Question 1

Question 1What are data types in Python? How are they important?

Accepted Answer

Data types are used to identify the type of data a memory location can hold and the associated operations of handling it. The data that we deal with in our programs can be of many types like character, integer, real number, string, boolean, etc. hence programming languages including Python provide ways and facilities to handle all these different types of data through data types. The data types define the capabilities to handle a specific type of data such as memory space it allocates to hold a certain type of data and the range of values supported for a given data type, etc.

Question 2

Question 5How many string types does Python support? How are they different from one another?

Accepted Answer

Python supports two types of strings — Single-line strings and Multi-line strings. Single line strings are enclosed in single or double quotes and terminate in one line. Multi-line strings store multiple lines of text and are enclosed in triple quotes.

Question 3

Question 10Are these values equal? Why/why not?20 and 20.020 and int(20)str(20) and str(20.0)'a' and "a"

Accepted Answer

The type of 20 is int whereas the type of 20.0 is float so they are two different objects. Both have the same value of 20. So, as values are same equality (==) operator return True but as objects are different is operator returns False.The value and type of both 20 and int(20) are the same and both point to the same object so both equality (==) and is operator returns True.For str(20) and str(20.0), both equality (==) and is operator returns False as their values are different and they point to two different objects.For 'a' and "a", both equality (==) and is operator returns True as their values are same and they point to the same object.

Question 4

Question 12What is the difference between implicit type conversion and explicit type conversion?

Accepted Answer

Implicit Type ConversionExplicit Type ConversionAn implicit type conversion is automatically performed by the compiler when differing data types are intermixed in an expression.An explicit type conversion is user-defined conversion that forces an expression to be of specific type.An implicit type conversion is performed without programmer's intervention.An explicit type conversion is specified explicitly by the programmer.Example:a, b = 5, 25.5c = a + bExample:a, b = 5, 25.5c = int(a + b)

Question 5

Question 14Given str1 = "Hello", what will be the values of:(a) str1[0](b) str1[1](c) str1[-5](d) str1[-4](e) str1[5]

Accepted Answer

(a) H(b) e(c) H(d) e(e) IndexError: string index out of rangeExplanationH0−5e1−4l2−3l3−2o4−1\begin{matrix} \underset{-5}{\overset{0}{\bold{H}}} & \underset{-4}{\overset{1}{\bold{e}}} & \underset{-3}{\overset{2}{\bold{l}}} & \underset{-2}{\overset{3}{\bold{l}}} & \underset{-1}{\overset{4}{\bold{o}}} \end{matrix}−5H0​​−4e1​​−3l2​​−2l3​​−1o4​​

Question 6

Question 19Given three Boolean variables a, b, c as : a = False, b = True, c = False. Evaluate the following Boolean expressions:(a) b and c(b) b or c(c) not a and b(d) (a and b) or not c(e) not b and not (a or c)(f) not ((not b or not a) and c) or a

Accepted Answer

(a) b and c     ⇒ False and True     ⇒ False(b) b or c     ⇒ True or False     ⇒ True(c) not a and b     ⇒ not False and True     ⇒ True and True     ⇒ True(d) (a and b) or not c     ⇒ (False and True) or not False     ⇒ False or not False     ⇒ False or True     ⇒ True(e) not b and not (a or c)     ⇒ not True and not (False or False)     ⇒ not True and not False     ⇒ False and True     ⇒ False(f) not ((not b or not a) and c) or a     ⇒ not ((not True or not False) and False) or False     ⇒ not ((False or True) and False) or False     ⇒ not (True and False) or False     ⇒ not False or False     ⇒ True or False     ⇒ True

Question 7

Question 21Write following expressions in Python:(a) 13b2h\dfrac{1}{3} b^2 h31​b2h

Accepted Answer

1 / 3 * b * b * h(b) πr2h\pi r^2 hπr2hAnswermath.pi * r * r * h(c) 13πr2h\dfrac{1}{3} \pi r^2 h31​πr2hAnswer1 / 3 * math.pi * r * r * h(d) (x2−x1)2+(y2−y1)2\sqrt{(x2 - x1)^2 + (y2 - y1)^2}(x2−x1)2+(y2−y1)2​Answermath.sqrt((x2 - x1) ** 2 + (y2 - y1) ** 2)(e) (x−h)2+(y−k)2=r2(x - h)^2 + (y - k)^2 = r^2(x−h)2+(y−k)2=r2Answer(x - h) ** 2 + (y - k) ** 2 == r ** 2(f) x=−b+b2−4ac2ax = \dfrac{-b + \sqrt{b^2 - 4ac}}{2a}x=2a−b+b2−4ac​​Answerx = (-b + math.sqrt(b * b - 4 * a * c)) / (2 * a)(g) an×am=an+ma^n 	imes a^m = a^{n+m}an×am=an+mAnswera ** n * a ** m == a ** (n + m)(h) (an)m=anm(a^n)^m = a^{nm}(an)m=anmAnswer(a ** n) ** m == a ** (n * m)(i) anam=an−m\dfrac{a^n}{a^m} = a^{n - m}aman​=an−mAnswera ** n / a ** m == a ** (n - m)(j) a−n=1ana^{-n} = \dfrac{1}{a^n}a−n=an1​Answera ** -n == 1 / a ** n

