CHAPTER 5

Choice Questions

 

1.   What is a program in computer science?

-  a) A set of machine language instructions

-  b) A collection of hardware components

-  c) An ordered set of instructions to be executed by a computer

-  d) A high-level language

-  Answer: c) An ordered set of instructions to be executed by a computer

2.   Which language is called machine language?

-  a) Python

- b) C++

-  c) Assembly

-  d) 0s and 1s

-  Answer: d) 0s and 1s

3.   What is source code?

-  a) Machine language code

-  b) High-level language code

-  c) Assembly language code

-  d) Hardware description

-  Answer: b) High-level language code

4.   Which of the following uses an interpreter?

- a) C++

-  b) Assembly

-  c) Python

-  d) Machine language

-  Answer: c) Python

5.   Which quote is attributed to Donald Knuth in the textbook?

-  a) “Programming is fun.”

-  b) “Computer programming is an art.”

-  c) “Machines are powerful.”

-  d) “High-level languages are easy.”

-  Answer: b) “Computer programming is an art.”

6.   Which of the following is NOT a feature of Python?

-  a) High-level language

-  b) Case-sensitive

-  c) Platform-dependent

-  d) Rich library of predefined functions

-  Answer: c) Platform-dependent

7.   What is the symbol for the Python prompt in interactive mode?

- a) $

- b) %

- c) &

- d) »>

-  Answer: d) »>

8.   What is the extension of Python source code files?

-  a) .java

-  b) .py

-  c) .exe

-  d) .txt

-  Answer: b) .py

9.   Which mode in Python allows the execution of individual statements instantaneously?

-  a) Script mode

-  b) Interactive mode

-  c) Batch mode

-  d) Compiled mode

-  Answer: b) Interactive mode

10.   Which of the following is a Python keyword?

-  a) print

-  b) import

-  c) function

-  d) main

-  Answer: b) import

11.  Which of the following is a valid identifier in Python?

-  a) 123abc

-  b) abc123

-  c) a!bc

-  d) None of these

-  Answer: b) abc123

12.   What is a variable in Python?

-  a) A reserved word

-  b) A function

-  c) An object uniquely identified by a name

-  d) A type of operator

-  Answer: c) An object uniquely identified by a name

13.   Which symbol is used for comments in Python?

- a) //

- b) #

**- c) @**

- d) &

-  Answer: b) #

14.   In Python, everything is treated as a(n):

-  a) Variable

-  b) Function

-  c) Object

-  d) Keyword

-  Answer: c) Object

15.   Which function returns the identity of an object in Python?

-  a) id()

-  b) identity()

-  c) object_id()

-  d) get_id()

-  Answer: a) id()

16.   What are the two execution modes in Python?

-  a) Compiled and Interpreted

-  b) Interactive and Script

-  c) Synchronous and Asynchronous

-  d) Batch and Real-time

-  Answer: b) Interactive and Script

17.   Which of the following is NOT a feature of Python?

-  a) Free and open-source

-  b) Case-sensitive

-  c) Platform-independent

-  d) Requires a compiler

-  Answer: d) Requires a compiler

18.   Which of the following is NOT a keyword in Python?

-  a) while

-  b) assert

-  c) print

-  d) pass

-  Answer: c) print

19.   What is the output of the following Python code: ‘print(“Hello, World!”)‘?

-  a) Hello, World!

-  b) “Hello, World!”

-  c) print(“Hello, World!”)

-  d) Syntax Error

-  Answer: a) Hello, World!

20.   Which of the following statements is true about Python?

-  a) Python is a low-level language.

-  b) Python is case-sensitive.

-  c) Python cannot be used for web development.

-  d) Python uses a compiler for execution.

-  Answer: b) Python is case-sensitive.

21.   What is the correct syntax for a single-line comment in Python?

-  a) // This is a comment

-  b) /* This is a comment */

-  c) # This is a comment

-  d) < This is a comment >

-  Answer: c) # This is a comment

22.   Which of the following is NOT a Python data type?

-  a) Integer

-  b) String

-  c) Boolean

-  d) Character

-  Answer: d) Character

23.   How do you create a variable in Python?

-  a) Using the var keyword

-  b) By simply assigning a value to it

-  c) Using the let keyword

-  d) By declaring it first

-  Answer: b) By simply assigning a value to it

24.   Which of the following is used for indentation in Python?

-  a) Curly braces

-  b) Parentheses

-  c) Tabs or spaces

-  d) Semicolons

-  Answer: c) Tabs or spaces

25.   What will be the output of the following code: ‘print(2 + 3 * 4)‘?

- a) 20

- b) 14

- c) 24

- d) 12

-  Answer: b) 14

26.   Which Python function is used to get input from the user?

-  a) input()

