etc.
eg:- MS Word.

2) Spread Sheets : It contains data or information in rows and columns and can perform calculation (Arithmetic, Relational and logical operation). It helps to calculate results of a particular formula and the formula can apply different cells (A cell is the intersection of a row and column. Each column carries an alphabet for its name and row is numbered). It is used to prepare budgets, balance sheets, P & L account, Pay roll etc. We can easily prepare graphs and charts using data entered in a worksheet. A file is a work book that contains one or more work sheets,
eg :- MS Excel is a spread sheet software.

3) Presentation and Graphics: You can present your idea with sound and visual effects with the help of presentation software by preparing slides. The application software that manipulate visual images is known as graphics software.
Eg:- MS Power Point is a presentation package.

4) Data base package : Data base is a collection of large volume of data. DBMS is a set of programs that manages the datas are for the centralised control of data such that creating new records to the database, deleting, records whenever not wanted from the database and modification of the existing database.
Example for a DBMS is MS Access.

5) Utilities : Utilities are programs which are designed to assist computer for its smooth functioning.
The utilities are given below:

1) Text editor: It is used for creating and editing text files.
2) Backup utility : Creating a copy of files in another location to protect them against loss, if your hard disk fails or you accidently overwrite or delete data.
3) Compression Utility : It is used to reduce the size of a file by using a program and can be restored to its original form when needed.
4) Disk Defragmenter: It is used to speeds up disk access by rearranging the files that are stored in different locations as fragments to contiguous memory and free space is consolidated in one contiguous block
5) Vims Scanner: It is a program called antivirus ” software scans the disk for viruses and removes them if any virus is found.

c) Customised software: It is collection of programs which are developed to meet user needs to serve a particular application. It is also called tailor made software

Question 8.
To use a computer not only the hardware but also software are required. Explain the classification of software.
Answer:
Software : The set of instructions that tell the hardware how to perform a task is called software. Without software computer cannot do anything.
Two types System s/w and Application s/w System software :
It is a collection of programs used to manage system resources and control its operations.
It is further classified into two.
a) Operating System
b) Language Processor
a) 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

i) Process management: It includes allocation and de allocation of processes(program in execution) as well as scheduling system resources in efficient manner
ii) Memory management : It takes care of allocation and de allocation of memory in efficient manner
iii) File management : This includes organizing, naming , storing, retrieving, sharing, protecting and recovery of files.
iv) Device management : Many devices are connected to a computer so it must be handled efficiently.

b) Language Processes : We know that a program is a set of instructions. The instructions to the computer are written in different languages. They are high level language (HLL) and low level language. In HLL English like statements are used to write programs. They are C, C++, COBOL, PASCAL, VB, Java etc. HLL is very easy and can be easily understood by the human being.
Low level language are classified into Assembly Language and Machine Language.
In assembly language mnemonics (codes) are used to write programs

In Machine Language 0’s and 1 ’s are used to write program. It is very difficult but this is the only language which is understood by the computer. Usually programmers prefer HLL to write programs because of its simplicity. But computer understands only machine language. So there is a translation needed. The program which perform this job are language processors. 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.

II. Application Software

Programs developed to serve a particular application is known as application software. eg:- MS Office, Compression Utility, Tally etc. Application software can further be sub divided into three categories.
a) Packages
b) Utilities
c) Customized Software

a) Packages: Application software that makes the computer useful for people to do every task. Packages are used to do general purpose application.
They are given below:

1) Word Processes : This is used for creation and . modification of text document. That means a word processor helps the people to create,, edit and format a textual data with less effort and maximum efficiency. By using word processor we can change font and font size of character, change alignment (left, right, center and justify), check spelling and grammar of the whole document etc.
eg:-MS Word.

2) Spread Sheets : It contains data or information in rows and columns and can perform calculation (Arithmetic, Relational and logical operation). It helps to calculate results of a particular formula and the formula can apply different cells (A cell is the intersection of a row and column. Each column carries an alphabet for its name and row is numbered). It is used to prepare budgets, balance sheets, P & L account, Pay rolj etc. We can easily prepare graphs and charts using data entered in a worksheet. A file is a work book that contains one or more work sheets,
eg :- MS Excel is a spread sheet software.

3) Presentation and Graphics : You can present your idea with sound and visual effects with the help of presentation software by preparing slides. The application software that manipulate visual images is known as graphics softvyare,
Eg: MS Power Point is’a presentation package.

4) Data base package: Data base is a collection of large volume of data. DBMS is a set of programs that manages the datas are for the centralized control of data such that creating new, records to the database, deleting, records whenever not wanted from the database and modification of the. existing database.
Example for a DBMS is MS Access.

5) DTP Packages : DTP means Desk Top Publishing. By using this we can create books, periodicals, magazines etc. easily and fastly. Now DTP packages are used to create in Malayalam also,
eg:- PageMaker.

6) Utilities : Utilities are programs which are designed to assist computer for its smooth functioning.
The utilities are given below:

1) Text editor: It is used for creating and editing text files.
2) Backup utility : Creating a copy of files in another location to protect them against loss, if your hard disk fails or you accidentally overwrite or delete data.
3) Compression Utility: It is used to reduce the size of a file by using a program and can be restored to.its original form when needed.
4) Disk Defragmenter: It is used to speeds up disk access by rearranging the files that are stored in different locations as fragments to contiguous memory and free space is consolidated in one contiguous block.
5) Virus Scanner: It is a program called antivirus software scans the disk for viruses and removes them if any virus is found.
c) Specific purpose software (Customized software): It is collection of programs which are developed to meet user needs to serve a particular application. It is also called tailor made software.

