So in an OP AMP, one of the main features is the feedback loop that goes from the output to the input. What does that do exactly, like how does that contribute to the amplifying of electric signals?
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Op amps have very high gain, so a small difference at the input terminals results in a large change in the output. Open loop (ie no feedback network) is useless for most things except to do a comparison of “is input 1 > input 2?” because the output will slam to one of the power rails.
Feedback networks are used to control the effective gain of the amplifier, which will make it into something usable. A negative feedback network specifically will take some portion of the output and mix it back in with the input terminals, thus reduce the effective difference between the input terminals and limiting the effective gain.
An analogy: You’re having a discussion with your partially deaf grandparent. He starts to say something, but ends up yelling really loudly. You tell him to turn on his hearing aid. Now he has some feedback on his voice volume and turn it down to a normal level.
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