-  b) read()

-  c) scanf()

-  d) get_input()

-  Answer: a) input()

27.   What does the following Python code do: ‘name = input(“Enter your name:”)‘?

-  a) Prints “Enter your name:”

-  b) Assigns the string “Enter your name:” to the variable name

-  c) Prompts the user to enter their name and stores it in the variable name

-  d) Generates a syntax error

-  Answer: c) Prompts the user to enter their name and stores it in the variable name

28.   Which of the following is an invalid variable name in Python?

-  a) var1

-  b) _var

-  c) 1var

-  d) var_1

-  Answer: c) 1var

29.   What is the output of the following code: ‘print(10 / 3)‘?

- a) 3.3333333333333335

- b) 3

- c) 3.0

- d) 10

- Answer: a) 3.3333333333333335

30.   Which of the following is NOT an arithmetic operator in Python?

- a) +

- b) -

- c) *

- d) &&

-  Answer: d) &&

31.   What is the correct way to create a string in Python?

-  a) ‘string s = “Hello”‘

-  b) ‘s = ‘Hello’‘

-  c) ‘s = Hello‘

-  d) ‘string s = ‘Hello’‘

-  Answer: b) ‘s = ‘Hello’‘

32.   Which of the following methods can be used to convert a string to a list in Python?

-  a) list()

-  b) split()

-  c) convert()

-  d) str()

-  Answer: b) split()

33.   Which of the following is NOT a valid Python data type?

-  a) List

-  b) Tuple

-  c) Dictionary

-  d) Array

-  Answer: d) Array

34.   What is the output of the following code: ‘print(“Hello” + ” ” + “World”)‘?

-  a) Hello World

-  b) HelloWorld

-  c) “Hello World”

-  d) Hello + World

-  Answer: a) Hello World

35.   Which operator is used for exponentiation in Python?

- a) ^

- b) **

-  c) exp()

-  d) pow()

-  Answer: b)

36.   Which of the following is a mutable data type in Python?

-  a) String

-  b) Tuple

-  c) List

-  d) Integer

-  Answer: c) List

37.   What is the output of the following code: ‘print(2**3)‘?

- a) 5

- b) 6

- c) 8

- d) 9

-  Answer: c) 8

38.   Which function is used to read input from the user in Python 3.x?

-  a) input()

-  b) raw_input()

-  c) scan()

-  d) read()

-  Answer: a) input()

39.   Which of the following statements will create a tuple in Python?

- a) t = [1, 2, 3]

- b) t = {1, 2, 3}

- c) t = (1, 2, 3)

- d) t = 1, 2, 3

- Answer: c) t = (1, 2, 3)

40.   What is the output of the following code: ‘print(type([]))‘?

-  a) <class ‘tuple’>

-  b) <class ‘list’>

-  c) <class ‘set’>

-  d) <class ‘dict’>

-  Answer: b) <class ‘list’>

41.   Which of the following operators is used for string concatenation in Python?

- a) +

- b) &

- c) .

-  d) concat()

-  Answer: a) +

42.   What is the correct way to declare a variable in Python?

-  a) var x = 5

- b) x := 5

-  c) int x = 5

- d) x = 5

-  Answer: d) x = 5

43.   What will be the output of the following code: ‘print(10 % 3)‘?

- a) 1

- b) 3

- c) 10

- d) 0.3

-  Answer: a) 1

44.   Which method is used to remove an item from a list in Python by its value?

-  a) remove()

-  b) pop()

-  c) delete()

-  d) discard()

-  Answer: a) remove()

45.   What is the output of the following code: ‘print(5 == 5)‘?

-  a) True

-  b) False

-  c) Syntax Error

- d) 5

-  Answer: a) True

46.   Which method can be used to convert a list into a tuple in Python?

-  a) tuple()

-  b) list_to_tuple()

-  c) to_tuple()

-  d) convert()

-  Answer: a) tuple()

47.   Which of the following is used to define a block of code in Python?

-  a) Indentation

-  b) Curly braces

-  c) Parentheses

-  d) Square brackets

-  Answer: a) Indentation

48.   Which function is used to get the type of an object in Python?

-  a) type()

-  b) isinstance()

-  c) id()

-  d) obj_type()

-  Answer: a) type()

FILL-IN THE BLANK (SAMPLE).**

 

1.    Python is an example of a             -level programming language. (high)

2.    In Python, strings are enclosed in              or              . (single, double)

3.    Python’s core data types include             ,              , and             . (integers, floats, strings)

4.                  are used to document Python functions and modules. (docstrings)

5.    Python uses              to indicate a block of code. (indentation)

6.                  are objects in Python that cannot be changed after assignment. (tuples)

 

 

2   Marks Questions and Answers

 

1.    What is a programming language? A programming language is a language used to specify a set of instructions to a computer to carry out a specific task.