Question 9.
Describe the different types of memories and memory devices in computer with features and examples.
Answer:
Storage Unit(Memory Unit): A computer has huge storage capacity. It is used to store data and instructions before starts the processing. Secondly it stores the intermediate results and thirdly it stores information(processed data), that is the final results before send to the output unit(Visual Display Unit, Printer, etc)

Two Types of storage unit
i) Primary Storage alias Main Memory: It is further be classified into Two – Random Access Memory (RAM) and Read Only Memory(ROM). The one and only memory that the CPU can directly access is the main memory at a very high speed. It is expensive hence storage capacity is less. RAM is volatile(when the power is switched off the content will be erased) in nature but ROM is non volatile(lt is permanent). In ROM a “boot up” program called BIOS(Basic Input Output System) is stored to “boots up” the computer when it switched on. Some ROMs are given below.

1) PROM(Programmable ROM) : It is programmed at the time of manufacturing and cannot be erased
2) EPROM (Erasable PROM): It can be erased and can be reprogrammed using special electronic circuit.
3) EEPROM (Electrically EPROM) : It can be . erased and rewritten electrically

Cache Memory : The processor is a very high speed memory but comparatively RAM is slower than Processor. So there is a speed mismatch between the RAM and Processor, to resolve this a highspeed memory is placed in between these two this memory is called cache memory. Commonly used cache memories are Level(L1) Cache(128 KB), L2(1 MB),L3(8 MB), L4(128MB).

ii) Secondary Storage alias Auxiliary Memory : Because of limited storage capacity of primary memory its need arises. When a user saves a file, it will be stored in this memory hence it is permanent in nature and its capacity is huge. Eg: Hard Disc Drive(HQD), Compact Disc(CD), DVD, Pen Drive, Blu Ray Disc etc.

i) Magnetic storage device: It uses plastic tape or metal/plastic discs coated with magnetic material.
Hard Disk : Instead of flexible or soft disk it uses rigid material hence the name hard disk. Its storage capacity and data transfer rate are high and low access time. These are more lasting and less error prone. The accessing mechanism and storage media are combined together in a single unit and connect to the mother board via cable.

ii) Optical storage device.
Optical Disk : The high power laser uses a concentrated, narrow beam of light, which is focuses and directed with lenses, prisms and mirrors for recording data. This beams burns very very small spots in master disk, which is used for making molds and these molds are used for making copies on plastic disks. A thin layer of aluminium followed by a transparent plastic layer is deposited on it. The holes made by the laser beam are called pits, interpreted as bit 0 and unburned areas are called lands interpreted as bit 1. Lower power laser beam is used to retrieve the data.

DVD(Digital Versatile Disc) : It is similar to CD but its storage capacity is much higher. The capacity of a DVD starts from 4.7 GB

Blu-ray Disc : It is used to read and write High Definition video data as well as to store very huge amount of data. While Cd and DVD uses red laserto read and write but it uses Blue-Violet laser, hence the name Blu ray disc. The blue violet laser has shorter wave length than a red laser so it can pack more data tightly.

iii) Semiconductor storage (Flash memory): It uses EEPROM chips. It is faster and long lasting.
USB flash drive: It is also called thumb drive or pen drive. Its capacity varies from 2 GB to 32 GB.
Flash memory cards: It is used in Camera, Mobile phones, tablets etc to store all types of data.

Question 10.
Explain how e-Waste creates environmental issues. Usually there are four methods for e-Waste dispoal.
Which one is the most effective? Why? Write a slogan to aware the public about e-Waste hazards.
Answer:
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 Q 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 11.
With the help of a block diagram, explain the functional units of a computer.
Answer:
Functional units of computer
A computer is not a single unit but it consists of many functional units(intended to perform jobs) such as Input unit,Central Processing Unit(ALU and Control Unit), Storage (Memory) Unit and Output Unit.

1) Input Unit : Its aim is to supply data (Alphanumeric, image , audio, video, etc.) to the computer for processing. The Input devices are keyboard, mouse, scanner,mic, camera,etc

2) Central Processing Unit (CPU): It is the brain of the computer and consists of three components
Arithmetic Logic Unit(ALU) – As the name implies it performs all calculations and comparison operations.
Control Unit(CU)- It controls over all functions of a computer
Registers- it stores the intermediate results temporarily.

3. Storage Unit(Memory Unit): A computer has huge storage capacity. It is used to store data and instructions before starts the processing. Secondly it stores the intermediate results and thirdly it stores information(processed data), that is the final results before send to the output unit(Visual Display Unit, Printer, etc) .

Two Types of storage unit

i. Primary Storage alias Main Memory : It is further be classified into Two- Random Access Memory(RAM) and Read Only Memory(ROM). The one and only memory that the CPU can directly access is the main memory at a very high speed. It is expensive hence storage capacity is less. RAM is volatile (when the power is switched off the content will be erased) in nature but ROM is non volatile(It is permanent).

ii. Secondary Storage alias Auxiliary Memory: Because of limited storage capacity of primary memory its need arises. When a user saves a file, it will be stored in this memory hence it is permanent in nature and its capacity is huge.
Eg: Hard Disc Drive(HDD), Compact Disc(CD), DVD, Pen Drive,Blu Ray Disc etc.

4. Output Unit: After processing the data we will get information as result, that will be given to the end user through the output unit in a human readable form. Normally monitor and printer are used.

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Kerala Plus One Economics Notes Chapter 19 Uses of Statistical Methods

Project and Project Report
Project means a plan or programme, capable of analysis, planning and implementation. There are professional and academic projects. A professional project will have definite objectives, an area of implementation, and a time period within which it will be executed.

An academic project is purely an academic exercise to study a problem. It may or may not have practical application. Developing a project by conducting a survey and preparing a report will help in analyzing relevant information and suggesting improvements in a product or system. Students, researchers, marketing groups, etc., undertake such projects. Reports of such studies are called project reports.

