CBSE Sample Papers for Class 11 Computer Science Set 9 with Solutions

Students must start practicing the questions from CBSE Sample Papers for Class 11 Computer Science with Solutions Set 9 are designed as per the revised syllabus.

CBSE Sample Papers for Class 11 Computer Science Set 9 with Solutions

Time Allowed: 3 hours
Maximum Marks: 70

General Instructions:

All questions are compulsory.
Attempt all parts of each question
Internal choices are given, choose any one of them.

Question 1.
(a) The hexadecimal equivalent of 1010 is ………………….. [1]
(A) 10₁₆
(B) 1000₁₆
(C) A₁₆
(D) F₁₆
Answer:
(A) 10₁₆

(b) A string may be specified by placing the characters within double quotes only. (True/False). [1]
Answer:
False

Explanation:
Empty dictionary is represented by { }

(d) The ………………………. method adds a single item at the end of an existing list [1]
(A) append ()
(B) extend ()
(C) insert ()
(D) update ()
Answer:
(A) append ()

Explanation:
append () is the function of list. It is used to add a single item at the end of list.

(e) None is one of the operators in python. [1]
Answer:
False

(f) What are jump statements? Explain their types. [2]
Answer:
Jump statements are used to take the control of the program out of the loop even if the test condition is still true.
Types of jump statements:
1. Break statement: It is used to stop execution of the loop immediately and transfer the flow of control to the statement immediately after the loop.
Syntax: break

2. Continue statement: It is used to stop execution of the loop immediately and transfer the flow of control to the beginning of the loop again.
Syntax: continue

(g) What is the importance of digital footprint? [2]
Answer:
Digital footprint stays forever and cannot be undone. College/ universities and employers look back at them to know about applicants. They try to figure out how they conduct themselves in real life before appointing them.

(h) Conditional Statement in Python performs different computations or actions depending on whether a specific Boolean constraint evaluates to True or False. Conditional statements are handled by if statements in Python. [5]
if, if-else, if-elif-else, switch etc., are some conditional statements used in Python.
1. Which one of the following is a valid Python if statement:
(A) if a >= 2:
(B) if(a >= 2)
(C) if (a = > 22)
(D) if a > = 22
Answer:
(A) if a >= 2:

Explanation:
if statement is used to decide whether a certain statement or block of statements will be executed or not i.e if a certain condition is true then a block of statement is executed otherwise not.

2. Which of following is not a decision-making statement?
(A) if-elif statement
(B) for statement
(C) if -else statement
(D) if statement
Answer:
(B) for statement

Explanation:
Decision-making statements in programming languages decide the direction of the flow of program execution.

3. What keyword would you use to add an alternative condition to an if statement?
(A) else if
(B) elseif
(C) elif
(D) None of the above
Answer:
(C) elif

Explanation:
elif is used to add an alternative condition to an if statement

4. In a Python program, a control structure:
(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.

5. Which statement will check if a is equal to b?
(A) ifa = b:
(B) if a == b:
(C) if a = = = c:
(D) if a == b
Answer:
(B) if a == b:

Explanation:
if a == b: statement will check if a is equal to b.

Question 2.
(a) Who developed Python Programming Language? [1]
Answer:
Guido Van Rossum in 1990 developed Python programming language.

(b) The equal to condition is written by using the = = operator. (True/False) [1]
Answer:
True

(c) (i) How can you convert a string to integer and when can it be used? [1]
(ii) What is the type of the following result: [1]
1+2.0+3
Answer:
(i) int(“string value”).
To convert numbers read from keyboard the following syntax is used.
(ii) float

(d) Ansh wrote following Python code to print each character of a string and also each character generated by the range function, but it contains some errors. Rewrite the following code after removing all syntax error(s). Underline each correction done in the code. [2]
STRING = “WELCOME”
NOTE “”
for s in range [0, 8]:
print (STRING[s] )
print s STRING
Answer:

STRING = "WELCOME"
NOTE = ""
for s in range (0,8):
print (STRING[s] )
print(s, STRING)

(e) (i) What is the use of flowcharts? [1]
(ii) In which direction does the control flow in case of a flow chart? [1]
(iii) How many conditional statements can be nested inside one another? [1]
(iv) What are the permissible values for the range function in for loop? [1]
Answer:
(i) Flowcharts are used to show the flow of program. This helps to analyze, design, document and manage a program.
(ii) Top to bottom.
(iii) Infinite number of statements.
(iv) The values for range function can either be list or string or tuples.

Question 3.
(a) How will you import select objects from a module? Give syntax. [1]
Answer:
From module import < Object name>, <object name>, …………… .