2.    Define a program. A program is an ordered set of instructions to be executed by a computer to carry out a specific task.

3.    What is machine language? Machine language, also known as low-level language, is the language of 0s and 1s that is directly understood by the computer.

4.    What is the difference between high-level language and machine language? High-level languages are easier for humans to write and understand, whereas machine language is composed of binary code (0s and 1s) and is directly understood by the computer.

5.    Name any two high-level programming languages. Python and Java.

6.    What is source code? Source code is a program written in a high-level language.

7.    What is the role of a compiler? A compiler translates the entire source code into machine language as a whole and generates error messages if any.

8.    What is the role of an interpreter? An interpreter processes program statements one by one, translating and executing them until an error is encountered or the program is successfully executed.

9.    Define Python as a high-level language. Python is a high-level, interpreted, and case-sensitive program- ming language known for its readability and simplicity.

10.    What does it mean that Python is an interpreted language? Python being an interpreted language means that its programs are executed by an interpreter, which processes each statement one by one.

11.    How does Python handle case sensitivity? Python is case-sensitive, meaning identifiers like NUMBER and number would be considered different.

12.    Mention any two features of Python. Python is portable and platform-independent, and it has a rich library of predefined functions.

13.    What is the extension of a Python script file? The extension of a Python script file is .py.

14.    Explain the interactive mode in Python. In interactive mode, individual statements can be executed instantaneously, and results are displayed immediately.

15.    What is script mode in Python? In script mode, a Python program is written in a file, saved, and then executed as a whole.

16.    What are Python keywords? Python keywords are reserved words that have specific meanings to the interpreter and cannot be used as identifiers.

17.    Define identifiers in Python. Identifiers are names used to identify variables, functions, or other entities in a program.

18.    What are variables in Python? Variables in Python are names that refer to objects stored in memory.

19.    How are comments added in Python? Comments in Python are added using the # symbol; everything following the # till the end of the line is treated as a comment.

20.    What is an object in Python? An object in Python is an instance of a data type that has a unique identity, attributes, and behavior.

21.    What is implicit conversion?  Implicit conversion is the automatic conversion of one data type to another by the interpreter.

22.    What is explicit conversion? Explicit conversion is the manual conversion of one data type to another using functions like int(), float(), str(), etc.

 

3   Marks Questions and Answers

 

1.    Explain the process of program execution in Python using an interpreter.

 

•    Python uses an interpreter to execute programs. The interpreter processes the program statements one by one, translating and executing each statement sequentially until an error is encountered or the entire program is executed. If an error occurs, execution stops. This contrasts with a compiler, which translates the entire source code into object code before execution .

2.    What is the significance of the Python prompt »>?

 

•    The »> prompt in Python indicates that the interpreter is ready to accept instructions. This prompt is displayed in the Python interactive mode, also known as the Python shell, where users can type commands or statements to be executed immediately .

3.    Describe the use of indentation in Python.

 

•    Indentation in Python is used to define the blocks of code. Unlike other programming languages that use braces or keywords, Python relies on indentation levels to group statements. Consistent indentation is crucial because it directly affects the program’s structure and execution .

4.    Explain the concept of ‘interactive mode’ with an example.

 

•    Interactive mode in Python allows users to type and execute Python commands directly at the »> prompt. This mode is useful for testing and debugging code snippets. For example:

>>> print("Hello, World!") Hello, World!

This command is executed immediately, and the result is displayed on the screen .

5.    What are the rules for naming an identifier in Python?

 

•    Identifiers in Python must follow these rules:

 

1.    Must start with a letter (a-z, A-Z) or an underscore (_).

2.    Can contain letters, digits (0-9), and underscores.

3.    Cannot start with a digit.

4.    Python keywords cannot be used as identifiers.

5.    Identifiers are case-sensitive .

 

6.    Explain with an example how variables are declared in Python.

 

•    Variables in Python are declared by assigning a value to a name. For example:

 

>>> x = 10

 

>>> name = "Alice"

 

Here, x is an integer variable with a value of 10, and name is a string variable with a value of “Alice” .

