Connecting the (+) terminal of an inverting op-amp to ground forces the (–) terminal to_____________?
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Answer: B. Be virtual ground
Explanation
Inverting op-amp configurations connect the non-inverting terminal directly to a ground reference point. Negative feedback forces the differential voltage between the inverting and non-inverting terminals to approach zero. Because the non-inverting terminal is at zero volts, the inverting terminal is held at virtual ground potential. Virtual grounds act as zero-volt nodes that do not sink current to an actual earth ground connection. Negative feedback loops continuously adjust the output to counteract any voltage deviation at the inverting input. This virtual short-circuit property simplifies the analysis of inverting amplifier and summing amplifier circuits.
Analog integrators and differentiators rely on virtual ground nodes to control charge accumulation precisely. Audio mixing consoles use virtual grounds to sum multiple input signals without channel crosstalk interference. Signal processing circuits depend on virtual grounding to maintain high linearity and low distortion. Inverting op-amps still require input resistors to set gain and establish proper input current scaling. High reverse current describes semiconductor junction behavior rather than virtual ground node characteristics. Not invert the signal describes non-inverting amplifier behavior rather than the inverting configuration.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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