Steps Towards Making a Project
The steps towards making a project are discussed below:
Identifying a problem or an area of study: You should be clear about what you want to study. The objective of the project has to be clearly stated. For instance, you may like to study consumer spending among households, water or electricity problems relating to households in an area and the like.

Choice of the target group: After that, you must identify the target group. If your project relates to books, then your target group will mainly be students. For the project studies of consumer projects like toothpaste, soap etc. all rural and urban populations form the target group. So the choice of target group is very important while undertaking a project.

Collection of data: Next comes the data collection. Data for the study may be collected from primary sources or secondary sources. If the data are primary a questionnaire or an interview schedule should be prepared. Telephone, postal method, e-mail, etc. may also be adopted. Secondary data are available from published and unpublished sources. Which type of data are to be used depends on the nature of your project study.

Organisation and presentation of data: After collecting the data by using various methods, the next step is to present them in a systematic manner. This is done with the help of tabulation and suitable diagrams, eg: bar diagrams, pie diagrams, graphs, etc.

Analysis and Interpretation: Measures of central tendency, measures of dispersion, correlation, etc. will enable you to calculate average, variation and relationship that exist among the variables. These help us in analysing and interpreting the results.

Conclusion: The last step is to draw meaningful conclusions after the analysis and interpretation of the results. Based on the results, you can predict the future and give suggestions for government policy implications.

Bibliography: This section is meant for mentioning details of all secondary sources of data used in the study. These include magazines, newspapers, research reports etc.

Structure of the Project Report
The essential elements of Project Reports, briefly.
1. Introduction: In the section of the introduction, the project is introduced. The need and significance of the project are highlighted. The relevance of the project is explained. This section gives the reader of the report an idea about the need, importance and relevance of the project.

2. Statement of the problem: Most projects in economics deal with an economic problem and attempt to find ways to solve the problem. There can be exceptions where a Project need not be related to any problem at all. Even then, the issue that is studied has to be properly and clearly defined. This is called the statement of the problem.

3. Objectives: The objectives of the project have to be clearly stated. Without being too descriptive, the objectives have to be listed and numbered.

4. Methodology: Methodology refers to the techniques and methods used in the analysis. The nature of data, sources of data, and techniques of analysis have to be clearly stated.

5. Analysis: This is the most important part of any project report. This forms the body of the project report.

6. Limitations/Constraints: No study is 100 percent perfect. Many imperfections can creep into the report due to the limitations of the study. Limitations may arise due to problems of sampling, inaccurate answers to questions, subjective factors, lack of professionalism of enumerators, lack of adaptability of secondary data, etc.

7. Conclusion: Analysis of data will facilitate the derivation of conclusion. In this section of the report, the findings and conclusion of the study are numbered and listed.

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Kerala Plus One Economics Notes Chapter 18 Index Numbers

Index Numbers
An index number is a statistical device for measuring changes in the magnitude of a group of related variables. It represents the general trend of diverging ratios, from which it is calculated. It is a measure of the average change in a group of related variables over two different situations. An index number also measures changes in the value of the variables such as prices of a specified list of commodities, the volume of production in different sectors of industry, production of various agricultural crops, cost of living, etc.

Uses of Index Numbers:

• help in the study of trends.
• help in policy formulation.
• useful in measuring the purchasing power of money.
• help in deflating various values.
• act as economic barometers.

Some Important Index Numbers
1. Consumer price index: Consumer price index (CPI), also known as the cost of living index, measures the average change in retail prices. The CPI for industrial workers is increasingly considered the appropriate indicator of general inflation, which shows the most accurate impact of price rise on the cost of living of common people.

2. Wholesale price index: The wholesale price index number indicates the change in the general price level. Unlike the CPI, it does not have any reference consumer category. It does not include items pertaining to services like barber charges, repairing, etc.

3. Industrial production index: The index number of industrial production measures changes in the level of industrial production comprising many industries. It includes the production of the public and the private sector. It is a weighted average of quantity relatives. In India, it is currently calculated every month with 1993 – 94 as the base.

4. Index number of agricultural production: Index number of agricultural production is a weighted average of quantity relatives. Its base period is the triennium ending 1981-82. In 2003-04 the index number of agricultural production was 179.5. It means that agricultural production has increased by 79.5 percent over the average of the three years 1979-80, 1980-81 and1981-82. Foodgrains have a weight of 62.92 percent in this index.

5. Producer Price Index: The producer price index number measures price changes from the producers’ perspective. It uses only basic prices including taxes, trade margins and transport costs.

Issues in the Construction of an Index Number
You should keep certain important issues in mind, while constructing an index number.
1. You need to be clear about the purpose of the index. Calculation of a volume index will be inappropriate when one needs a value index.

2. Besides this, the items are not equally important for different groups of consumers when a consumer price index is constructed.

3. Every index should have a base. This base should be as normal as possible. Extreme values should I not be selected as the base period. The period should be also not belong to too far in the past. The comparison between 1993 and 2005 is much more meaningful than a comparison between 1960 and 2005. Many items in a 1960 typical consumption basket have disappeared at present. Therefore, the base year for any index number is routinely updated.

4. Another issue is the choice of the formula, which depends on the nature of the question to be studied. The only difference between Laspeyres’ index and Paasche’s index is the weights used in these formulae.

5. Besides, there are many sources of data with different degrees of reliability. Data for poor reliability will give misleading results. Hence, due care should be taken in the collection of data. If primary data are not being used, then the most reliable source of secondary data should be chosen.

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Kerala Plus One Economics Notes Chapter 17 Correlation

Correlation
The relationship between any two or more variables is referred to as correlation. Correlation studies and measures the intensity of relationships among variables.

