Okay, and welcome to advanced circuit analysis. This is Al from Al's electronic classroom. And I suggest that if when you take this course you need to do one of two things. One, take in my previous circuit analysis course or have a fundamental understanding of circuit analysis, okay because we're going into some advanced subjects here, and you need to have a background. So what we're going to cover in this first section is Kurt chops laws. kerchief was a physicist did a lot of exploration or A lot of studying on electronics back in, I think it was the late 1800s.

And he came out with some laws, which we're going to talk about current Trump's current law, Voltage Law, some of the methods that he used to diagnose current flow and the value of components on the air being what we have here, method of branch currents, node voltage analysis, methods of mesh currents. And then on this last part here, we we kind of look at a circuit and apply some of the laws that we've studied so we can get the values of resistors or currents in a branch and so forth. If you don't know what I mean by that. That's fine. We're going to cover that as we go on to the next slides. So here we go.

We're going to go on, see on the next slide. All right, the first law that we're going to talk about about here is Kurt chops current law. And if you look over here in this little resistor network that I've have, I've got basically I show you three currents. Okay ay ay ay ay ay ay ay ay. ay b. And I see.

All right, let's look at this first equation where kerchief talks about his current law, what he's saying is I've got if I have currents, and we'll say that's a node. If I have currents going into the node, and I subtract the current leaving the node, it should be zero. Right there. So if you look, we've got three amps here, and five amps. They're flowing into that node. I have eight amps.

Coming out of the node. So if I add them up, they should be zero. Another way that we can say it, and you'll probably hear, hear it this way. Now, current that flows into the node, or the total amount of current that flows into the node equals a current that flows out of the node and that, that sounds a little bit better, but this is how he kind of described it back then, probably over 100 years ago. And today, we say current into the node equals the current out of a note. It kind of makes a little bit more sense, but we're saying the same thing.

So right here, if you look at it I've got is three amps. IB is five amps. I add them out. add them up. It's eight amps. So current flowing in his gut equal current flowing out.

It has to it's natural force, it has to work that way. All right, you can't leave current on the side of the road. I mean, it's got what goes in is gonna come out. Hi. Nuff said on that. Let's go on to the next slide.

All right, the next slot we want to talk about is card shops, Voltage Law right there. And what he states is voltage or ground, a closed loop must equal zero. And I've given you this example here, and basically, we've got three loops here. We've got a loop here, a loop here, and then we have an outer loop. All right, all three of those loops. When I go around a when I make one complete revolution.

The algebraic sum of the voltages around those loops has to equal zero. So let's go on to the next slide here. Let's move on. We're going to go to the next slide. And what I've done is I've gone through and calculated the voltage drops across each one of these resistors. For instance, our five is two volts DC.

Our six is five volts DC. Our two is one volt DC r four is two and a half volts DC and so forth. So r three is 1.5. So I've gone through and I've calculated them I didn't take the time and going through through here to do them. This was presented online My previous circuit analysis course, I showed you how to do that. So, if you're a little bit shaky on how we got these voltages, you can either retake the course that my, my advanced my circuit analysis course or you can bone up on on the material that you already have, you can do your own investigation online or whatever, but you should be pretty well comfortable on how I got these voltages.

Okay. All right. So let's, let's move on. And here we're going to, we're going to talk about loop one, which is this loop here. Alright, that's loop one. So first we got two volts DC plus five volts DC plus five volts DC, plus 12 volts my a plus a minus 12 volts.

So what we're doing here is we're starting here at that point here, and we're going clockwise. Alright, so we're going this way. So if you look, here's my plus, plus two volts DC. We don't show the plus there, but it's assumed to be plus. Then the next one is this plus right there. And it's five volts DC.

And we come around here, here's the other plus right there. That's also five volts DC. And we got a plus minus right there of 12 volts DC. When I when I add that goes up, they equal zero. So my first loop is zero volts as I go around the first loop and measure the voltages algebraically. All right, let me stop here and clear off the side slide and we're going to do loop two.

Okay, we're doing loop two here. And again, we're going to start at this point there. And we're coming down. So what do I hit right here, a plus five volts DC right there. Then I'm going to add a minus 1.5 volts DC there. Then I'm going to add a minus 2.5 volts DC there.

And then I'm going to add a another minus one volt DC here and again, Again, when I do all when I do my math and I add them all up, what do I get? zero volts DC. All right. Okay, let me clear the slide off and we'll do the third one. All right. We're going to start off right here.

And we're doing the loop three, which is the outer loop. All right, and what do we hit first right there, a minus five volts DC plus a minus 1.5 volts DC plus or minus 2.5 volts DC plus a minus one volt DC plus a minus Two volts DC right there, plus 12 volts DC right there. And again, if I add all if I add the algebraic sum of those voltages, it should be zero. Now a couple of things I want to mention, before we move on here is I pick the points where I started arbitrarily. Okay. You can pick any point in the loop and start.

You can go clockwise, you can go counterclockwise, just you what you need to do is observe the polarity of the components and it should work out. All right. What, on this example here, there's three loops. So if I get zero in all three loops, I've, I've done my calculations properly as far as the voltage drops. If I know the voltage drop across the resistor, then I can solve a current flow and so forth. But are we always going to do this?

Probably not. It's, it's, it's a way to get give you a feel for what's going on. So you can intuitively look at something and say, okay, that's got to be this value resistor. All right. So if you do enough of these, you can intuitively see what the value is. You can see if it's good or bad, and other words your calculations are correct or not.

All right. So take this for what it's worth. It used to be I was employed with with someone and he says just add it to your bag of tricks. All right. I mean, are we going to use this all the time? No.

Be aware of it and put it in your bag of tricks. Okay, with that said, let's move on to the next slide.