Find Equivalent Capacitance #1

by Patrick Ford
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Hey, guys, let's get a little bit more practice with solving equivalent. Capacitance is in complicated circuit problems. Okay, so we've got all these four capacitors right here. All of them are labeled, so we know we have to work from the inside out. If we have combinations, we have some parallels. We have some Siri's. So, basically, what's happening is that if I could collapse all of this down to a single capacitor, then all of these two will basically this one and this one will be in serious with each other. But if I look a little bit more carefully, a little bit more closely than what I have a situation where I have these three capacitors and I have these are in parallel. And if I look even closer, I've got these two capacitors right here are in serious with each other. So we have to do is we have to work from the inside outwards. So that's step one we're gonna be solving with the equivalent capacities is of these two. In other words, when we do that, we're gonna get a circuit that basically looks like this. We're gonna have an equivalent capacities right here. we have the one on the bottom, which we know is three ferrets. And then these two things are gonna be in parallel with each other, and then they're gonna be in Siris with the five Fareed Capacitor. So we need to figure out what is this ce que right here? And that's gonna be the one in red. Okay, so we know that we're dealing with a Siri's, and we have to capacitors, which means we can use our shortcut equation for equivalent capacitance C e Q is just gonna be two times two divided by two plus two. Right, The C one C two divided by C two C one plus C two. Now, both of these happened before, which means that the equivalent capacity is equal to one ferret. Okay, now, what have is I have these two or these So the equivalent capacity right here and it's one of the bottom. So, in other words, this situation right here I have it in parallel. So that means you need to use my parallel equations for ce que and what happens is when I figure out what this equivalent capacity is, this is gonna behave the same way, Because if I had a single capacitor right here, that's gonna be in blue. And then that capacitor was in parallel with the five ferret capacitor. Okay, so these equivalent capacities right here is going to be Well, I have them in parallel. So that means all I have to do is just add these things together. So I have one. Ferid plus three ferrets is just four ferrets, and that's it. So I've got four ferrets right here. Okay. Now, for the last part, the last step, the equivalent capacitance for the entire circuit. Now I have in Siris. So this was parallel, and then this is gonna be in Siris. Now, I have, uh, two capacitors that I have here. So I could use really either one of the equations that I have So I could use the fact that the equivalent that one over e the equivalent capacitance is gonna be 1/4 plus 1/5. And let's see 1/4 plus 1/5. The common denominator is 20. This is gonna be 5/20. This is before over 20. So this is gonna be 9/20. But I have to take the reciprocal once I do this. So that means that my equivalent capacitance C e Q is gonna be 20/9. We could have done that or on alternate way, so I have, Or we could have just done that. The equivalent capacitance for two capacitors is going to be the multiplication of these 24 times five divided by four plus five. And we would have gotten the exact same thing, 20/9 ferrets. So either way, using either one of those approaches, we get the correct equivalent capacitance for the entire circuit. So that means that all of these forced capacitors behave as if you had just had a single capacitor of 20/9 ferrets. And that's the answer. All right, let me know if you guys have any questions. There's a very, very useful step by step process and how to basically work from inside out. Okay, let me know if you guys have any questions