(b) What do you think is the need of a module in programming? [1]
Answer:
Modularity:
(i) Reduces the complexity of the program.
(ii) It creates a number of well-defined documented boundaries with the program.

(c) (i) What according to you might be the reason that every time you browse the net you get to see advertisements of same type? How can we stop this? [2]
(ii) List two ways in which stalkers trouble their victims. [2]
Answer:
(i) The advertisements that we see on websites are based on our browsing history. Deleting all previous history and cookies stored can stop websites from posting such advertisements.

(ii) 1. Stalkers collect personal information of the victim and post it on only filthy / obscene or illegal website as if the victim himself is posting the information.
2. Some stalkers subscribe the email account of the victim to imnumerable obscene or illegal sites.

Question 4.
(a) Only tuples can be added to tuples.(True/False). [1]
Answer:
True

(b) Differentiate between runtime error and compile time error. [2]
Answer:

DRAM	SRAM
(i) A DRAM cell consists of only one transistor and one capacitor.	A SRAM consists of internal flip-flops.
(ii) It has a large number of cells packed within the chip.	The number of cells on a SRAM chip is less.
(iii) It needs to be refreshed (about thousand times in a second) to retain the stored data.	It retains data as long as the power is supplied to it i.e. there is no need to refresh it.
(iv) DRAMs are used in primary storage sections of most computers.	SRAMs are used in specialized applications.

(c) Write a Python program to add two numbers. [4]
OR
Write a short note on literals in Python.
Answer:
a = input(‘Enter the value of a: ‘)
b = input(‘Enter the value of b: ‘)
sum = float(a) + float(b) # Add two numbers
print(‘The sum of {5} and {6} is {11}’.format(a, b, sum))

Literals are data items that have a fixed value. Python has following 5 literals.
1. String Literals: The text enclosed in quotes (single or double) is considered to be a string literal. e.g. ‘hello’, ‘d’, “hello”,”D”,’go123′, “siddh’s”. A string literal in Python can also include nongraphic characters such as Backslash(\), carriage return(cr), horizontal tab etc. The string literals can be single line or multiline.
A single line string ends in one line.
A multiline strings extend beyond one line to multiple lines. It can be created either by adding a backslash at the end of every line or by typing the text in triple quotes.

2. Numeric literals: These can be of any of the following three numerical types.

Int: These are positive or negative whole numbers. An integer without a sign is considered to be positive.
Float: These are floating point real values with decimal point between the integer and fractional parts.
(Complex: These are used to store complex numbers of the form a+bj where a and b are float values and j represents (-1)1/2

3. Boolean literals: It represents one of the two Boolean values i.e. True or False.

4. Special literal: None It is a special literal that indicates absence of a value and is generally used to indicate end of lists in python. It means that there is no useful information.

5. Literal Collections: In Python have literal collections like list, tuple, dictionary and set.

Question 5.
(a) Draw a flowchart to print numbers from n to 1. Where n is input by user. [3]
Answer:

Commonly Made Error:
A student must not forget to decrement the n value.

Answering Tip:
To print Number from n to 1 input n value. Decrement n value by 1 and if n<1 print the value on screen.

(b) What type of services are provided by the OS? What are the different categories of OS functions?
OR
Differentiate between GUI and CUI
Answer:
The services provided by OS to programs and users are:

Program Execution: The OS is responsible for executing various user and system programs.
Handling I/O operations: OS handles all types of inputs and outputs according to the device being used.
Manipulation of file system: This task involves the making of decisions regarding the storage of files.
Error detection and handling: OS is responsible for detecting and handling any error that occur
Resource Allocation – OS is responsible for making proper use of available resources.
Accounting – OS keeps an account of what type of functioning is taking place and what types of errors have occurred.
Information and Resource Protection: OS ensures the correct usage of available information and resources.

OS function can be categorized as follows:

Essential functions ensure effective utilization of computer system resources.
Monitoring functions monitor and collect information related to system performance.
Service functions enhance facilities provided to user.

Character User Interface (CUI)	Graphical User Interface (GUI)
The user interacts with the computer using commands like text.	The user interacts with the system using Graphics like icons, images.
Navigation is not easy.	Navigation is easy to use.
Usage is easy to use.	Usage is difficult, requires expertise.
It has a low memory requirement.	It has a high memory requirement.
Users interact with the computer system by typing commands into the keyboard.	Users interact with the computer system using a graphical interface, which includes menus and mouse clicks.
Users interact with the computer system using a graphical interface, which includes menus and mouse clicks.	It has a highly flexible user interface.