 

7.    How does Python handle data types?

 

•    Python handles data types dynamically, meaning variables do not need to be declared with a specific type. Python supports various data types, including integers, floats, strings, lists, tuples, dictionaries, and sets. The type of a variable is determined at runtime based on the value assigned to it .

8.    Describe the purpose of comments in a Python program.

 

•    Comments in Python are used to document the code and make it easier to understand. They are ignored by the interpreter and can be single-line comments starting with # or multi-line comments enclosed in triple quotes (’’’ or “““). Comments help explain the logic and purpose of the code, making it easier to maintain and collaborate with others .

9.    Explain the significance of the id() function in Python.

•    The id() function in Python returns the unique identity (memory address) of an object. This identity is guaranteed to be unique and constant for the object during its lifetime. The id() function is useful for understanding the object’s behavior and identity management in memory .

10.    Differentiate between None and False in Python keywords.

 

•    None is a special constant in Python representing the absence of a value or a null value. It is often used to signify that a variable has no value. False, on the other hand, is a Boolean value indicating the logical false. It is used in logical operations and comparisons. While None and False are distinct, both can be used in condition checks where None evaluates to False in a Boolean context .

11.    What is meant by ‘Python is platform-independent’?

 

•    Python is considered platform-independent because Python programs can run on various operating systems without modification. This is possible because Python code is interpreted, and the Python interpreter abstracts the underlying platform details. As long as the system has a compatible Python interpreter installed, the same Python code can run on Windows, macOS, Linux, and other platforms

.

 

12.    Describe how Python uses indentation for blocks and nested blocks.

 

•    In Python, indentation is used to define the scope of loops, functions, and other constructs. Con- sistent indentation levels indicate a block of code. For nested blocks, each new block is indented further, usually by four spaces. This indentation helps Python understand the grouping of statements, replacing the need for braces or keywords used in other languages .

13.    Explain the term ‘portable’ in the context of Python.

 

•    The term ‘portable’ in the context of Python refers to the ability to write Python code that can run on different operating systems and environments without requiring changes. Python achieves portability through its interpreter, which handles platform-specific details, allowing the same code to execute on any system with a compatible Python interpreter .

14.    What are Python libraries and why are they important?

 

•    Python libraries are collections of modules and packages that provide pre-written code to perform common tasks. They are important because they save developers time and effort by offering reusable code for various functionalities, such as data manipulation, web development, machine learning, and more. Popular Python libraries include NumPy, Pandas, Matplotlib, and TensorFlow .

15.    Describe how to download and install Python.

 

•    To download and install Python:

1.   Visit the official Python website (https://www.python.org/ ).

2.    Download the installer for your operating system.

3.    Run the installer and follow the on-screen instructions.

4.    Ensure that the option to add Python to the system PATH is selected.

5.   Verify the installation by opening a command prompt or terminal and typing python –version .

 

16.    What is meant by ‘Python is free and open source’?

 

•    Python being ‘free and open source’ means that it is freely available for anyone to use, modify, and distribute. The source code of Python is openly accessible, allowing developers to contribute to its development and customize it as needed. This openness fosters a large and active community that continually improves the language and its ecosystem .

 

5 Marks Questions and Answers

 

1.    Discuss the differences between a compiler and an interpreter.

 

•    Translation Unit: A compiler translates the entire source code into machine code at once, while an interpreter translates one statement at a time.

•    Execution Speed: Compiled programs generally run faster because the translation happens before execution. Interpreted programs run slower as each instruction is translated during execution.

•    Error Detection: Compilers detect errors in the entire program during the compilation stage, while interpreters detect errors line by line, making it easier to debug incrementally.

•    Intermediate Code: Compilers generate an intermediate object code that can be executed later, while interpreters do not produce an intermediate code.

•    Usage: Interpreters are often used for scripting and testing because of their immediate feedback, whereas compilers are used for production software due to their efficiency.

2.    Discuss the various features of Python that make it a preferred language for beginners.

 

•    Simplicity: Python’s syntax is clear and readable, making it easy to learn and write code.

•    Interpreted Language: Python’s interactive mode allows beginners to test code snippets and see results immediately, facilitating learning.

•    Extensive Libraries: Python has a rich set of libraries and frameworks that support various tasks such as web development, data analysis, and machine learning.

•    Community Support: Python has a large and active community that provides extensive resources, tutorials, and documentation, aiding beginners in learning.

•    Versatility: Python can be used for a wide range of applications, from simple scripting to complex web applications, making it a valuable skill for beginners.

