Students must start practicing the questions from CBSE Sample Papers for Class 11 Informatics Practices with Solutions Set 5 are designed as per the revised syllabus.
CBSE Sample Papers for Class 12 Informatics Practices Set 5 with Solutions
Time Allowed: 3 hours
Maximum Marks: 70
General Instructions:
- All questions are compulsory.
- Answer the questions after carefully reading the text.
- Student has to answer only one question where choice is given.
- All programming questions have to be answered with respect to Python only.
- In Python indentation is mandatory; however, number of spaces used for indenting may vary.
- In SQL related questions – semicolon should be ignored for terminating the SQL statements,
- Use of calculators is not permitted.
SOLVED
Multiple Choice Question:
Question 1.
(i) How many types of RAM are available? [1]
(A) 3
(B) 5
(C) 2
(D) 4
Answer:
(C) 2
Explanation: There are two types of Random Access Memory or RAM. They are SRAM (Static RAM) and DRAM (Dynamic RAM). [1]
(ii) In a Python program, a control structure: [1]
(A) Defines program-specific data structures
(B) Directs the order of execution of the statements in the program
(C) Dictates what happens before the program starts and after it terminates
(D) None of the above
Answer:
(B) Directs the order of execution of the statements in the program
Explanation: Control structures determine which statements in the program will be executed and in what order, allowing for statements to be skipped over or executed repeatedly. So, option B is correct. [1]
(iii) MySQL is a/an [1]
(A) Programming Language
(B) Operating System
(C) Database Management System
(D) None of these
Answer:
(C) Database Management System
Explanation: MySQL is a language that enables the user to create and operate on relational databases. [1]
(iv) Which property of a relation is used to represent number of rows? [1]
(A) Key
(B) Attribute
(C) Degree
(D) Cardinality
Answer:
(D) Cardinality
Explanation: Cardinality is the number of rows or tuples in a relation. [1]
(v) A _____ is basically a machine capable of carrying out one or more tasks automatically with accuracy and precision. [1]
(A) Computer
(B) Simulator
(C) NLP
(D) Robot
Answer:
(D) Robot
Explanation: A robot is basically a machine capable of carrying out one or more tasks automatically with accuracy and precision. Unlike other machines, a robot is programmable, which means it can follow the instructions given through computer programs. Robots were initially conceptualized for doing repetitive industrial tasks that are boring or stressful for humans or were labor-intensive. Sensors are one of the prime components of a robot. Robot can be of many types, such as wheeled robots, legged robots, manipulators and humanoids. [1]
Question 2.
(a) How many types are computer memory? [1]
Answer:
Computer memory are of two types:
(i) Primary memory
(ii) Secondary memory [1]
(b) Write a short note on. [2]
(i) Magnetic tape
(ii) Hard disk drive.
Answer:
(i) Magnetic tape: These tapes are made of plastic film-type material coated with magnetic material to store data permanently.
(ii) Hard Disk Drive (HDD) : It is a nonvolatile, random access digital storage device. It consists of circular magnetic discs mounted over a spindle, one on top of another. Both the surfaces of all the discs except the uppermost surface of the top disc and lower surface of the lowermost disc are used for writing. Each disc is divided into concentric circles called tracks. [2]
Commonly Made Error
Students describe tracks, sectors and cylinders wrong.
Answering Tip
Try to explain all these with the help of diagrams.
(c) Write the needs of operating system. [2]
Answer:
(i) The application programs do not access the hardware resources directly. Therefore, an operating system is required to access and use the hardware resources.
(ii) Operating system provides a stable and consistent way for applications to deal with the hardware without having to know all the details of the hardware. [2]
(d) What is system software ? Explain any two system software. [4]
OR
How does a computer function?
Answer:
The software that provides the basic functionality to operate a computer by interacting directly with its constituent hardware is termed as system software. A system software knows how to operate and use different hardware components of a computer. It provides services directly to the end user or some other software. Examples of system software include –
(i) Operating System: It is the most basic system software, without which other software cannot work. The operating system manages other application programs and provides access and security to the users of the system. Some of the popular operating systems are Windows, Linux, Macintosh, Ubuntu, Android, iOS, etc.
