Students must start practicing the questions from CBSE Sample Papers for Class 11 Computer Science with Solutions Set 1 are designed as per the revised syllabus.
CBSE Sample Papers for Class 11 Computer Science Set 1 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) _________ software are made to perform specific task. [1]
(A) System
(B) Application
(C) Utility
(D) None of these
OR
Which of the following boolean operator operate on single input?
(A) NOT
(B) AND
(C) OR
(D) NAND
Answer:
(a) Option (B) is correct.
Explanation:
An application software is designed of fulfil the specific needs of the uses.
OR
Option (A) is correct.
Explanation:
AND .OR, NAND all take more than one input.
(b) Character Data type values should be delimited by using the single quote (True/False)? [1]
Answer:
True
(c) What is displayed when we print an empty string? [1]
(A) 0
(B) 1
(C) Name of the string
(D) Blank space
Answer:
Option (D) is correct.
Explanation:
Python string is called an empty string if the string doesn’t have any character, white space whatsoever.
(d) Right index starts from: [1]
(A) 0
(B) 1
(C) -1
(D) None of these
Answer:
Option (C) is correct
Explanation:
Python supports two types of Index i.e., Positive, and Negative indexes. Positive index starts from 0 as (left to right) and Negative index start from -1 as (right to left).
(e) Python executes the set of instructions following statement as normal program. [1]
(A) try
(B) raise
(C) except
(D) else
Answer:
Option (A) is correct.
(f) Write the value justification: [1]
(i) 2* *(3+4)
(ii) 2*3+4
Answer:
(i) 14
(ii) 10
Commonly Made Error
Students mostly prefer right to left evaluation. But evaluation must be from left to right depending on \ operator precedence.
Answering Tip
Always remember that the value given in the parenthesis () must be evaluated first as () has higher precedence followed by * which is next highest followed by +
(g) What is spyware? How long is their period of activity? [2]
Answer:
Spyware is software that spies on the activities of a computer and reports it to the people who pay for such data. These remain active unless someone switches them off or removes them properly.
(h) Read the following text and answer the following questions on the basis of the same: [5]
A computer is a programmable machine. The two principal characteristics of a computer are: It responds to a specific set of instructions in a well-defined manner, and it can execute a prerecorded list of instructions (a program). Modern computers are electronic and digital. The actual machinery wires, transistors, and circuits are called hardware; the instructions and data are called software.
1. Which of the following is the correct definition of Computer?
(A) Computer is a machine or device that can be programmed to perform arithmetical or logic operation sequences automatically.
(B) Computer understands only binary language which is written in the form of Os & Is.
(C) Computer is a programmable electronic device that stores, retrieves, and processes the data.
(D) All of the mentioned.
Answer:
Option (D) is correct.
Explanation:
A computer is a machine or device that can be programmed to perform arithmetical or logic operation sequences automatically. The computer understands only binary codes (Os & Is).
2. Which of the following is the brain of the computer?
(A) Central Processing Unit
(B) Memory
(C) Arithmetic and Logic unit
(D) Control unit
Answer:
Option (A) is correct.
Explanation:
The CPU is referred to as the brain of a computer. It consists of a control unit and an arithmetic and logic unit. It is responsible for performing all the processes and operations.
3. Which of the following is not a characteristic of a computer?
(A) Versatility
(B) Accuracy
(C) Diligence
(D) I.Q.
Answer:
Option (D) is correct.
Explanation:
The Computer system has no I.Q. of its own. It does only what it is programmed to do. It cannot take decisions of its own.
A computer is diligent because it can work continuously for hours without getting any errors or without getting grumbled.
The accuracy of a computer is consistently high and its level of accuracy depends on its design. A computer can perform any task if, it can be broken down into a series of logical steps. Therefore, a computer is versatile.
4. Which of the following unit is responsible for converting the data received from the user into a computer understandable format?
(A) Output Unit
(B) Input Unit
(C) Memory Unit
(D) Arithmetic & Logic Unit
Answer:
Option (B) is correct
Explanation:
The Input Unit converts the data, which the user enters into a language that the computer understands, i.e. it converts the data into binary format.
5. Which of the following is designed to control the operations of a computer?
(A) User
(B) Application Software
(C) System Software
(D) Utility Software
Answer:
Option (C) is correct
Explanation:
Software is basically classified into two: System and application. System Software is designed to control the operations and extend the processing capability ol a computer system.
Question 2.
(a) Python is case sensitive. (TRUE/ FALSE) [1]
Answer:
True
(b) _________ is the simplest form of decision statement. [1]
Answer:
if
(c) What is the need of debugger tool? [2]
Answer:
Debugger tools are very useful. If the code is big or the error is not clear, it shows line by line execution and its result on variable interactively. This helps the programmer to get to the root of the problem.
(d) Karan was reading an article on computer hardware in the Digit magazine. He came across a word ‘port. Help him to understand what a port is and what are its types. [2]
Answer:
A port is a connection point or interface between a computer and internal or external devices. Some common types of ports are:
- Serial Port
- Parallel Port
- USB Port
- PS/2 Port
- Infrared Port
- Firewire Port
(e) Write a program to accept a number from the user and test whether it is negative, positive or zero. Display appropriate message in each case. [4]
OR
Explain the logical errors with an example.