3.    Explain the concept of ‘everything is an object’ in Python with examples.

•    Object-Oriented: In Python, every value is an object, and each object has a type, known as its class. This applies to numbers, strings, functions, classes, and even modules.

•    Integers as Objects: For example, when you create an integer a = 5, a is an object of type int.

•    Strings as Objects: Similarly, when you create a string s = “Hello”, s is an object of type str.

•    Functions as Objects: Functions in Python are objects too. For example, def func(): pass defines a function func which is an object of type function.

•    Modules as Objects: Modules are objects as well. When you import a module like import math, the math module is an object of type module.

4.    Explain the different data types available in Python with examples.

 

•    Integers: Whole numbers, e.g., x = 10.

•    Floats: Decimal numbers, e.g., y = 10.5.

•    Strings: Text data, enclosed in quotes, e.g., name = “Alice”.

•    Lists: Ordered collections of items, e.g., my_list = [1, 2, 3, “apple”].

•   Dictionaries:   Collections of key-value pairs, e.g., my_dict = {“key1”:   “value1”, “key2”: “value2”}.

•    Tuples: Immutable ordered collections, e.g., my_tuple = (1, 2, 3).

•    Sets: Unordered collections of unique items, e.g., my_set = {1, 2, 3}.

•    Booleans: True or False values, e.g., is_valid = True.

 

5.    Discuss the significance of Python in the context of modern programming and software develop- ment.

•    Versatility: Python’s ability to handle various domains such as web development, data science, artificial intelligence, and automation makes it highly versatile.

•    Productivity: Python’s simple syntax and readability contribute to faster development and reduced maintenance costs.

•    Community and Support: Python’s large community and extensive libraries provide robust sup- port and resources for developers.

•    Adoption in Industry: Many leading companies and organizations use Python for their develop- ment needs, enhancing its credibility and demand in the job market.

•    Educational Tool: Python’s simplicity and ease of learning make it an excellent language for teach- ing programming in schools and universities.

6.    Explain the use of comments in Python with examples and describe their importance.

•    Single-line Comments: Use the # symbol, e.g., # This is a comment.

•    Multi-line Comments: Use triple quotes, e.g., ’’’ This is a multi-line comment ’’’.

•    Documentation: Comments help in documenting the code, explaining what specific blocks or lines of code do.

•    Debugging: Comments can be used to temporarily disable code for debugging purposes.

•    Collaboration: Comments are essential for collaborative projects as they help team members un- derstand each other’s code.

7.    Describe the rules for naming identifiers in Python and explain why these rules are important.

 

•    Start with a Letter or Underscore: Identifiers must begin with a letter (a-z, A-Z) or an underscore (_).

•    Contain Letters, Digits, or Underscores: Subsequent characters can be letters, digits (0-9), or underscores.

•    Case-sensitive: Identifiers are case-sensitive, meaning Var and var are different.

•    No Keywords: Keywords cannot be used as identifiers, e.g., def, class, etc.

•    Meaningful Names: Using meaningful names makes the code more readable and maintainable.

•    Avoid Confusion: Following these rules prevents errors and makes the code easier to understand and maintain.

8.    Explain the concept of high-level and low-level programming languages and their differences.

 

•    High-level Languages: These languages are closer to human languages and abstract away most of the hardware details. Examples include Python, Java, and C++.

•    Low-level Languages: These languages are closer to machine code and provide little abstraction from the hardware. Examples include Assembly and Machine Code.

•    Ease of Use: High-level languages are easier to learn and use, while low-level languages require more detailed knowledge of the hardware.

•    Portability: High-level languages are generally more portable across different hardware platforms, whereas low-level languages are specific to a particular type of hardware.

•    Performance: Programs written in low-level languages can be more efficient and faster but are more complex to write and maintain compared to high-level languages.

9.    Discuss the use of Python in web development and provide examples of popular web services built with Python.

•    Frameworks: Python has powerful web frameworks like Django and Flask that simplify web de- velopment.

MOHAMMED

•    Backend Development: Python is widely used for server-side programming, handling requests, and connecting to databases.

•    APIs: Python is commonly used to develop RESTful APIs, facilitating communication between different parts of a web service.

•    Popular Web Services: Examples of popular web services built with Python include Instagram, Pinterest, and Dropbox.

•    Integration: Python can easily integrate with other technologies and services, making it a versatile choice for web development.

10.   

THEEN

Explain with examples the different types of operators available in Python.

