Which of the following statements is/are TRUE with respect to an ideal op-amp?
Show Hint
- It has an infinite input resistance
- It has an infinite output resistance
- It has an infinite open-loop differential gain
- It has an infinite open-loop common-mode gain
The Correct Option is A, C
Solution and Explanation
1. Infinite input resistance: This means that the current into the input terminals of the op-amp is zero. Therefore, the ideal op-amp has infinite input resistance, which is why Option (A) is true.
2. Zero output resistance: An ideal op-amp has zero output resistance, not infinite output resistance, which makes Option (B) false.
3. Infinite open-loop differential gain: The ideal op-amp has an infinite gain when the differential input is applied. Thus, Option (C) is true.
4. Zero open-loop common-mode gain: In the ideal op-amp, the common-mode gain is zero, not infinite. Hence, Option (D) is false. Thus, the correct answer is (A) and (C).
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