Answer:
n=float (input ( ‘Enter a number if(n<0) :
print(‘The number entered is negative’)
elif(n>0):
print(‘The number entered is positive’)
else:
print(‘The number entered is zero’)
OR
A logical error is a mistake in a program’s source code that results in incorrect or unexpected behaviour. It may simply produce the wrong output or may cause a program to crash while running.
Some commonly made logical errors are:
(i) Using the wrong variable name.
(ii) Indenting a block to the wrong level.
(iii) Getting operator precedence wrong.
(iv) Making a mistake in a boolean expression,
e.g. x = 2
y = 4 z = x*y/2
print (“Average:”, z)
Output Average: 4
Above code produces the output 4 but expected output is 3. This code is syntactically correct but logically wrong.
The error is that the formula to find the average of the numbers is incorrect.
Correct formula is—
avg = \(\frac{X+Y}{2}\)
Question 3.
(a) Tishya in her computer class learned about lists, but she was not able to understand clearly What a nested list is. Explain her the concept of nested lists. [1]
Answer:
When a list appears as an element of another list it is called a nested list.
(b) Explain RAM. [2]
Answer:
Computer RAM is the best known form of memory in our computer. Every file or application opened is placed in RAM. Any information the computer needs or uses becomes part of a continuous cycle where the CPU requests the data from RAM, processes it and then writes new data back to the RAM. This can happen millions of times a second. However, this is just for temporary file storage, so it is deleted when the files or applications are closed.
(c) What is the significance of a firewall in a computer security schemes. [2]
Answer:
An Internet firewall is a device or software that is designed to protect your computer from data and viruses that you do not want and keep out malevolent hackers and people who intend to do damage.
Question 4.
(a) Errors detected during execution are called _________ [1]
Answer:
Exception
(b) State the importance of sorting a list. [2]
Answer:
By sorting a list, searching information in the list can be optimized to a very high level. It also makes the data more readable. The lists can be sorted in ascending or descending order.
(c) Write a program to remove an element ’25’ from the given Tuple.
tuple1 = (5,10,15,20,25, 30) [4]
Answer:
tuplel = (5, 10, 15, 20, 25, 30)
list1= list(tuple1)
list1.remove(25)
tuple1=tuple(list1)
print(tuple1)
Question 5.
(a) Draw a flowchart to find the sum of first ‘n’odd numbers. Accept ‘n’ from the user. [3]
Answer:
Commonly Made Error
Students must make use of accurate symbol and shape based on the actions
Answering Tip
A student must remember that the Sum of first 10 odd numbers is n2 i.e is 102=100. Based on this the flow chart should be drawn.
(b) Tuples are an important feature of Python. State some features of Tuples. [3]
Answer:
Some features of tuples are:
- Elements cannot be added to tuple.
- Tuples can store duplicate value.
- For a given index number, the element accessed is always the same.
Question 6.
(a) Python is a free and open source language. What do you understand by this feature? [2]
Answer:
Free – No need to pay to download the software.
Open-source – Its source code is available, which can be modified/improved.
(b) Write a code that prints your full name and your Birthday as separate strings. [2]
Answer:
name = input (‘Enter name:’) bday = input(‘Enter birthday:’) print (‘Name:’, name) print (‘Birthday:’, bday)
(c) Write a program to accept a number from the user and print the table of that number. [4]
Answer:
x = int (input (‘Enter the number for which table is to be printed:’))
i = 1
while (i <= 10):
print (x, ‘*’, i, ‘=’, x*i)
i + = 1
Question 7.
(a) We should use strong and unique _________. [1]
Answer:
Password
(b) How does eavesdropping lead a victim to prove personal information? [4]
OR
How to Prevent Leaving Digital Footprints?
Answer:
Eavesdropping activities do not affect normal operation of transmission and communication. Therefore,
both the sender as well as the recipient are unaware of it. If there is any security break in communication such as an email not being encrypted or without a digital signature, it can easily be intercepted. Now the attacker defaces the normal email and receives the recipient’s personal or sensitive information. This type of interception is also known as Man-in-the Middle-attack.
OR
(a) Limit the amount of data you share willingly.
(b) Increase your privacy setting.
(c) Avoid untrustworthy websites.
(d) Keep your logins separate.
Question 8.
(a) Anuj wrote following code. How many times is the word “Welcome” printed in the following code?
t = “i love python”
for ch in t[2:7]:
print (“Welcome”) [2]
Answer:
5 times
(b) What are looping constructs? When does a loop terminate? [2]
Answer:
Looping statements are the set of statements that are executed more than once and is based on testing of
a condition. Till the time the condition remains True, the loop will be executed again and again. The loop terminates when the condition becomes false.
(c) Anubhav spends too much time on internet. Explain him some side effects of spending too much time on computers? [5]
Answer:
- The Internet can be addictive.
- Can have a negative impact on our physical and psychological well being.
- Muscle and joint problems.
- Overuse causes injuries like swelling, pain, joint stiffness, weakness and numbness.
- Eyestrain.
Question 9.
(a) Why is else statement used in a loop?
Answer:
Some looping statements contain an else statement. This else statement is optional. The set of statements following the else statement are executed, only when the loop is not terminated by a break statement.
(b) Write a program to print the following pattern:
12345
1234
123
12
1
Answer:
p=5 while p>=1: q= 1 while q<=p: print(q, end=' ') q=q+1 print () p=p-1
Question 10.
Technology has changed our world. What is technology ?
Answer:
It is the reflection of people’s imagination on solving existing problem.