 

•   

MA

Arithmetic Operators:  Used for mathematical operations, e.g., + (addition), - (subtraction), * (mul- tiplication), / (division).

•    Comparison Operators: Used to compare values, e.g., == (equal to), != (not equal to), > (greater than).

•    Logical Operators: Used to combine conditional statements, e.g., and, or, not.

•    Assignment Operators: Used to assign values to variables, e.g., =, +=, -=.

11.    Discuss the role of Python in education and why it is a good choice for learning programming.

 

•    Ease of Learning: Python’s simple and readable syntax makes it an excellent choice for beginners.

•    Versatility: Python can be used for various applications, from web development to data science, providing a broad learning experience.

•    Active Community: Python’s large and active community offers extensive resources, tutorials, and support for learners.

•    Immediate Feedback: Python’s interactive mode allows learners to test code snippets and receive immediate feedback, facilitating learning.

•    Real-world Applications: Learning Python provides practical skills that are in high demand in the job market, enhancing career prospects.

12.    Explain various types of Errors.

 

•    Syntax Errors: Errors in the structure of the code, such as missing colons, parentheses, or incorrect indentation.

•    Runtime Errors: Errors that occur during program execution, such as division by zero or accessing a variable that has not been defined.

•    Logical Errors: Errors in the logic of the code that produce incorrect results, even though the code runs without crashing.

EXERCISES (CHAPTER END QUESTIONS)

Question 1

Which of the following identifier names are invalid and why?

 

1.    Serial_no.

2.    1st_Room

3.    Hundred$

4.    total-Marks

5.    True

 

Answer:

 

•    Identifier name can’t contain dot.

•    1st_Room: Invalid because identifiers cannot start with a digit.

•    $ symbol is special character that can’t be part of an identifier name.

•    total-Marks: Invalid because identifiers cannot contain hyphens (-).

•    True: Invalid because True is a keyword in Python and cannot be used as an identifier.

 

Question 2

Write the corresponding Python assignment statements:

 

1.    Assign 10 to variable length and 20 to variable breadth.

2.    Assign the average of values of variables length and breadth to a variable sum.

3.    Assign a list containing strings ‘Paper’, ‘Gel Pen’, and ‘Eraser’ to a variable stationery.

 

4.    Assign the strings ‘Mohandas’, ‘Karamchand’, and ‘Gandhi’ to variables first, middle and last.

5.    Assign the concatenated value of string variables first, middle and last to variable fullname. Make sure to incorporate blank spaces appropriately between different parts of names.

Answer:

 

1.    length = 10

2.    sum = (length + breadth) / 2

3.   

R

THEEN

stationery = [‘Paper’, ‘Gel Pen’, ‘Eraser’]

4.   

first = ‘Mohandas’

5.    fullname = first + ’ ’ + middle + ’ ’ + last

 

Question 3

Write logical expressions corresponding to the following statements in Python and evaluate the expres- sions (assuming variables num1, num2, num3, first, middle, last are already having meaningful values):

1.    The sum of 20 and –10 is less than 12.

2.    num3 is not more than 24.

3.    6.75 is between the values of integers num1 and num2.

4.    The string ‘middle’ is larger than the string ‘first’ and smaller than the string ‘last’.

5.    List Stationery is empty.

 

Answer:

 

1. (20 + -10) < 12 # True

2. num3 <= 24

3. num1 <= 6.75 <=num2

4.    first < middle < last

5.    len(stationery) == 0

 

Question 4

Add a pair of parentheses to each expression so that it evaluates to True.

 

1. 0 == 1 == 2

2. 2 + 3 == 4 + 5 == 7

3. 1 < -1 == 3 > 4

 

Answer:

 

1. 0 == (1 == 2)

2. 2 + (3 == 4) + 5 == 7

3. (1 < -1) == (3 > 4)

 

THEEN

Question 5

Write the output of the following:

 

1.

 

num2 = num1 + 1 num1 = 2 print(num1, num2)

2.

 

num1, num2 = 2, 6

3.

 

Answer:

 

1. 2 5

2. 6 4

3. This code will result in an error because num3 is not defined.

 

Question 6

Which data type will be used to represent the following data values and why?

1.    Number of months in a year

2.    Resident of Delhi or not

3.    Mobile number

4.    Pocket money

5.    Volume of a sphere

6.    Perimeter of a square

7.    Name of the student

8.    Address of the student

 

Answer:

 

1.    int - The number of months is a whole number.

2.    bool - It is a binary state (True or False).

3.    str - Mobile numbers can contain leading zeros and are not used for calculations.

4.    float - Pocket money can have decimal values.

