Seven-segment display — segments required to show the digit 2 For a standard seven-segment display with segments a–g, which segments must be active to display the decimal digit 2?
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Aa, b, d, e, and g
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Ba, b, c, d, and g
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Ca, c, d, f, and g
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Da, b, c, d, e, and f
Answer
Correct Answer: a, b, d, e, and g
Explanation
Introduction / Context:Seven-segment displays render decimal digits using combinations of the segments a through g. Knowing the correct segment activation pattern is essential for designing decoders and driving logic for numeric indicators in embedded systems and instrumentation.
Given Data / Assumptions:
- Standard seven-segment labeling: a (top), b (upper-right), c (lower-right), d (bottom), e (lower-left), f (upper-left), g (middle).
- We want to display the decimal digit 2.
- Common-cathode/common-anode electrical polarity is irrelevant to the logical pattern.
Concept / Approach:The digit 2 consists of the top bar, upper-right, middle, lower-left, and bottom bars illuminated. That corresponds to segments a, b, g, e, and d (order may vary). Segment naming confirms the exact set needed.
Step-by-Step Solution:
1) Start with the top bar → segment a ON.2) Upper-right vertical → segment b ON.3) Middle bar → segment g ON.4) Lower-left vertical → segment e ON.5) Bottom bar → segment d ON.Verification / Alternative check:Compare with other digits: “3” would be a, b, c, d, g (no e), confirming that “2” uniquely uses e instead of c.
Why Other Options Are Wrong:
- a, b, c, d, g: that shows “3,” not “2.”
- a, c, d, f, g: that shows “5” (left side segments differ).
- a, b, c, d, e, f: that would illuminate six segments and does not correspond to a standard single digit.
Common Pitfalls:Mixing up e and c (left vs. right lower verticals) or forgetting the middle bar g for “2.”
Final Answer:a, b, d, e, and g