Question 8

Question 26Evaluate and Justify:(i) 22.0/7.0 - 22/7(ii) 22.0/7.0 - int(22.0/7.0)(iii) 22/7 - int (22.0)/7

Accepted Answer

(i) 22.0/7.0 - 22/7 ⇒ 0As values of 22.0/7.0 and 22/7 are equal, subtracting them will give the result as 0.0.(ii) 22.0/7.0 - int(22.0/7.0) ⇒ 3.142857142857143 - 3 ⇒ 0.142857142857143(iii) 22/7 - int (22.0)/7 ⇒ 0.0int (22.0) gives 22 so the expression becomes 22/7 - 22/7 which results in 0.0

Question 9

Question 27Evaluate and Justify:(i) false and None(ii) 0 and None(iii) True and None(iv) None and None

Accepted Answer

(i) This produces an error as false is an invalid literal in Python. It should be False. Had the expression being False and None, the return value will be False.(ii) This logical expression evaluates to 0. As first operand of and operator is false so it will return the first operand itself.(iii) This logical expression evaluates to None. As first operand of and operator is True so it will return the second operand.(iv) This logical expression evaluates to None. As first operand of and operator is false so it will return the first operand itself.

Question 10

Question 28Evaluate and Justify:(a) 0 or None and "or"(b) 1 or None and 'a' or 'b'(c) False and 23(d) 23 and False(e) not (1 == 1 and 0 != 1)(f) "abc" == "Abc" and not (2 == 3 or 3 == 4)(g) False and 1 == 1 or not True or 1 == 1 and False or 0 == 0

Accepted Answer

(a) 0 or None and "or" ⇒ 0 or None   [∵ and has higher precedence than or] ⇒ None(b) 1 or None and 'a' or 'b' ⇒ 1 or None or 'b' ⇒ 1 or 'b' ⇒ 1(c) False and 23 ⇒ False(d) 23 and False ⇒ False(e) not (1 == 1 and 0 != 1) ⇒ not (True and True) ⇒ not True ⇒ False(f) "abc" == "Abc" and not (2 == 3 or 3 == 4) ⇒ "abc" == "Abc" and not (False or False) ⇒ "abc" == "Abc" and not False ⇒ False and not False ⇒ False and True ⇒ False(g) False and 1 == 1 or not True or 1 == 1 and False or 0 == 0 ⇒ False and True or not True or True and False or True ⇒ False and True or False or True and False or True ⇒ False or False or False or True ⇒ False or False or True ⇒ False or True ⇒ True

Question 11

Question 29Evaluate the following for each expression that is successfully evaluated, determine its value and type for unsuccessful expression, state the reason.(a) len("hello") == 25/5 or 20/10(b) 3 < 5 or 50/(5 - (3 + 2))(c) 50/(5 - (3 + 2)) or 3 < 5(d) 2 * (2 * (len("01")))

Accepted Answer

(a) len("hello") == 25/5 or 20/10 ⇒ 5 == 25/5 or 20/10 ⇒ 5 == 5 or 2 ⇒ True or 2 ⇒ TrueThe type of result is Boolean.(b) 3 < 5 or 50/(5 - (3 + 2)) ⇒ True or 50/(5 - (3 + 2))   [∵ first operand is True, second operand is not evaluated so no division by 0 error happens] ⇒ TrueThe type of result is Boolean.(c) 50/(5 - (3 + 2)) or 3 < 5 ⇒ 50/(5 - 5) or 3 < 5 ⇒ 50/0 or 3 < 5 ⇒ Division by Zero ErrorAs the denominator of or operator's first operand is 0, Division by Zero error occurs.(d) 2 * (2 * (len("01"))) ⇒ 2 * (2 * 2) ⇒ 2 * 4 ⇒ 8The type of result is Integer.

Question 12

Question 30Write an expression that uses exactly 3 arithmetic operators with integer literals and produces result as 99.

Accepted Answer

9 * 10 + 21 % 12

Question 13

Question 33In Python, strings are immutable while lists are mutable. What is the difference?