(ii) Language Processor: Written in a HLL is a system software which processes the program to make it understandable by the computer system, as computer system can only understand machine language or binary language (also known as low level language). Assembler, interpreter and compiler are language processors used to translate low level language into high level language and vice-versa. [4]
OR
Computer performs four basic functions which are as follows:
(i) Input: Information or data that is entered into a computer is called input. It sends data and instructions to the central processing unit (CPU)
(ii) Processing: It is the sequence of actions taken on data to convert it into information which is meaningful to the user. It can be calculation, comparisons or decisions taken by the computer.
(iii) Output: It makes processed data available to the user. It is mainly used to display the desired result to the user as per input instructions.
(iv) Storage: It stores data and programs permanently. It is used to store information during the time of program execution.
Commonly Made Error:
When asked about the funtions of a computer student write about its uses.
Answering Tip:
Uses refer to application areas of a computer while functions refer to what basic operations every computer performs.
Question 3.
(a) Predict the output:
> > > print (“Python Program”) [1]
Answer:
(a) Python Program
Commonly Made Error:
Some students don’t use right syntax in python program.
Answering Tip:
Brackets are optional in some version of Python. If you do not use brackets with print, it will not be wrong.
(b) What is the method of retrieving real and imaginary parts of a complex number? [1]
Answer:
The real part of a complex number x can be retrieved as x. real and imaginary part as x.imag. [1]
(c) What are unary operators? [1]
Answer:
The operators work on only one operand are known as unary operators. [1]
(d) Write the output from the following code :
s = 0
for i in range (10,2, -2):
s = s + i
print (“sum is = “, s) [1]
Answer:
Output:
sum is = 28 [1]
(e) Write the output from the following code :
x = 1998
if x % 4 = = 0 :
print (“Leap year”)
else:
print (“Not leap year”) [2]
OR
Find the output
a = [‘a’/e’/i’/o’/u’/A’/E’/I’/O’/U’/’]
b = “Hello, have a good day”
for i in b:
if i not in a:
b = b[:b.index(i)]+b[b.index(i)+1:]
print(b) [2]
Answer:
Output:
Not leap year
(f) Write a Python program to find the sum, average marks, and percentage marks of 5 subjects and display the grade. [4]
Answer:
print (“Enter marks obtained in 5 subjects: “);
m1 = input( );
m2 = input( );
m3 = input( );
m4 = input( );
m5 = input( );
mark1 = int(m1);
mark2 = int(m2);
mark3 = int(m3);
mark4 = int(m4);
mark5 = int(m5);
sum = mark1 + mark2 + mark3 + mark4 + mark5;
average = sum/5;
percentage = (sum/500)*100;
print(“Total Marks =”, sum)
print(“Average Marks = “, average);
print(“Percentage Marks = “, percentage,”%”);
if(average>=91 and average<=100);
print(“Your Grade is A+”);
elif(average>=81 and average<=90):
print(“Your Grade is A”);
elif(average>=71 and average<=80);
print(“Your Grade is B+”);
elif(average>=61 and average<=70):
print(“Your Grade is B”);
elif(average>=51 and average<=60):
print(“Your Grade is C+”);
elif(average>=41 and average<=50):
print(“Your Grade is C”);
elif(average>=0 and average<=40):
(print(“Your Grade is F”);
else:
print(“Strange Grade..!!”); 4
Commonly Made Error:
Some students do not use colon at their proper place.
Answering Tip:
Colon must be used after conditional statements as for, while, if, etc.
Question 4.
(a) Define term Primary Key and Alternate Key. [3]
Answer:
(a) Primary key values should be unique and non-null. There can be multiple Super keys and Candidate keys in a table, but there can be only one Primary key in a table.
Alternate Key: When there are more than one candidate keys, one of the candidate key is chosen to be a primary key. The remaining candidate keys are called alternate keys. [3]
(b) Differentiate between Database state and database schema. [3]
Answer:
| Database State | Database Scheme |
| It provides the present state of the database and its data. | It gives a description of the database. |
| It can be considered as an extension of the database schema. | This can be considered as a blueprint of a database and gives a list of fields in database with their data types. |
| A database can have many states at different instance of time. | Database schema doesn’t change with time. |
(c) An organisation wants to create a database EMP DEPENDENT to maintain following details about its employees and their dependent. [3]
EMPLOYEE (AadharNumber, Name, Address, Department, EmployeelD)
DEPENDENT(EmployeeID, DependentName, Relationship)
(i) Name the attributes of EMPLOYEE, which can be used as candidate keys.