Positive and Negative Correlation
When the values of two variables move in the same direction, the correlation is said to be positive; and when the values of two variables move in the opposite direction, the correlation is said to be negative. That is, if the value of one variable increases with an increase (and decreases with a decrease) of the value of the other variables, they are said to be in positive correlation. Likewise, if the value of one variable increases with a decrease (and decreases with an increase) of the value of the other variable, they are said to be in negative correlation.

Techniques of measuring correlation
Scatter Diagram: A scatter diagram is a useful technique for visually examining the form of relationship, without calculating any numerical value. In this technique, the values of the two variables are plotted as points on a graph paper. The cluster of points, so plotted, is referred to as a scatter diagram. From a scatter diagram, one can get a fairly good idea of the nature of the relationship. In a scatter diagram the degree of closeness of the scatter points and their overall direction enable us to examine the relationship. If all the points lie on a line, the correlation is perfect and is said to be unity. If the scatter points are widely dispersed around the line, the correlation is low. The correlation is said to be linear if the scatter points lie near a line or on a line.

Karl Pearson’s Coefficient of Correlation: This is also known as the product-moment correlation and simple correlation coefficient. It gives a precise numerical value of the degree of linear relationship between two variables X and Y. The linear relationship may be given by Y = a + bX.

This type of relationship may be described by a straight line. The intercept that the line makes on the Y-axis is given by a and the slope of the line is given by b. It gives the change in the value of Y for very small change in the value of X. On the other hand, if the relation cannot be represented by a straight line as in Y = X² the value of the coefficient will be zero.
It clearly shows that zero correlation need not mean absence of any type of relation between the two variables.

Spearman’s Rank Correlation: Spearman’s rank correlation was developed by the British psychologist C.E. Spearman. It is used when the variables cannot be measured meaningfully as in the case of price, income, weight etc. Ranking may be more meaningful when the measurements of the variables are suspect. Consider the situation where we are required to calculate the correlation between height and weight of students in a remote village. Neither measuring rods nor weighing scales are available. The students can be easily ranked in terms of height and weight without using measuring rods and weighing scales.

Rank correlation coefficient and simple correlation coefficient have the same interpretation. Its formula has been derived from simple correlation coefficient where individual values have been replaced by ranks. These ranks are used for the calculation of correlation. This coefficient provides a measure of linear association between ranks assigned to these units, not their values. It is the Product Moment Correlation between the ranks.

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Kerala Plus One Economics Notes Chapter 16 Measures of Dispersion

Dispersion
A measure of dispersion can tell you about income inequalities, thereby improving the understanding of the relative standards of living enjoyed by different strata of society. Dispersion is the extent to which values in a distribution differ from the average of the distribution.
To quantify the extent of the variation, there are certain measures namely:

1. Range
2. Quartile Deviation
3. Mean Deviation
4. Standard Deviation
5. Lorenz Curve

Range
Range (R) is the difference between the largest (L) and the smallest value (S) in a distribution.
Thus, R = L – S
A higher value of Range implies higher dispersion and vice-versa.

Quartile Deviation
The presence of even one extremely high or low value in distribution can reduce the utility of range as a measure of dispersion. Thus, you may need a measure which is not unduly affected by the outliers. In such a situation, if the entire data is divided into four equal parts, each containing 25% of the values, we get the values of Quartiles and Median. The upper and lower quartiles (Q₃ and Q₁ respectively) are used to calculate Inter Quartile Range which is Q₃ – Q₁.

Mean Deviation
Mean deviation of a series is the arithmetic average of the deviations of various items from a measure of central tendency. In aggregating the deviations, algebraic signs of the deviations are not taken into account. It is because, if the algebraic signs were taken into account, the sum of deviations from the mean should be zero and that from the median is nearly zero. Theoretically, the deviations can be taken from any of the three averages, namely, arithmetic mean, median, or mode; but, the mode is usually not considered as it is less stable. Between mean and median, the latter is supposed to be better because the sum of the deviations from the median is less than the sum of the deviations from the mean,
Co-efficient of MD = \(\frac{\mathrm{MD}}{\text { Average }}\)

Standard Deviation
Standard deviation is defined as the square root of the arithmetic average of the squares of deviations taken from the arithmetic average of a series. It is also known as the root-mean-square deviation for the reason that it is the square root of the mean of the squared deviations from AM.

Standard deviation is denoted by the Greek letter a (small letter ‘sigma’). The term variance is used to describe the square of the standard deviation. Standard deviation is an absolute measure of dispersion. The corresponding relative measure is called the coefficient of SD. The coefficient of variation is also a relative measure. A series with more coefficient of variation is regarded as less consistent or less stable than a series with less coefficient of variation.
Symbolically, Standard deviation = σ
Variance = σ²
Coefficient of SD = \(\frac{\sigma}{\bar{x}}\)
Coefficient of variation = \(\frac{\sigma}{\bar{x}} \times 100\)

Lorenz Curve
The measures of dispersion discussed so far give a numerical value of dispersion. A graphical measure called the Lorenz Curve is available for estimating dispersion.

Lorenz Curve uses the information expressed in a cumulative manner to indicate the degree of variability. It is especially useful in comparing the variability of two or more distributions.

Construction of the Lorenz Curve
Following steps are required for the Construction of the Lorenz Curve

1. Calculate class mid-points and find cumulative totals
2. Calculate cumulative frequencies
3. Express the grand totals and convert the cumulative totals into percentages,
4. Now, on the graph paper, take the cumulative percentages of the variable (incomes) on the Y-axis and cumulative percentages of frequencies (number of employees) on the X-axis.
5. Draw a line joining Co-ordinate (0, 0) with (100, 100). This is called the line of equal distribution.
6. Plot the cumulative percentages of the variable with corresponding cumulative percentages of frequency. Join these points to get the curve.

