Extra exam question E7G03
Subelement E7, PRACTICAL CIRCUITS· Group E7G
What is the typical input impedance of an op-amp?
- A.100 ohms
- B.10,000 ohms
- C.Very low
- D.Very high (correct answer)
WhyAn op-amp typically has very high input impedance. An op-amp typically has a very high input impedance, drawing essentially no current from whatever is driving its input, another of the ideal characteristics that makes op-amps easy to use in a wide range of circuits without loading down the signal source, answer D. It isn't very low, and it isn't a fixed moderate value like 100 or 10,000 ohms, real op-amps are designed to approach a very high input impedance, not a specific number in that range.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2024-2028 NCVEC Element 4 pool (public domain); the explanation above is original writing, see our methodology.
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