Virtual ground 

Understood more watching 30 minutes of these videos than I did writing 4 hours worth of lecture notes. What is life without Khan Academy

Video makes the concept of op-amp virtual ground easy to understand. Thank you !

U basically summed up 30% of my report in 5mins thx 🙏

after so many videos i found this one helpful !!!!

Thank Khan academy for making life easy and simple ,and making better;

wait, so when an op amp is running how it should, both input voltages are equal? and when one of them is connected to ground that means both would be 0?

How bout voltage follower, can it be used to create "virtual ground" at its output? Looks like it has same meaning.

Thank you so much from Milan, Italy 🙏🙏🙏

If both inputs are ground or virtually ground, what's the point of putting this into your circuit?

Thanks, just thanks

Good stuff!

but why would you take gain equal to 10^6 in a closed loop configuration ? since you have considered closed loop to explain virtual ground .

Thanks khan

What if i applied 1v input

Why do you use the open loop gain “A” in your explanation when the circuits have clearly feedback loops, and the gain is way smaller by orders of magnitude. Maybe I miss something, but this is confusing.

if the differential voltage (v+ = v-) is '0' then the output will be zero, right?

Great.....

how does the power supply help getting that 6 volt from 0 volt???

If you're going to cross your T's, you better dot your I's.

What's the application he use

1:34 Where does [ V(in) = V(0) / A ] come from? It makes no sense to me.

most people in comments are mad not because of the video but because they couldn't understand the concept 😂although they watched and read alot like me 😅 what i concluded is that most of the people explaining this concept or the opamp in general don't really understand what they are talking about they just memorized the explanation because every single article every single video is saying the same thing word for word i mean come onnn people

Geee, why when learning algebra in school the books used semi meaningless examples... teach simple op-amps as real world algebra problems... this would also encourage students to learn a little of what engineering is about? most beginning algebra classes are vague on teaching the students on how to use algebra in earning a life-time income and not just to pass the class! thanks...:)

what if opamp was saturated??

Is this Leo's Bag of Tricks?

For people still confused, it's a voltage divider. The node created between connecting the 2 resistors in series is half of the total supply; relative to when you first learn series circuits and are measuring voltage drops across a half dozens resistors or so when getting started in your education. If you check the positive of your supply with your meter to the center node, you will see 6v, and when you check the negative of your supply to the center node, you will see 6v. In relationship to the positive supply, the voltage drop across 1 resistor at that point is -, and more positive on it's opposite side, and in relationship to the negative side of your supply, the 6v is +, and more negative on the opposite side. Each resistor required 6 volts to "energize" the atoms into alignment so electrons can skip across their valiance rings. Some op amps and larger devices need dual source because of the bipolar semiconductor material in their integrated circuitry. *Relate it to when you bias the base current of a BJT, and connect a resistor from each side of your power supply to the single electrode of the base.* The op amp is shifting in polarity, and with each change of 1/2 cycle to the other, needs the opposite polarity reference to bias itself properly. It is only a reference of polarity, not actually quite the same as the base of a BJT requiring both at the same time to free up and activate charge carriers. *I've never understood why not a single video or website online bothers to explain it correctly as I just did when many of them are posted by college professors!* It's easily understood when the explanation relates it to a series circuit, voltage drops across devices in the series circuit and measuring each node to determine which side is more positive and which side is more negative.

Why does this sound like Nauman Ali Khan is teaching?😂

You haven't explained virtual ground,you just explained the configuration which causes it,not satisfied

so basically you can get 6V from 0V? wow

hek lool... thats an arabic word meaning like i want

Sounds like Alec Baldwin.

It is a TERRIBLE idea to use the term VIRTUAL GROUND to describe the summing junction of a inverting op amp ! How can one explain that the summing junction voltage v(+) minus V(-) increases >>6uv when Vin frequency > f cutoff ? ?

I'm watching it at 1.25x rate

Your algebra is still a sloppy mess. *Also*, it might help... If you are going to be using "v"s and "u"s and also writing your "v"s as "u"s, that you actually write them properly and consistently. Half your "v"s are "u"s and the other half are "v"s. The "u"s are turning into "v"s whenever there is a "u" sometimes, or something. There is almost no logic to it. Drawing your "v"s as "u"s is obviously contrived (maybe some person you want to emulate does it?), because when you are not thinking you draw them as "v"s. I saw you go back and draw the tail on them to make them "u"s after (they were "v"s). Confused?