Students can Download Chapter 15 Measures of Central Tendency Notes, Plus One Economics Notes helps you to revise the complete Kerala State Syllabus and score more marks in your examinations.

Kerala Plus One Economics Notes Chapter 15 Measures of Central Tendency

Measures of Central Tendency
The measuring of central tendency is a way of summarizing the data in the form of a typical or representative value. There are several statistical measures of central tendency or “averages”.
The three most commonly used averages are:

• Arithmetic Mean
• Median
• Mode

Arithmetic Mean
Arithmetic mean is the most commonly used measure of central tendency. It is defined as the sum of the values of all observations divided by the number of observations and is usually denoted by x. In general, if there are N observations as x₁, x₂, x₃,……, x_N, then the Arithmetic Mean is given by

Individual Series
In individual series, values of the variables are given individually without any group, classes, or frequency.
In this case, as stated above, finding the arithmetic mean is to add all the individual values and then divide the sum by the total number of observations and is known as the direct method.

Discrete Series
Here, the data are in the grouped form and frequency for each observation is given. But it is not in the form of classes. Here also we use direct method or assumed mean method or step deviation method to find the arithmetic mean. If a particular method is not insisted, you can follow any method which is suitable for the problem.
In this method, mean \(\bar{x}=\frac{\varepsilon f x}{N}\)

Continuous Series: In continuous series, data are given in frequency classes. The mid-value (m) of the class has to be found out first.
Mean \(\bar{x}=\frac{\varepsilon f x}{N}\)

Median
Median is that positional value of the variable which divides the distribution into two equal parts, one part comprises all values greater than or equal to the median value and the other comprises all values less than or equal to it. The Median is the “middle” element when the data set is arranged in order of magnitude.

Individual Series: For finding the median of an individual series, first arrange it in ascending or descending order and then locate the middlemost item. The value of the middlemost item will be the median.
Median = value of \(\left(\frac{N+1}{2}\right)\)th item

Discrete Series: In discrete series items are grouped and frequencies are given. There will not be any classes. For finding the median of a discrete series, first we arrange the items in ascending or descending order as before. Then, we find less than cumulative frequencies. Now, it is easy to locate the value of \(\left(\frac{N+1}{2}\right)\)th item.

Continuous Series: In Continuous series, data is given in frequency classes. For finding the median, first we identify the median class. Median class is the class in which the value corresponding to the frequency (N/2)th item may lie. After identifying the median class, we use the following formula for finding the median:

Where,
L = lower limit of the median class
N = total frequency
cf = cumulative frequency of the class preceding the median class
f = frequency of the median class
c = class width of the median class

Mode
Mode is the value around which there is the greatest concentration of values. In other words, it is the item having the largest frequency. In some cases, there may be more than one point of concentration of values and the series may be bi-modal or multi-modal. When one value occurs more frequently than any other value, the distribution is called uni-modal.

The word mode is derived from the French word ‘la mode’ which means fashion or the most popular phenomenon. Mode is thus the most popular item of a series around which there is the highest frequency density. It is denoted by Mo.

i) Individual Series: Comparing to mean and median, computation of mode is easy. In individual series, the mode is that value which repeats the highest number of times. It is often found by mere inspection.

ii) Discrete Series: In discrete series, the mode is determined just by inspection. The item having the highest frequency is taken as mode.

iii) Continuous Series: In continuous series, mode lies in the class having the highest frequency. Hence the modal class may be determined either by inspection or by grouping table. Then mode is determined using the formula:

where,
L₀ = lower limit of the modal class
D₁ = difference between the frequencies of the modal class and the class preceding it (ignoring the sign)
D₂ = difference between the frequencies of the modal class and the class succeeding it (ignoring the sign); and
c = class interval of the modal class

Quartiles
Quartiles are the measures which divide the data into four equal parts; each portion contains an equal number of observations. Thus, there are three quartiles. The first Quartile (denoted by Q₁) or lower quartile has 25% of the items of the distribution below it and 75% of the items are greater than it. The second Quartile (denoted by Q₂) or median has 50% of items below it and 50% of the observations above it. The third Quartile (denoted by Q₃) or upper Quartile has 75% of the items of the distribution below it and 25%of the items above it. Thus, Q₁ and Q₃ denote the two limits within which central 50% of the data lies.

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Kerala Plus One Economics Notes Chapter 14 Presentation of Data

Presentation of Data
The most common form of presenting the data are textual or descriptive presentation, tabular presentation and diagrammatic presentation.

Textual Presentation of Data: This is the method of presenting data in text form. This method of presentation is possible only when the quantity of data is not too large. Following are the two examples of presenting the data in a textual format appeared in news papers.

Tabular Presentation of Data: Tabular presentation is the systematic arrangement of data in rows and columns. In other words, tabulation is a layout of figures in rectangular form with appropriate heading to explain different rows and columns.

Diagrammatic and Graphical Representation of Data: It is the more attractive and eye-catching method of presenting data. This provides the quickest understanding of the actual situation to be explained by data in comparison to tabular or textual presentations. The diagrams are broadly divided into three namely geometric diagrams, frequency diagram and arithmetic line graph. Again, geometric diagrams are classified into bar diagram and pie diagram.

