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24. Electric Force & Field; Gauss' Law

Charging By Induction


Charging By Induction

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Hey, guys. So in this video, we're gonna talk about a special kind of charging called Charging by induction. We saw how conduction works. Now you need to know the processes and steps involved in induction. There's not gonna be a lot of calculations, but you're definitely you need to know. It's let's check it out. So conduction or induction is a method of charging objects without touching. Now we saw in the last video in the last couple of videos how conduction works with contacts. In other words, these objects have to touch. But the net effect an induction is that just like conduction, the object is left with a net charge. So let's go through the steps one by one. The first is that you take a neutral conductor. So neutral means the same amount of positive and negative charges, and you connected to something called the ground. Now this little symbol right here, this little three bars means the ground, and that ground is basically just a source and also a sink off electric charges. Now sources are things that freely give up electrons. They are a source of electrons and electric charges, while sinks receive electrons and electric charges. The most kind of the most common type of ground is literally the physical ground that you stand on the earth. It is a massive reservoir of charges it can freely give and also accept charges because over all those small charges don't really have anything don't really have any impact on the overall charge of the earth. So you have these, you know, I'm just There's gonna be, like, representing a billion charges or whatever an infinite amount of charges. So that's the step one. You're gonna connect this neutral, the neutral conductor to the ground. Step two is we're gonna bring a positively charged rod near that conductor. Now there's a couple of things that are happening here we saw in previous videos we saw before. How when you bring a charged rod close to a conductor, you have polarization. So all of these electric charges that have already existed inside of the neutral conductor we'll start to pile up on the left because they want to attract the positively charged rod and the positive charges start to accumulate on the right hand side. But now that you have a reservoir that you're connected to from this ground. What happens is that this step will pull charges or these charge Rod will pull charges in from the ground into the connector, and they're starting to the conductor. So the words you have these electrons that air locked in these atoms, and they'll basically start following this connection up here, and basically they'll pile up on the connect on the conductor again, trying to attract the positive charges from the Rod. So now I just want to mention that if this rod was negatively charged, the exact opposite would happen. You would actually have electrons leave into the ground. Um, but anyways, that's just a different way that could possibly happen. So the opposite would happen if the charge was the opposite. So this next step here is that now all of these electric charges air pile up against this thing. And attracting this positive rod you have to do is you have to sever the connection between the ground and the conductor right here. Because if you were to just remove this class rod or this possibly charged Rod, all of these extra charges now would repel and go back into the earth. So this step right here where you're cutting the connection between the ground and the conductor. What it does is it prevents the charges from escaping, and that's the important step. So now, once you've severed this connection and these electrons, Irv charges can no longer freely go and back and forth between the source or the reservoir. Now, you remove the charge rod at the end. So, for instance, we're just gonna take this charged Rod, and we're just gonna pull it away. And the effect is that this conductor now has an imbalanced number of charges. So, for instance, will have, like, seven positive negative charges and maybe, like four positive charges or something like that, right? I'm just making up numbers here. So the effect is that even though we didn't actually touch the conductor at any point, the conductor is now charged, and that's the important part. Just again. Want to reiterate that if this thing were negative, if the charge rod were negative, the opposite effect would happen. Theologians would escape down into this reservoir, and if you removed it, you would end up with a positively charged conductor again. All right, so let me know if you guys have any questions with this