Accepted Answer

In Python, strings are immutable means that individual letter assignment for strings is not allowed. For example:name='hello'
name[0] = 'p'The above Python code will cause an error as we are trying to assign some value to an individual letter of a string.Lists are mutable in Python means that we can assign values to individual elements of a list. For example:a = [1, 2, 3, 4, 5]
a[0] = 10The above Python code will work correctly without any errors as Lists are mutable in Python.

Question 14

Question 34How does the // operator differ from the / operator? Give an example of where // would be needed.

Accepted Answer

The Division operator (/) divides its first operand by second operand and always returns the result as a float value whereas Floor Division operator (//) divides its first operand by second operand and truncates the fractional part of the result and returns it as an int value. Floor Division operator is useful in situations where we only need the integer part of the division operation result. For example, to determine how many minutes are there in some given number of seconds:secs = 2565
mins = 2565 // 60

Question 15

Question 36What are main error types? Which types are most dangerous and why?

Accepted Answer

The types of errors are:Compile Time Errors (Syntax errors and Semantic Errors)Runtime ErrorsLogical ErrorsLogical Errors are the most dangerous as they are hardest to prevent, find and fix.

Question 16

Question 37Correct any false statements:(a) Compile-time errors are usually easier to detect and to correct than run-time errors.(b) Logically errors can usually be detected by the compiler.

Accepted Answer

(a) The statement is correct.(b) The statement is incorrect. The correct statement should be:Logical errors cannot be detected by the compiler.

Source: This question is from Data Handling, Computer Science &mdash; Class 11, CBSE Board.
Key Concepts CoveredThis question tests your understanding of the following concepts from the chapter Data Handling: Question, Correct, False, Statements, Compile, Time. These are fundamental topics in Computer Science that students are expected to master as part of the CBSE Class 11 curriculum.A thorough understanding of these concepts will help you answer similar questions confidently in your CBSE examinations. These topics are frequently tested in both objective and subjective sections of Computer Science papers. We recommend revising the relevant section of your textbook alongside practising these solved examples to build a strong foundation.
How to Approach This QuestionRead the question carefully and identify what is being asked. Break down complex questions into smaller parts. Use the terminology and concepts discussed in this chapter. Structure your answer logically — begin with a definition or key statement, then provide supporting details. Review your answer to ensure it addresses all parts of the question completely.
Key Points to RememberWrite programs with proper indentation and comments.
Trace through your code with sample inputs to verify correctness.
Explain the logic behind each step of your solution.
Familiarise yourself with common library functions and methods.
Related Questions from Data HandlingQ1: Question 1 What are data types in Python? How are they important?
Q10: Question 10 Are these values equal? Why/why not? 20 and 20.0 20 and int(20) str(20) and str(20.0)...
Q11: Question 7 Make change in the expression for z of previous question so that the output produced is...
Q12: Question 12 What is the difference between implicit type conversion and explicit type conversion?
Q13: Question 13 Write a program that generates six random numbers in a sequence created with (start,...
Practice more questions from Data Handling &mdash; Computer Science, Class 11 CBSE

Question 17

Question 38Differentiate between a syntax error and a semantics error.

Accepted Answer

Syntax ErrorSemantics ErrorSyntax errors occurs when the rules of the programming language are violated.Semantic errors occur when the statement are not meaningful.Example:x = falseExample:x * y = z

Question 18

Question 39Differentiate between a syntax error and a logical error in a python program. When is each type of error likely to be found?

Accepted Answer

Syntax ErrorLogical ErrorSyntax Errors occur when we violate the rules of writing the statements of the programming language.Logical Errors occur due to our mistakes in programming logic.Program fails to compile and execute.Program compiles and executes but doesn't give the desired output.Syntax Errors are caught by the compiler.Logical errors need to be found and corrected by people working on the program.Syntax errors are found at compile type whereas Logical errors are found when the program starts executing.

Question 19

Question 40What is the difference between an error and exception?

Accepted Answer

An Error is a bug in the code that causes irregular output or stops the program from executing whereas an Exception is an irregular unexpected situation occurring during execution on which programmer has no control.

Question 20

Question 5aWhat will be output produced by following code? State reason for this output.a, b, c = 1, 1, 2
d = a + b
e = 1.0
f = 1.0
g = 2.0
h = e + f
print(c == d)
print(c is d)
print(g == h)
print(g is h)

Accepted Answer

OutputTrue
True
True
False
ExplanationValue of d becomes 2 and as values of c and d are equal so print(c == d) prints True.

Data Handling

Type A: Short Answer Questions/Conceptual Questions

Type B: Application Based Questions

Type C: Programming Practice/Knowledge based Questions