(ii) The company wants to retrieve details of dependent of a particular employee. Name the tables and the \text { key which are required to retrieve this detail. }
(iii) What is the degree of EMPLOYEE and DEPENDENT relation?
Answer:
(i) AadharNumber, EmployeelD.
(ii) EMPLOYEE and DEPENDENT tables and foreign key EmployeeID are required to retrieve this detail.
(iii) Degree of EMPLOYEE table is 5. Degree of DEPENDENT table is 3. [3]
(d) Define the generally used data types in SQL.
Answer:
Data type indicates the type of data value that an attribute can have. Commonly used data types are:
VARCHAR2 (SIZE): It is variable length characters string. It can hold 4000 bytes of characters.
CHAR (size): It specifies a fixed length characters string. Maximum size is 255.
VARCHAR(size): This data type is currently synonymous with VARCHAR2 datatype.
NUMERIC(P,S): It is used to store fixed or floating point numbers where P-Precision or total number of digits in range 1 to 38.
S-Scale or numbers of digits to right of decimal point.
LONG: It stores variable length character strings containing up to 2 Giga bytes.
DATE: It is used to store date information. Default format is YYYY-MM-DD [4]
Question 5.
(a) What are advantages of SQL?
OR
Write SQL query to list the employee whose employee number is 101 [1]
Answer:
(a) SQL has many advantages which makes it popular and highly demanded. some advantages are-
- IFaster Query Processing
- Standardized Language
- No Coding Skills 1
OR
SELECT * FROM Employee WHERE Emp_num = 101; [1]
(b) What do you mean by key?
Answer:
Key is a data item that allows to uniquely identify individual occurrences or an entity type. An entity types usually has an attribute whose values are distinct for each individual entity in the entity set. [2]
(c) How to select all records from the table?
Answer:
To select all the records from the table we need to use the following:
Syntax: SELECT * FROM table_name; [2]
(d) Write command to create table Emp whose fields are
| ID | int |
| Name | char |
| Salary | float |
| Address | varchar |
| Age | int |
| Phone | int |
Answer:
CREATE TABLE Emp
(ID int Primary Key,
Name Char (20),
Salary Float,
Address Varchar (30),
Age int,
Phone int); [2]
(e) Write SQL query for the questions that follow based on given table Worker: [4]
| Worker_ID | Name | Salary | Joining_Date | Department |
| 001 | Monika | 10000 | 2014-02-02 | HR |
| 002 | Shiksha | 8000 | 2014-06-11 | Admin |
| 003 | Arun | 30000 | 2014-02-20 | HR |
| 004 | Nishant | 15000 | 2014-12-20 | Admin |
| 005 | Vivek | 15000 | 2014-12-20 | Admin |
| 006 | Santosh | 20000 | 2014-01-20 | Accountant |
| 007 | Naresh | 7500 | 2014-04-11 | Accountant |
(i) To display Name, salary of all workers,
(ii) To display name of those workers whose salary is more than 15000.
(iii) To display all records.
(iv) To display records for those workers who are in HR department.
Answer:
(i) SELECT Name, Salary FROM Worker;
(ii) SELECT NAME FROM Worker WHERE Salary> 15000;
(iii) SELECT *FROM Worker;
(iv) SELECT * FROM Worker WHERE
Department = “HR”; [4]
(f) What is relational model? Also, define its terminology. [4]
Answer:
The relational model represents the database as a collection of relations. A relation is nothing but a table of values. Every row in the table represents a collection of related data values. These rows in the table denote a real-world entity or relationship.
The table name and column name are helpful to interpret the meaning of values in each row. The data are represented as a set of relations. In the relational model, data are stored as a table. However, the physical storage of the data is interdependent of the way the data are logically organized. Relational Model Terminology:
(i) Attribute: In a database management system (DBMS), an attribute refers to a database component such as a table columns. It also may refer to a database field. Attribute describes the instance in the row of database. E.g. Student, RollNo., Name, etc.
(ii) Relation: It is sometimes used to refer to a table in a relational database but is more commonly used to describe the relationships that can be created between those tables in a relational database. Relations have three important properties as name, cardinality and degree.
These are described as:
- Name: The first property of a relation is its name which is represented by the title or entity identifier.
- Cardinality: It refers to the number of rows (tuples) in relation that defines the uniqueness of data value contained in a column.
