How does negative feedback influence the gain of an op-amp in practical circuits?

Negative feedback takes a small part of the output and returns it to the input, forcing the op‑amp to adjust until the input difference is nearly zero. Because of this, the overall closed‑loop gain is set by the external resistor network instead of the op‑amp’s huge open‑loop gain, making the gain predictable and stable. The feedback also reduces the amplifier’s sensitivity to temperature, supply voltage, and component variations, while widening the bandwidth and lowering distortion. For instance, an inverting amplifier with a 10 kΩ input resistor and a 100 kΩ feedback resistor will have a closed‑loop gain of –10, regardless of the op‑amp’s 100 000‑fold open‑loop gain. Thus, negative feedback turns the op‑amp into a precise, low‑noise amplifier whose gain is determined by the chosen resistor values.