Parts of a Table
A good table should have the following parts.
i) Table Number: Table number is essential for identifying the table; especially when more than one table is presented. It is the table numberthat distinguishes one table from the other. For easy reference, they are numbered according to their order of appearance in the text. It may be placed at the top or at the bottom)

ii) Title: Every table should contain a title, because it narrates about the contents of the table. Just like the table number, the title can also be placed at the top or bottom of the table. The title should be clear, brief, carefully worded, unambiguous and complete. It should be capable of giving the clear idea about the table.

iii) Captions: It is also called the column heading, which gives a designation to the column. It is given as the top row. Under each column head, there may be subheads. In table-14.4 above, there are three captions: rank, name of country and production of wheat.

iv) Stubs: It is also called the row heading, which gives a designation to the row. It is given as the left column and that column is called the stub column.

v) Body of the Table: It is the most important part of the table. It contains the actual data. The body is arranged generally from left to right in rows and from top to bottom in columns.

vi) Unit of Measurement: The units of measurement of the figures in the data should always be given in the table. It can be given with the title if the same unit is used in the whole table. If different units are used for different columns, they should be given with the respective column headings; and if different units are used for different rows, they should be given with the respective row headings.

vii) Source: It is a brief statement indicating the source from where the data is taken. If more than one source, all of them should be written there. This will help the reader to check the figures and gather more information if required. It also helps in indicating the authenticity of data. Generally, source is written in the bottom of the table.

Various Kinds of Diagrams
There are various kinds of diagrams in common use. Amongst them the important ones are the following:
1. Geometric diagram
2. Frequency diagram
3. Arithmetic line graph

Geometric Diagram: Bardiagram and pie diagram come in the category of geometric diagram for the presentation of data. The bar diagrams are of three types- simple, multiple and component bar diagrams.

i) Bar Diagram
Simple Bar Diagram: Bardiagram comprises a group of Equi-spaced and equi-width rectangular bars for each class or category of data. The height or length of the bar reads the magnitude of data.

Multiple Bar Diagram: Multiple bar diagrams are used for comparing two or more sets of data, for example, import and export for different years, marks obtained in different subjects in different classes, etc.

Component Bar Diagram: Component bar diagrams or charts also called sub-diagrams are very useful in comparing the sizes of different component parts and also for throwing light on the relationship among these integral parts.

ii) Pie Diagram
A pie diagram is also a component diagram, but unlike a component bar diagram, a circle whose area is proportionally divided among the components it represents. It is also called a pie chart. The circle is divided into as many parts as there are components by drawing straight lines from the centre to the circumference. Pie charts usually are not drawn with absolute values of a category. The values of each category are first
expressed as a percentage of the total value of all the categories.

It may be interesting to note that data represented by a component^bar diagram can also be represented equally well by a pie chart, the only requirement being that absolute values of the components have to be converted into percentages before they can be used for a pie diagram.

Graphical Presentation
Data in the form of grouped frequency distributions are generally represented by frequency diagrams like histogram, frequency polygon, frequency curve and ogive.

a) Histogram: A histogram is a two-dimensional diagram. It is a set of rectangles with bases as the intervals between class boundaries (along X- axis) and with areas proportional to the class frequency. If the class intervals are of equal width, which they generally are, the area of the rectangles are proportional to their respective frequencies. However, in some type of data, it is convenient, at times necessary, to use varying width of class intervals. The width in a histogram is as important as its height. We can have a bar diagram both for discrete and continuous variables, but histogram is drawn only for a continuous variable. Histogram also gives value of mode of the frequency distribution graphically.

b) Frequency Polygon: A frequency polygon is a plane bounded by straight lines, usually four or more lines. Frequency polygon is an alternative to histogram and is also derived from histogram itself. A frequency polygon can be fitted to a histogram for studying the shape of the curve. The simplest method of drawing a frequency polygon is to join the midpoints of the topside of the consecutive rectangles of the histogram.

c) Frequency Curve: The frequency curve is obtained by drawing a smooth freehand curve passing through the points of the frequency polygon as closely as possible. It may not necessarily pass through all the points of the frequency polygon but it passes through them as closely as possible.

d) Ogive: Ogive is also called cumulative frequency curve. As there are two types of cumulative frequencies, for example less than type and more than type, accordingly there are two ogives for any grouped frequency distribution data. Here in place of simple frequencies as in the case of frequency polygon, cumulative frequencies are plotted along y-axis against class limits of the frequency distribution. For less than give the cumulative frequencies are plotted against the respective upper limits of the class intervals whereas for more than ogives the cumulative frequencies are plotted against the respective lower limits of the class interval. An interesting feature of the two ogives together is that their intersection point gives the median.

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Kerala Plus One Economics Notes Chapter 13 Organisation of Data

Classification of Data
The groups or classes of classification can be done in various ways. The way you want to classify them would depend on your requirement. Likewise, the raw data could be classified in various ways depending on the purpose at hand.

1. Chronological Classification: They can be grouped according to time. Such a classification is known as a Chronological Classification. In such a classification, data are classified either in ascending or in descending order with reference to time such as years, quarters, months, weeks, etc. The variable ‘population’ is a Time Series as it depicts a series of values for different years.

2. Spatial Classification: In Spatial Classification the data are classified with reference to geographical locations such as countries, states, cities, districts, etc.

3. Qualitative Classification: Sometimes you come across characteristics that cannot be expressed quantitatively. Such characteristics are called Qualities or Attributes. For example, nationality, literacy, religion, gender, marital status etc. They cannot be measured. Yet these attributes can be classified on the basis of either the presence or the absence of a qualitative characteristic. Such a classification of data on attributes is called a qualitative classification.

4. Quantitative Classification: Characteristics like height, weight, age, income, marks of students, etc. are quantitative in nature. When the collected data of such characteristics are grouped into classes, the classification is a Quantitative Classification.

Continuous and discrete variable
A variable is that characteristic whose value is capable of changing from unit to unit. Variables can be continuous or discrete. A continuous variable is that which can take any value in a specified interval. Whereas discrete variables are those which can assume only certain values.

