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Movement of Charges in Potential Fields

Patrick Ford
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Hey, guys. So now that we've talked about electric potentials, it's time to talk about very quickly. How charges move inside of potential feels there's not a whole lot of calculations that you'll need, but it's definitely some conceptual points. Need to know. So let's check it out. So basically, the whole deal is that positive charges will always move towards lower potentials and negative charges. According being the opposite of those will always move towards higher potentials. The way that I like to think about it is think back when we're talking about energy. If you have, like a roller coaster like this, then Mass will always try to move towards the lower potential. It's kind of like that, but that's basically the whole entire game, and it's because potential is when we're talking about electric charges is a field that sort of provides the motivation for charges to move, and it gives them potential energy, so positive charges always want to reduce that potential and the negative charges always gonna do the opposite of that. All right, so before we talk about how electric fields are gonna be sort of incorporated into potentials, let's go ahead and just do this quick example. So we have an electron that's at rest. So we have an electron that's at rest, and we have two points. So we've got this point right here. A and we're told that that is at 10 volts, and then we have another point B, that zero volts. So somehow we actually know what the potentials are. Both of these points. And then we're gonna have to stick an electron inside of here. And we have to figure out which direction that that electrons gonna move to while that electron is a negative e, which means it's a negative charge. And negative charges always move to where they always move towards higher potentials. So that means that this electron is always just gonna go to the left, and that's the answer. So it's gonna go towards a and that's the answer. All right, so let's move on to this next question here because now we're actually gonna be relating the way that charges move and potentials with electric fields. So you have a metal rod, and that's actually important because that metal rod means that is a conductor. It's placed in a uniformed electric field and I'm just gonna have that electric field has a strength of e. And we're supposed to figure out which end of this rod here is at a higher potential. Okay, so basically, we know how charges in electric fields move. So if we have a positive charge, that's inside of this. We know that the force on those charges always wants to go with the flow, right, because of f equals Q E. So we know that the force, if we have a charge in electric field if that charges positive, always wants to move in the same exact direction or as it's the opposite for negative charges, any negative charge basically wants to go against the flow. So we can say if this is if this charge right here, which is negative, wants to go against the flow and we know that negative charges always move towards higher potentials, then that means that the left side of this electric field has to be one with higher potential, whereas the right side is gonna be the one with lower potential. So basically kind of follows their discussion of charges inside of electric fields, and those were basically the answers. This is high potential, and this is low potential. Alright, guys, let me know if you have any questions