5.    float - Volume can be a decimal value.

6.    float - Perimeter can be a decimal value.

7.    str - Names are textual data.

8.    str - Addresses are textual data.

 

Question 7

Give the output of the following when num1 = 4, num2 = 3, num3 = 2:

 

1. += num2 + num3

2.    num1 = num1 ** (num2 + num3)

3.    num1 **= num2 + num3 4. num1 = ‘5’ + ‘5’ print(num1)

5. print(4.00 / (2.0 + 2.0))

6. num1 = 2 + 9 * ((3 * 12) - 8) / 10

print(num1)

 

7.

num1 = 24 // 4 // 2 print(num1)

R

8. num1 = float(10)

9. num1 = int(‘3.14’)

10. print(‘Bye’ == ‘BYE’)

11. print(10 != 9 and 20 >= 20)

12. print(10 + 6 * 2 ** 2 != 9 // 4 - 3 and 29 >= 29 / 9)

13. print(5 % 10 + 10 < 50 and 29 <= 29)

14. print((0 < 6) or (not(10 == 6) and (10 < 0)))

 

Answer:

 

1. 9

2. 1024

3. 1024

4. 55

5. 1.0

6. 27.2

7. 3

8. 10.0

9.    Error (cannot convert ‘3.14’ to an integer)

10.    False

11.   True

12.    True

13.    True

14.    True

Question 8

Categorise the following as syntax error, logical error or runtime error:

 

1. 25 / 0

2. num1 = 25; num2 = 0; num1/num2

 

Answer:

 

1.    Runtime error (division by zero)

2.    Runtime error (division by zero)

 

Question 9

A dartboard of radius 10 units and the wall it is hanging on are represented using a two-dimensional coordinate system, with the board’s center at coordinate (0,0). Variables x and y store the x-coordinate and the y-coordinate of a dart that hits the dartboard. Write a Python expression using variables x and y that evaluates to True if the dart hits (is within) the dartboard, and then evaluate the expression for these dart coordinates:

1. (0,0)

2. (10,10)

3. (6, 6)

4. (7,8)

 

Answer:

(x**2 + y**2) <= 100

 

1.    True (0,0 is at the center)

2.    False (10,10 is outside the dartboard)

3.    True (6,6 is within the dartboard)

4.    True (7,8 is within the dartboard)

 

Question 10

Write a Python program to convert temperature in degree Celsius to degree Fahrenheit. If water boils at 100 degree C and freezes at 0 degree C, use the program to find out what is the boiling point and freezing point of water on the Fahrenheit scale.

Answer:

 

boiling_point_C = 100

freezing_point_C = 0

#   Conversion   formula:   F   =   C   *   9/5   +   32 boiling_point_F = boiling_point_C * 9/5 + 32 freezing_point_F = freezing_point_C * 9/5 + 32 print(f"Boiling point of water: {boiling_point_F}°F")

print(f"Freezing point of water: {freezing_point_F}°F")

 

Output: Boiling point of water: 212.0°F Freezing point of water: 32.0°F Question 11

Write a Python program to calculate the amount payable if money has been lent on simple interest. Prin- cipal or money lent = P, Rate of interest = R% per annum and Time = T years. Then Simple Interest (SI)

= (P x R x T)/ 100. Amount payable = Principal + SI. P, R and T are given as input to the program. Answer:

P = float(input("Enter the principal amount: ")) R = float(input("Enter the rate of interest: ")) T = float(input("Enter the time in years: "))

SI = (P \* R \* T) / 100 amount\_payable = P + SI print(f"Simple Interest: {SI}")

print(f"Amount Payable: {amount\_payable}")

 

Question 12

Write a program to calculate in how many days a work will be completed by three persons A, B and C together. A, B, C take x days, y days and z days respectively to do the job alone. The formula to calculate the number of days if they work together is xyz/(xy + yz + xz) days where x, y, and z are given as input to the program.

Answer:

x = float(input("Enter the number of days A takes to complete the work: ")) y = float(input("Enter the number of days B takes to complete the work: ")) z = float(input("Enter the number of days C takes to complete the work: ")) total_days = (x * y * z) / (x * y + y * z + x * z)

print(f"The work will be completed in {total_days} days if A, B, and C work together.")

