Computer Science · Sample Paper 1

General instructions

Section A · Objective

1. Question 11 mark

   Which of these is volatile memory?

   1. A.ROM
   2. B.RAM
   3. C.hard disk
   4. D.SSD
2. Question 21 mark

   Which translator converts a whole program into machine code at once?

   1. A.interpreter
   2. B.assembler
   3. C.compiler
   4. D.loader
3. Question 31 mark

   $(1011)_2$ in decimal is

   1. A.9
   2. B.11
   3. C.13
   4. D.10
4. Question 41 mark

   $(2F)_{16}$ in decimal is

   1. A.47
   2. B.45
   3. C.31
   4. D.63
5. Question 51 mark

   Which encoding scheme can represent characters of all world languages?

   1. A.ASCII
   2. B.ISCII
   3. C.Unicode
   4. D.BCD
6. Question 61 mark

   A network of everyday devices that exchange data is called

   1. A.cloud
   2. B.IoT
   3. C.blockchain
   4. D.VR
7. Question 71 mark

   In a flowchart, a decision is shown by a

   1. A.rectangle
   2. B.oval
   3. C.diamond
   4. D.parallelogram
8. Question 81 mark

   What is the output of print(7 // 2)?

   1. A.3.5
   2. B.3
   3. C.4
   4. D.1
9. Question 91 mark

   Which of these is a valid identifier in Python?

   1. A.2total
   2. B.total-sum
   3. C._total
   4. D.for
10. Question 101 mark

    What is the value of 2 ** 3 ** 2?

    1. A.64
    2. B.512
    3. C.36
    4. D.12
11. Question 111 mark

    How many times does this loop run?

    for i in range(2, 10, 3):
        print(i)
    

    1. A.2
    2. B.3
    3. C.4
    4. D.8
12. Question 121 mark

    Which statement skips the rest of the current loop iteration?

    1. A.break
    2. B.pass
    3. C.continue
    4. D.exit
13. Question 131 mark

    A function that has no return statement returns

    1. A.0
    2. B.None
    3. C.False
    4. D.an error
14. Question 141 mark

    If s = 'PYTHON', what is s[1:4]?

    1. A.'PYT'
    2. B.'YTH'
    3. C.'YTHO'
    4. D.'THO'
15. Question 151 mark

    What does 'banana'.find('n') return?

    1. A.1
    2. B.2
    3. C.3
    4. D.−1
16. Question 161 mark

    L = [1, 2, 3]; L.append([4, 5]). What is len(L)?

    1. A.3
    2. B.4
    3. C.5
    4. D.6
17. Question 171 mark

    Which method removes and returns the last item of a list?

    1. A.remove()
    2. B.pop()
    3. C.del
    4. D.clear()
18. Question 181 mark

    Which of these is a tuple with one element?

    1. A.(5)
    2. B.(5,)
    3. C.[5]
    4. D.{5}
19. Question 191 mark

    Sending fake messages to trick people into revealing passwords is called

    1. A.hacking
    2. B.phishing
    3. C.spamming
    4. D.trolling
20. Question 201 mark

    Assertion (A): A list can't be used as a dictionary key.

    Reason (R): Dictionary keys must be immutable.

    1. A.Both Assertion (A) and Reason (R) are true, and R is the correct explanation of A.
    2. B.Both Assertion (A) and Reason (R) are true, but R is not the correct explanation of A.
    3. C.Assertion (A) is true, but Reason (R) is false.
    4. D.Assertion (A) is false, but Reason (R) is true.
21. Question 211 mark

    Assertion (A): s = 'cat'; s[0] = 'b' changes s to 'bat'.

    Reason (R): Strings in Python are immutable.

    1. A.Both Assertion (A) and Reason (R) are true, and R is the correct explanation of A.
    2. B.Both Assertion (A) and Reason (R) are true, but R is not the correct explanation of A.
    3. C.Assertion (A) is true, but Reason (R) is false.
    4. D.Assertion (A) is false, but Reason (R) is true.

Section B · Very short answer

1. Question 222 marks

   Differentiate between system software and application software with one example each.

2. Question 232 marks

   Convert $(45)_{10}$ to binary and octal.

3. Question 242 marks

   Write the output:

   a, b = 10, 3
   print(a % b, a / b)
   print(a > b and b > 5)
   

4. Question 252 marks

   Rewrite using a while loop:

   for i in range(1, 6):
       print(i * i)
   

5. OR

   Question 252 marks

   Find the errors and rewrite the code correctly:

   x = int(input('Number'))
   if x % 2 = 0
       print('Even')
   else
       print('Odd')
   

6. Question 262 marks

   Write the output:

   s = 'Hello World'
   print(s.upper())
   print(s.split())
   

7. Question 272 marks

   Write the output:

   d = {'a': 1, 'b': 2}
   d['c'] = 3
   d['a'] = 10
   print(d)
   print(d.get('z', 0))
   

8. Question 282 marks

   What is a digital footprint? Give one difference between an active and a passive digital footprint.

Section C · Short answer

1. Question 293 marks

   Write an algorithm (or flowchart) to find the largest of three numbers.

2. Question 303 marks

   Write a Python program that reads a list of numbers and prints how many are even and how many are odd.

3. OR

   Question 303 marks

   Write a Python program to check whether a string is a palindrome.

4. Question 313 marks

   What is the difference between a local and a global variable? Write the output:

   x = 5
   def f():
       global x
       x = x + 10
       return x
   print(f(), x)
   

Section D · Long answer

1. Question 324 marks

   Write a function factorial(n) that returns n!, and use it to print the value of ⁵C₂ = 5! / (2! 3!).

2. Question 334 marks

   Write a program that counts how many times each character appears in a string entered by the user, using a dictionary.

3. Question 344 marks

   Write a program to perform a linear search for a number in a list and print its position, or 'Not found'.

4. OR

   Question 344 marks

   Write a program to print the pattern:

   1
   1 2
   1 2 3
   1 2 3 4
   

5. Question 354 marks

   Explain the three kinds of intellectual property rights with an example of each. What is plagiarism?

Section E · Long answer

1. Question 365 marks

   Explain any five emerging technologies with one real-life application each.

2. Question 375 marks

   Write a menu-driven program that keeps a list of marks and lets the user (1) add a mark, (2) display all marks, (3) show the average, (4) exit.

3. OR

   Question 375 marks

   Write a program to store names and phone numbers of n friends in a dictionary, then search for a name and print the number, or 'Not found'.