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MAD II · Vue reactivity, computed & watchers

16 questions · 52 marks · 5 papers

Answer key

Indian Institute of Technology Madras

BS Degree Programme · Examination & Study Paper

Modern Application Development II

Vue reactivity, computed & watchers

Official Paper

Examination Instructions & Guidelines

Solve on notebook/paper first before checking solutions.
MCQ: Exactly 1 option is correct. Negative marking applies.
MSQ: One or more options correct. Select all to score.
NAT: Numerical response. No negative marking.
Scientific calculator allowed for all calculations.
Official answer key is sealed at the end of this sheet.

Quiz 1 · 26 Oct 2025 (AN)Quiz 1

Q1MCQ3 Marks·Choose one option
Key ↓
1. A
2. B
3. C
4. D
Q2NAT3 Marks·Write the number
Key ↓
Your answer:

End Term · 31 Aug 2025 (FN)End Term

Q3MCQ2 Marks·Choose one option
Asked 2 times Key ↓
1. AThe component will reload when data changes
2. BThe DOM updates automatically when the underlying reactive data changes
3. CAll function calls become asynchronous
4. DIt disables direct access to state
Read the passage below, then answer Q4–Q6
Based on the above data, answer the given subquestions.
Q4MCQ3 Marks·Choose one option
Key ↓
After step 2 (selecting two tasks), what is the value of selectedTasks.length?
1. A0
2. B1
3. C2
4. D3
Q5MCQ3 Marks·Choose one option
Key ↓
What happens when the user clicks "Select" on Design UI again (step 3)?
1. AIt is added again, making the total 3
2. BIt replaces the previous task
3. CNothing changes, no duplicate is added
4. DVue throws a warning about duplicate keys
Q6MSQ3 Marks·Choose all correct options
Key ↓
Which of the following statements about this component setup are true?
1. A
2. B
3. C
4. D

End Term · 31 Aug 2025 (AN)End Term

Q7MCQ2 Marks·Choose one option
Asked 2 times Key ↓
What does "reactivity" mean in the context of frontend frameworks like Vue.js?
1. AThe component will reload when data changes
2. BAll function calls become asynchronous
3. CIt disables direct access to state
4. DThe DOM updates automatically when the underlying reactive data changes
Q8MCQ3 Marks·Choose one option
Key ↓
1. AApp 1 only shows data
2. BBoth show “Hello from App 2”
3. CBoth show “Hello from App 1”
4. DEach renders its own message independently
Read the passage below, then answer Q9–Q11
Scenario
1. The component is loaded.
2. User clicks "Mark Complete" for the task named Build Project.
3. User clicks "Show Completed" button again.
Q9MCQ3 Marks·Choose one option
Key ↓
After step 2 (Mark Completed is clicked), what tasks are shown?
1. ALearn Vue
2. BLearn Vue, Build Project, Test App
3. CTest App only
4. DNone
Q10MCQ3 Marks·Choose one option
Key ↓
After step 3 (Mark Complete is clicked on Build Project), how many completed tasks are reported in the UI?
1. A1
2. B2
3. C3
4. D0
Q11MSQ3 Marks·Choose all correct options
Key ↓
Which of the following are true about this component’s behavior?
1. A
2. B
3. C
4. D

End Term · 22 Dec 2024 (FN)End Term

Q12MCQ3 Marks·Choose one option
Asked 2 times Key ↓
1. AThe watcher will not be triggered because “name” is a nested property of “user” object.
2. BThe watcher will be triggered and log "User object changed: { name: 'Bob', age: 30 }".
3. CThe watcher will be triggered, but it will only log the new “name” value, i.e., “Dev”, and not the entire user object.
4. DThe watcher will throw an error because deep watching is not supported on nested objects.
Q13MCQ4.5 Marks·Choose one option
Key ↓
1. ALikes: 5
2. BLikes: 8
3. CLikes: 6
4. DLikes: 9

End Term · 22 Dec 2024 (AN)End Term

Q14MCQ4.5 Marks·Choose one option
Asked 2 times Key ↓
1. AThe watcher will be triggered and log "User object changed: { name: 'Bob', age: 30 }".
2. BThe watcher will not be triggered because “name” is a nested property of “user” object.
3. CThe watcher will be triggered, but it will only log the new “name” value, i.e., “Dev”, and not the entire user object.
4. DThe watcher will throw an error because deep watching is not supported on nested objects.
Q15MCQ4.5 Marks·Choose one option
Key ↓
1. A[2, 4, 6]
2. B[2, 4, 6, 8]
3. C[4, 8, 12]
4. D[2, 4, 6, 16]
Q16MCQ4.5 Marks·Choose one option
Key ↓
1. ARequired
2. BInvalid format, Email exists, Required
3. CRequired, Email exists
4. DValidating..., Required

Official Key

Master Answer Key & Explanations

Official answer keys from IIT Madras BS past papers. Click any question to review.

Reveal Key

Q1D

Q23

Q3B

Q4C

Q5C

Q6A, B, C

Q7D

Q8D

Q9A

Q10B

Q11C, D

Q12B

Q13B

Q14A

Q15B

Q16A

Questions and answer keys are reproduced from the official IIT Madras BS papers. Topics and repeated question types are BTechi’s own grouping. BTechi is not affiliated with IIT Madras.