- Degree: It refers to the number of columns (attributes) in a relation.
(iii) Domain: It is defined as the set of all unique values permitted for an attribute. For example; a domain of dates is the set of all possible valid dates, a domain of integer is a set of all possible whole number;a domain of day of week is Monday, Tuesday. Sunday.
(iv) Tuples: Rows of relations are generally termed as tuples. [4]
Question 6.
(a) Out of the following, find those identifiers which cannot be used for naming variable or functions in a Python program :
Total *Tax, While, Class, Switch, 3rd Row, finally, CoIumn31, Total [2]
Answer:
(a) Total*Tax, 3rd Row, finally, While, Class [2]
Commonly Made Error:
Some students don’t learn the rules for naming the identifiers so they found difficulties in naming identifier.
Answering Tips:
Total*tax → Special characters are not used.
3rd Row → First character must be letter.
While, Class, finally → Key words are not allowed.
(b) Define the floor division (//) operator with an example. [2]
Answer:
Floor division operator is also used to divide first operand by second operand but it shows only whole part of the result and fractional part is truncated.
e.g. print (45.5 / / 5)
print(46//4)
print (23 / / 2)
Output
9.0
11
11 [2]
(c) Write output of the following code snippets,
list1, list2 = [123, ‘xyz’], [456, ‘abc’]
list1. extend (list2)
print “Extended list:”,list1
print list1. index (456)
list1. insert (3, ‘Hello’)
print list1
del list1 [2]
print list1 [3]
Answer:
Output
[123, ‘ ‘xyz’, 456, ‘ abc’ ]
2
[123, ‘xyz’, 456, ‘Hello’, ‘abc’ ]
[123, ‘xyz’, ‘Hello’, ‘abc’ ] [3]
(d) Write a program to input total number of sections and class teacher’s name in 11th class and display all information on the output screen. [3]
Answer:
classxi = dict ( )
n = input (“Enter total number of section in xiclass”)
i = 1
while i<=n:
a = raw_input (“enter section”)
b = raw_input (“enter class teacher name”)
classxi [a] = b
i – i + 1
print (“class”, “/t”, i, “section”, “/t”, “Teacher Name”)
for i in classxi :
print (“XI”, “/t”, i, “/t”, classxi [i])
Question 7.
(a) Define Augmented Reality. [2]
Answer:
(i) The superimposition of computer generated perceptual information over the existing physical surroundings is called as Augmented Reality.
(ii) The most important benefit of AR is that to the user it feels like a natural extension. AR only adds or hides data from the environment.
(b) What do you mean by robotics ? [2]
Answer:
(i) Robotics is the intersection of science, engineering and technology that produces machines called robots that substitute for human actions. Many aspects of robotics involve artificial intelligence; robots may be equipped with the equivalent of human senses such as vision, touch and the ability to sense temperature.
(ii) Robots are being used in industries, medical science, bionics, scientific research, military etc.
Case Based Questions (Attempt any 4]
Question 8.
Lists are the container which stores the heterogeneous elements of any type a integer character, floating point that store in square brackets [ ]. Consider following list for python language. [4]
L=[“Suresh”, 3.45, “Tree”, ’Amar’, [10,8.91, “Apple”], 456]
(i) The output of L[4][-2] will be:
(A) 10
(B) 8.91
(C) [10,8.91, ‘Apple’]
(D) 3.45
Answer:
(B) 8.91
(ii) The output of len(L[4]) is:
(A) 4
(B) Error
(C) 3
(D) None of these
Answer:
(C) 3
(iii) What will the statement L[2] = 234 do?
(A) It will replace the value (“Tree”) of the list.
(B) It cannot update the value and will generate error
(C) It will replace the value (3.45) of the list.
(D) None of these
Answer:
(A) It will replace the value (“Tree”) of the list.
(iv) print(len(L[0]+L[-l]) will print:
(A) Suresh456
(B) Suresh+456
(C) Error
(D) None of these
Answer:
(C) Error
(v) The output of print(L[l:5:3]) will be:
(A) [3.45, ‘Amar1, [10,8.91,’Apple’]]
(B) [3.45,’Amar’, 456]
(C) [3.45]
(D) [3.45,[10,8.91,’Apple’]]
Answer:
(D) [3.45,[10,8.91,’Apple’]]