Question 6.
(a) Give an example for semantic error. [2]
Answer:
x = 10
y = 5
x – y = a
print (“value of a:”, a)
Output
Syntax Error: can’t assign to operator.
In the above code, the statement x – y = a will result in a semantic error as an expression cannot come on the left side of an assignment operator.
The correct statement is a = x – y

(b) (i) Write full form of IDLE. [1]
(ii) Whether Python is case sensitive or not. (Yes/No) [1]
Answer:
(i) Interactive Development and Learning Environment
(ii) Yes

x = int(input ("Enter the value of x:")
y = int(input ("Enter the value of y:")
if y > x:
print("y is greater than x")
elif x == y:
print("x and y are equal")
else:
print("x is greater than y")

Question 7.
(a) ……………………. is an unwanted soitware that infects our computer and makes it behave in the most unexpected manner. [1]
Answer:
Malware

(b) (i) Explain the term trademark [2]
(ii) What is Licensing?
OR
WRITE SOME e-mail Etiquettes.
Answer:
(i) It include any symbols, word, name, design, slogan, label, etc., that distinguishes the brands or commercial enterprises, from other brands or commercial enterprises. For example, no company other than ABC can use the ABC brand to sell shoes or clothes. It also prevents others from using a confusingly similar mark, including works or phrases.

(ii) A licensing system is used to transparently relay decryption keys to the ‘Reader’ application and these keys are locked in authorized devices. It is vital that decryption keys are not exposed to users (i.e., passwords) and are locked in devices (so they will not work on other devices) otherwise they could be given to other users along with the protected content.

(i) Write a clear concise subject line that reflects the body of the e-mail. Avoid subject lines with general works like, “Hi”, “Hello”and do not leave the subject line blank.
(ii) Always use an appropriate greeting. Begin youre-mail with phrases such as Good Morning, Good Afternoon etc. Be aware that funny sayings or colloquialisms may be completely misconstrued by your colleagues in overseas offices.
(iii) Always state if your e-mail needs are action and by when. Open-ended e-mails can be confusing. Having an further action is required is helpful.
(iv) Don’t hit reply all. It can be annoying to be copied into to every e-mail or to see every response in a chain if it is not relevant to your recipient.
(v) Never use inappropriate language in a e-mail. The reality is that your e-mail will remain on the server long after you have deleted it.

Question 8.
(a) Students these days are using technology excessively. This worries Ms Uma who is an educationist. List two ways in which excessive use of technology is affecting the students. [2]
Answer:
(i) Impact on eyes: This is the most common form of health hazard as prolonged hours of screen time can lead to extreme strain on the eyes.
(ii) Sleep problem: Bright light from computer devices block a hormone called melatonin which helps us sleep. Thus we can experience sleep disorders leading to short sleep cycles.

(b) Siddhant is a class IX student and he has started to learn details about the basic computer hardware. His elder brother is trying to explain him parts of a CPU. can you do this for him? [3]
Answer:
CPU (Central Processing Unit) is the brain of the computer. Its subcomponents are:
1. ALU: ALU or Arithmetic Logic Unit is responsible for performing all the four arithmetic operations (+, -, * , /) and some logical operations AND, OR, NOT. The data to be operated is brought from memory to ALU and the result is put back in the memory.

2. CU: CU or the control unit guides and controls the operations taking place; interpretation, flow and manipulation of all data and information. It executes all the instructions stored in the program. It also controls the flow of data from input devices to memory and from memory to output devices.

3. Registers: Registers are small units of data holding places. These are used by the CPU for temporarily holding important information during the time the processing is taking place.

(c) Arnav is a computer student, he is teaching his grandmother how to use a computer. Today he will be teaching her what a software is and what are its type, help him by answering the above two questions. [2]
Answer:
Software is a set of programs that controls the operation of a computer system and utilizes hardware. Software are of two types:

System Software
Application Software.

Question 9.
(a) (i) What is the meaning of the term Cyberculture?
(ii) What is the importance of new technology ?
Answer:
(i) Cyberculture is the term coined to mean the set of material and intellectual techniques, practices, attitude ways of thinking and values that are expressed and developed in cyberspace.
(ii) New technology improves quality of life for human beings.

(b) Write the output of these codes:
(i) for m in range (3) :
for n in range (2):
print (m, n, m * n)
Answer:
0 0 0
0 1 0
1 0 0
1 1 1
2 0 0
2 1 2

(ii) m = 10
n = 15
for j in range (m * 4 – n * 2):
print (j, end = ” “)
Answer:
0 1 2 3 4 5 6 7 8 9