Exam-style question
Try this first
A simple SR latch (active‑low) has its S input high at 5 µs and its R input low at 15 µs. When does the output Q first become high?.
- A.At 5 µs when S goes high
- B.At 15 µs when R goes low
- C.At 20 µs after both changes
- D.It never becomes high
Model answer
What a good answer should say
- At 15 µs when R goes low
Explanation
Why this works
Evidence: The diagram shows S high at 5 µs and R low at 15 µs. Interpretation: In an active‑low SR latch, Q becomes high only when R is low.
Implication: The output will change to high at the moment R goes low. Conclusion: The correct answer is that Q first becomes high at 15 µs.
Common mistake
No common mistake is linked to this question yet.