 

Question 13

Write a program to enter two integers and perform all arithmetic operations on them. Answer:

a = int(input("Enter the first integer: ")) b = int(input("Enter the second integer: ")) print(f"Addition: {a + b}")

print(f"Subtraction: {a - b}") print(f"Multiplication: {a * b}") print(f"Division: {a / b}") print(f"Modulus: {a % b}") print(f"Exponentiation: {a ** b}") print(f"Floor Division: {a // b}")

Question 14 Write a program to swap two numbers using a third variable. Answer:

a = int(input("Enter the first number: ")) b = int(input("Enter the second number: ")) temp = a

a = b

b = temp

print(f"After swapping: a = {a}, b = {b}")

Question 15

Write a program to swap two numbers without using a third variable. Answer:

a = int(input("Enter the first number: ")) b = int(input("Enter the second number: ")) a, b = b, a

print(f"After swapping: a = {a}, b = {b}")

Question 16

Write a program to repeat the string “GOOD MORNING” n times. Here ‘n’ is an integer entered by the user.

Answer:

n = int(input("Enter the number of times to repeat the string: ")) result = "GOOD MORNING " * n

print(result)

Question 17

Write a program to find average of three numbers. Answer:

num1 = float(input("Enter the first number: ")) num2 = float(input("Enter the second number: ")) num3 = float(input("Enter the third number: ")) average = (num1 + num2 + num3) / 3

print(f"The average of the three numbers is {average}")

Question 18

Write a Python program to find the volume of spheres with radius 7cm, 12cm, 16cm, respectively. Answer:

import math

# Input from the user for three spheres (assuming fixed number) radius1 = float(input("Enter the radius of sphere 1 in cm: ")) radius2 = float(input("Enter the radius of sphere 2 in cm: ")) radius3 = float(input("Enter the radius of sphere 3 in cm: ")) # Calculating and printing volumes for each sphere

volume1 = (4/3) * math.pi * radius1**3 volume2 = (4/3) * math.pi * radius2**3 volume3 = (4/3) * math.pi * radius3**3 # Printing the volumes

print(f"The volume of a sphere with radius {radius1} cm is {volume1} cubic cm") print(f"The volume of a sphere with radius {radius2} cm is {volume2} cubic cm") print(f"The volume of a sphere with radius {radius3} cm is {volume3} cubic cm")

 

Question 19

Write a program that asks the user to enter their name and age. Print a message addressed to the user that tells the user the year in which they will turn 100 years old.

Answer:

 

import datetime

name = input("Enter your name: ") age = int(input("Enter your age: "))

current_year = datetime.datetime.now().year year_turning_100 = current_year + (100 - age)

print(f"Hello, {name}! You will turn 100 years old in the year {year_turning_100}.")

 

Question 20

 

The formula E=mc² states that the equivalent energy (E) can be calculated as the mass (m) multiplied by the speed of light (c = about 3×1083 ×10^83×108 m/s) squared. Write a program that accepts the mass of an object and determines its energy.

Answer:

 

c = 3 * 10**8 # speed  of  light  in  m/s

mass = float(input("Enter the mass of the object in kg: ")) energy = mass * c**2

print(f"The energy equivalent of the mass is {energy} joules.")

 

Question 21

Presume that a ladder is put upright against a wall. Let variables length and angle store the length of the ladder and the angle that it forms with the ground as it leans against the wall. Write a Python program to compute the height reached by the ladder on the wall for the following values of length and angle:

1.    16 feet and 75 degrees

2.    20 feet and 0 degrees

3.    24 feet and 45 degrees

4.    24 feet and 80 degrees

 

Answer:

 

#import the  math  module,  to  use  sin  &  radians  function

import math

length = int(input("Enter the length of the ladder: ")) degrees = int(input("Enter the alignment degree: ")) #Converting degrees to radian

radian = math.radians(degrees)

#Computing sin  value

sin = math.sin(radian)

# Calculating height and rounding it off to 2 decimal places

height = round(length * sin,2)

#displaying the  output

print("The height reached by ladder with length",length,"feet and aligned

↪        at",degrees,"degrees is",height, "feet.")

 

Important Questions

 

1.    Mention the features of Python programming language.

2.    Mention the two modes of execution in Python IDLE.

3.    What is Keyword? Mention some of the keywords in Python.

4.    What is Identifier? Mention the rules for naming an Identifier in Python?

5.    Explain the statement: “Everything is an Object in Python”.

6.    Mention the names of various data types in Python.

7.    Menton the names of the two sequence data types in Python?

8.    Distinguish between Mutable and immutable data types. Give a suitable example.

9.    What is Operator? Explain different types of operators in Python.

10.    What is an Expression?

11.   What is type conversion? Explain two types of type conversion with suitable examples.

12.    What is Debugging? Explain various types of Errors.