Exclusive and Inclusive Methods
Exclusive Method: Under the method, the upper-class limit is excluded but the lower class limit of a class is included in the interval. Thus an observation that is exactly equal to the upper-class limit, according to the method, would not be included in that class but would be included in the next class. On the other hand, if it were equal to the lower class limit then it would be included in that class.

Inclusive Method: There is another method of forming classes and it is known as the Inclusive Method of classification. In comparison to the exclusive method, the Inclusive Method does not exclude the upper-class limit in a class interval. It includes the upper class in a class. Thus both class limits are parts of the class interval.

Frequency Array
For a discrete variable, the classification of its data is known as a Frequency Array. Since a discrete variable takes values and not intermediate fractional values between two integral values, we have frequencies that correspond to each of its integral values.

Frequency Distribution
A frequency distribution is a comprehensive way to classify raw data of a quantitative variable. It shows how the different values of a variable are distributed in different classes along with their corresponding class frequencies.

Each class in a frequency distribution table is bounded by Class Limits. Class limits are the two ends of a class. The lowest value is called the Lower Class Limit and the highest value the Upper-Class Limit.

Class Interval or Class Width is the difference between the upper-class limit and the lower class limit. For class 60-70, the class interval is 10 (upper-class limit minus lower class limit).

The Class Midpoint or Class Mark is the middle value of a class. It lies halfway between the lower class limit and the upper-class limit of a class and can be ascertained in the following manner:

Class Midpoint or Class Mark = (Upper-Class Limit + Lower Class Limit)/2

The classmark or mid-value of each class is used to represent the class. Once raw data are grouped into classes, individual observations are not used in further calculations. Instead, the classmark is used. Frequency Curve is a Graphic representation of a frequency distribution.

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Kerala Plus One Economics Notes Chapter 12 Collection of Data

Sources of Data
Statistical data can be obtained from two sources. The enumerator may collect the data by conducting an inquiry or an investigation. Such data are called Primary Data, as they are based on first-hand information.
If the data have been collected and processed by some other agency, they are called Secondary Data. Generally, the published data are secondary data.

Methods of Collecting Primary Data
There are three basic ways of collecting data:

1. Personal Interviews
2. Mailing (questionnaire) Surveys
3. Telephone Interviews

1. Personal Interviews: This method is used when the researcher has access to all the members. The researcher conducts face to face interviews with the respondents. Personal contact is made between the respondent and the interviewer. The interviewer has the opportunity of explaining the study and answering any query of the respondents.

2. Mailing Questionnaire: When the data in a survey are collected by mail, the questionnaire is sent to each individual by mail with a request to complete and return it by a given date. The advantages of this method are that it is less expensive. It allows the researcher to have access to people in remote areas too, who might be difficult to reach in person or by telephone. It does not allow the influence of the respondents by the interviewer. It also permits the respondents to take sufficient time to give thoughtful answers to the questions.

3. Telephone Interviews: In a telephone interview, the investigator asks questions overthe telephone. The advantages of telephone interviews are that they are cheaper than personal interviews and can be conducted in a shorter time. They allow the researcher to assist the respondent by clarifying the questions. The telephone interview is better in the cases where the respondents are reluctant to answer certain questions in personal interviews.

Collection of Secondary Data
Secondary data are those which are available in published or unpublished records. Once a decision is taken to collect secondary data, the question of sources of data arises. There are two sources for the collection of secondary data, namely, published sources and unpublished sources.
Published Sources:

• Official publications of the central, state, and local governments.
• Official publications of international agencies like the United Nations Organization and its subsidiaries.
• Reports and publications of trade associations, chambers of commerce, banks, etc.
• Reports of committees and commissions.
• Reports published in technical trade journals.
• Reports submitted by researchers, economists, etc.

Unpublished Sources:

• Unpublished materials found with research institutes, trade associations, chamber of commerce, etc.

Census Survey and Sample Survey
Under census method, we collect information from each and every unit of population relating to the problem under investigation. On the other hand, the under-sample method, rather than collecting information about all the units of population, we collect information from a few selected items from the population.

Methods of Sampling
There are various methods of selecting samples from a population. These are called sampling techniques.
The two types of sampling techniques are random sampling and non-random sampling.

Random Sampling Methods
Random sampling is a technique of drawing a sample from the population in which each and every unit of the population has an equal chance of being included in the sample. It is further divided into simple random sampling and restricted random sampling.

a) Simple random sampling: In this method, the sample is taken from the population without making any division or classification of the population. Hence, every unit of the population has an equal chance of being selected in the sample. Simple random sampling may be done either by using lottery method or by Table of random numbers.

b) Restricted random sampling: Restricted random sampling is of mainly three types. Stratified sampling, systematic sampling and cluster sampling.

1. Stratified sampling: When the population is heterogeneous, stratified sampling method is used. Under this method the whole population is divided into various groups or strata of units, such that the units in each class possess similar characteristics. For example, suppose you are studying about the consumption pattern of students in your school. The population comprises the whole students studying in various standards of your school. A student studying in standard-5 and a student studying in standard-9 may have different consumption patterns. That is, for this characteristic, the population is heterogeneous. Hence, different standards can be selected as different groups or strata. Then sample is drawn from each stratum at random.

2. Systematic sampling: A systematic sampling is formed by selecting one at random and then selecting the rest at evenly spaced intervals until the sample size has been reached. Suppose that in the nature club of your school, there are 100 members and you want to make a core group of 10. First you number the 100 students of the club from 1 to 100. By lottery method or by random table method you select one student from the first ten. Let it be the 7th student. Then take an appropriate interval and select the rest 9 students. If the interval you had taken is 10, then the second student in the sample is the 17th student, the third student in the sample is the 27th student, etc.

