Class 12 Exception Handling in Python Mock Test (CBSE)

Topics in Exception Handling in Python

• Syntax errors
• Exceptions
• Built-in exceptions
• Raising exceptions: raise and assert
• Handling exceptions with try and except
• The else clause
• The finally clause

Exception Handling in Python practice questions with answers

1. Q1Multiple choice·1 mark
   Which of the following Python statements will fail with a SyntaxError when the program is run?

   1. (a)total = 45 + "38"
   2. (b)print("Total:", 45 + 38)
   3. (c)age = int("twelve")
   4. (d)if marks > 40 print("Pass")
   Show answer and step marks

   1. Correct option: (d) if marks > 40 print("Pass") is missing the colon after the condition, so Python reports a SyntaxError before the program runs.+1

   Answer: (d)
2. Q2Multiple choice·1 mark
   A train journey planner program asks the passenger for the distance travelled and prints the fare: try: distance = float(input("Distance covered (km): ")) fare = distance × 2.5 print("Fare:", fare) except ValueError: print("Enter a valid distance") finally: print("Journey record saved") The passenger enters 120 when the input is requested. Which output is printed?

   1. (a)Fare: 300.0 only
   2. (b)Enter a valid distance followed by Journey record saved
   3. (c)Journey record saved only
   4. (d)Fare: 300.0 followed by Journey record saved
   Show answer and step marks

   1. Correct option: (d) Fare: 300.0 followed by Journey record saved+1

   Answer: (d)
3. Q3Short answer·2 marks
   The code below is run in IDLE. readings = [12, 15, 9] for i in range(4): print(readings[i] × 2) The program prints 24, 30 and 18, and then stops with an error message. (a) Identify the built-in exception that Python raises when the program stops. [1] (b) State the value of i in the iteration where the program stops. [1]
   Show answer and step marks

   1. Correct: IndexError, because readings[3] asks for a position that does not exist in a list of three elements.+1
   2. Correct: i = 3, the fourth pass of the loop, which is the first pass with no matching element in readings.+1

   Answer: (a) IndexError; (b) i = 3
4. Q4Short answer·3 marks
   Study the code given below. try: num = int(input("Enter a number: ")) print(10 / num) except ZeroDivisionError: print("Cannot divide by zero") The user enters 0 when the input is requested. (a) Name the block of the code in which the statements that may cause an error are written. [1] (b) Name the exception that is handled by the code when the user enters 0. [1] (c) State the message printed by the program when the user enters 0. [1]
   Show answer and step marks

   1. (a) The statements that may cause an error are written in the try block.+1
   2. (b) The division by zero raises ZeroDivisionError, which is handled by the except block.+1
   3. (c) The except block prints the message: Cannot divide by zero+1

   Answer: (a) try block; (b) ZeroDivisionError; (c) Cannot divide by zero
5. Q5Short answer·3 marks
   Compare the raise statement and the assert statement in Python. (a) Explain how the raise statement decides whether to raise an exception. [1] (b) Explain how the assert statement decides whether to raise an exception, and state the exception it raises. [1] (c) Write a raise statement that raises a ValueError with the message "Age cannot be negative" when $age < 0$. [1]
   Show answer and step marks

   1. (a) The raise statement raises the named exception unconditionally, as soon as the statement is executed.+1
   2. (b) The assert statement evaluates the given condition; if the condition is False it raises AssertionError, otherwise the program continues.+1
   3. (c) if age < 0: raise ValueError("Age cannot be negative")+1

   Answer: (a) raise always raises the given exception when reached; (b) assert raises AssertionError only when its condition is False; (c) if age < 0: raise ValueError("Age cannot be negative")

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