3. Cluster sampling: This type of sampling is carried out in several stages. Suppose we are studying about the employment of households in Kerala. In the first stage, Kerala is divided into three or four zones. Then each zone is divided into districts. Then each district is divided into villages. From each district, sample of villages may be taken at random. From each selected village, households of required size are also taken at random. Since several stages involve in cluster sampling, it is also known as multi-stage sampling.

Non-Random Sampling
In this method of sampling the investigator himself makes the choice of sample from the population according to his own discretion which he thinks to be the best. Here, all the units in the population do not have equal chance of being selected in to the sample.

Sampling Errors and Non-Sampling Errors:
Sampling Errors
The purpose of the sample is to take an estimate of the population. Sam^g error refers to the differences between the sample estimate and the actual value of a characteristic of the population. It is the error that occurs when you make an observation from the sample taken from the population. Thus, the difference between the actual value of a parameter of the population and its estimate is the sampling error.

Non-Sampling Errors
Non-sampling errors are more serious than sampling errors because a sampling error can be minimized. But errors due to mistakes while framing tables and data entry will affect the final result. They are non-sampling errors.

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Kerala Plus One Economics Notes Chapter 11 Introduction

Statistics
Statistics deals with the collection, classification analysis, and interpretation of numerical data. In our daily language, the word ‘Statistics’ is used in two distinct senses: singular and plural. In the plural sense, ‘statistics’ means ‘numerical facts systematically collected’ as described by the Oxford Dictionary. Thus, the simple meaning of statistics in the plural sense is data.

Functions of Statistics

• It simplifies the complexity of data: Complex numerical data are simplified through statistical methods.
• It reduces the bulk data: Huge data can be reduced to a few figures and thus, easily understandable.
• It adds precision in thinking: It actually sharpens one’s thinking faculty.
• It helps comparison of different sets of figures: e.g. import and export of two countries can be compared.
• It indicates trends and tendencies: Helps in making future plans.
• It helps in studying relationships between different factors: With the help of statistical methods, one can study the relation between two or more variables.
• It guides in the formulation of policies and helps in planning: Planning and policies of the government are based on statistical data.

Limitations of Statistics
The limitations of statistics are given below.

• Statistical laws are true only on average.
• Statistics can be misused.
• Statistics deals only with quantitative data.
• Statistical results lack mathematical accuracy.
• Statistical facts are collected for a pre-determined purpose.

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Kerala Plus One Economics Notes Chapter 10 Comparative Development Experience of India with its Neighbours

Development Path – A Snapshot View
India, Pakistan, and China have many similarities in their developmental strategies. India, China, and Pakistan became independent and started initiating their developmental strategies at almost the same time. India and Pakistan became independent in 1947 and China in 1949. All three countries adopted the planning strategy for economic growth and development. India’s five-year plan started in 1951, Pakistan’s in 1956 (called medium-term plan), and China’s in 1953. Government and the public sector played a major role in these economies. However, with the introduction of economic reforms in tune with globalisation the role of market was redefined. Till the 1980s, all the three economies had almost similar growth rate and other economic indicators.

China
After the establishment of the People’s Republic of China under one-party rule, all the critical sectors of the economy, enterprises, and lands owned and operated by individuals were brought under government control. The Great Leap Forward (GLF) campaign initiated in 1958 aimed at industrializing the country on a massive scale. People were encouraged to set up industries in their backyards. In rural areas, communes were started. Under the Commune system, people collectively cultivated lands.

In 1958, there were 26,000 communes covering almost all the farm population. GLF campaign met with many problems. A severe drought caused havoc in China killing about 30 million people. When Russia had conflicts with China, it withdrew its professionals who had earlier been sent to China to help in the industrialization process.

In 1965, Mao introduced the Great Proletarian Cultural Revolution (1966-76) under which students and professionals were sent to work and learn from the countryside. The present-day fast industrial growth in China can be traced back to the reforms introduced in 1978.

Pakistan
Pakistan followed the mixed economy model with, co-existence of the public sector and private sector. Pakistan also followed a protectionist policy in international trade. The introduction of the Green Revolution resulted in a rise in the production of food grains. In the 1970s, the nationalization of the capital goods industry took place. In the late 1970s and 1980stherewasashift in the economic policy in favor of de-nationalization and encouragement to the private sector.

Pakistan got substantial financial support from western nations. There was an increase in the number of emigrants and their remittance to their home country. The remittance and Western nation’s support helped the country in stimulating economic growth. In 1988 more reforms were introduced. FDI was encouraged, direct taxes were reduced and many areas of the economy were opened to private and foreign investment.

Demographic Indicators
Demographic indicators of India, China, and Pakistan can be summarised as follows:

The table shows the population growth as being highest in Pakistan, followed by India and China. Scholars point out the one-child norm introduced in China in the late 1970s as the major reason for low population growth. They also state that this measure led to a decline in the sex ratio, the proportion of females per 1000 males. However, from the table, you will notice that the sex ratio is low and biased against females in all three countries. Scholars cite son preference prevailing in all these countries as the reason. In recent times, all three countries are adopting various measures to improve the situation.

The One-child norm and the resultant arrest in the growth of the population also have other implications. For instance, after a few decades, in China, there will be more elderly people in proportion to young people. This will force China to take steps to provide social security measures with fewer workers. The fertility rate is also low in China and very high in Pakistan. Urbanization is high in both Pakistan and China with India having 28 percent of its people living in urban areas.

Indicators of Human Development
The HDI (Human Development Index) developed by UNDP (United Nations Development Programme) is an index which has universal acceptance as a good measure of the quality of human life. Since 1990 the UNDP has been publishing information related to HDI. This report ranks countries on the basis of their HDI. The following table presents some of the selected indicators of development.

Source: Human Development Report, 2014