Series Parallel Combination Circuit #19

alright guys let's do another series parallel circuit here so usually by the time you guys finish the 18 ones as I do in class there's always those who ask for additional circuits up until this point I haven't taken the time to do some additional circuits and I'm lazy so what I did was I just went online typed in series parallel circuits into the search engine and I came up with two really good resources so I'm going to put these in the comment section below so this circuit that I've grabbed was this one right here so this kind of dominates the that search engine there and you'll find that this circuit is used time and time again I believe these guys are the original people who put it out so electronics tutorials awesome site and this YouTube video below is really good at breaking down a separate circuit as well so what I've done is I've just taken this exact same circuit I have doubled the values everywhere so I've just seen taking the same circuit but change the ratio there and then if you need an additional circuit so go to their webpage go through the exact same circuit but with half the values there and they do a great job of breaking it down slowly it's actually right right here so they're going to break it down in a different fashion in that they'll show you are a or B and they're basically doing series parallel circuits with the same laws that we're going to be doing in this video okay in addition to that you may want to go to this gentleman's website Jesse Mason does an awesome video here on how to solve any series and parallel circuit problems he shows how to break the entire circuit down and then build a back up you can see that it's almost identical to the circuit that we're going to do as well so now you've got three different circuits you can work off of from this one video I will put the the links below before you start this okay so back of the circuit they were looking at her there where do you start here well remember that what you're going to do is you're going to take a look at the circuit and you're going to mark out where each of your parallel nodes are so wherever you find a parallel node you can mark it off with a different color okay so what I'm going to do is I'm just going to mark off each of the parallel nodes so we've got current flowing from the source going out we pause here just get a different different font so that quick you can actually see where the current is rocking hearing ever okay so I've decided to go with a 24 volt source and we'll go from one side of the source and we're just going to draw in the way that the current is flowing from one side of the source to the other now at this point right here once it goes through r1 that's a parallel junction right there because we can see here the current rocks in this direction and it goes down here towards r2 let's finish off that circuit here through our two because it looks like the current goes down here through r2 and then right back to the source so it looks like that source voltage of 24 volts is going to be across r1 and r2 there okay if we continue along in this direction then we're going to go through r3 okay so this is quite obvious but we're just going to take the time to show what other parallel nodes are okay and then we've got current that rocks in one tooth in four different directions looks like current goes through our eight and our ten so we've got a series circuit that we can deal with there it also goes through our nine here goes down through our six and then depending on the way you're looking at kind of rocks back here through r4 okay excellent so now we've got all of our currents through each of these other resistors and let's start on the right hand side and we'll just show again the parallel junctions where the current combines so current is going to combine here and looks like it's going to come back to the source it's going to go through our seven recombine with the current from our six there's another parallel junction where the currents are combining then that combined current is going through our five and the currents that we had going through r4 and r2 and the combination of everything from r5 they're all going to rock together right here so that the current going through r1 and the current coming back is going to be identical excellent okay so now we can see which way the currents are flowing from one side of the source to the other but it's still messed up I can't make heads or tails of this yet so what we're going to do is we're going to try and read drive and see if we can show exactly which ones are series combinations and which ones are parallel so we'll start with when we start with the outside circuit there being this current here looks like we got a resistor here r1 r3 r 8 R 10 R 7 and R 5 will start drawing that guy oh and then we can see where our 2 4 6 & 9 fit into the mix all right guys so the next thing is just to redraw this to try and figure out where the series and parallel combinations are because it's not readily apparent with this diagram above so let's start off by doing r1 r3 r 8 or 10 r7 and r5 now I've just drawn all those guys in I've gone from one side of the circuit back to the other side there's a million ways to do this but I'm just going to try this and see how it works out so let's try in each of these names here so we got r1 r3 r 8 r 10 then we've got our 7 and finally our 5 so I went from one side of the source to the other side now are these in series no they're not exactly in series and we're going to find out there are parallel combinations that combine with this one but let's just check off the guys that we've got so far and we'll see how the rest of the the circuit kind of plays into this now maybe we'll start off with our tuna because if we go from r1 to r2 we can get right back to the source so I'm just going to arbitrarily drop in r2 let's drop it in down here a little bit okay and hopefully that leaves us with enough room to throw in the rest of the resistors okay the next thing we got let's see we got all these guys right all the way around and we've now taken care of r2 we can see that r2 is in series with r1 there's a parallel node right here that corresponds to right here so now what do we need to take care of maybe our 9r9 seems to be in parallel with our eight and our ten right you can see there are nine is right across those two guys so our nine is going to go across our eight and our ten so let's just drop in a line here come across here and then tie into the other end of our 10 there excellent okay that takes care of this guy okay that looks good then what do we need we need our for our four looks like it's going from what this parallel junction right here to the the tail end of our three and then just going into the tail end of our two so from our tail end of our three to the tail end of our - okay well tail end of our three is right here right so we can drop in that resistor and we needed to line up with the back end of our - excellent okay well let's just bring this straight across and we can see that five five four and two are all tying together to the same spot excellent so this guy is our four now all we need to do we've taken care of this guy here the last thing we need to do is just bring in our six and it looks like we've got everything in one diagram so our last one being our f6 looks like it's going from the tail end of r3 and then it's also going in to the point between 5 & 7 so tail end of our three would be right here and somehow we need to throw in a resistor that would then go to the midpoint between our five and our seven well if I put it here then I'd have to be jumping over this line here so maybe we'll drive up here drop in that final resistor and then it has to tie into the midpoint between 5 & 7 and we said that guy was our six beautiful okay now we've taken care of all of the resistors in the circuit instead of being a confusing diagram like this one above hopefully this one's a little bit easier to work with and now we can see where the parallel combinations are and now we're going to slowly break down placing our source voltage across and we also have to break it down to our total resistance because we still don't know our total resistance for the circuit yet excellent all right guys so what I've done is I've just taken that diagram we just did moving it onto a blank sheet here growing it up a little bit so we can fit in all the values and I've placed in all the resistance values for each of these resistors now okay in addition to that maybe we want to throw in our supply voltage at 24 volts and we can also just make note of where we have these parallel connections where we've got current going in different directions and then coming back to recombine looks good another parallel connection here and then obviously everything's coming back over here back to the source excellent okay so now we got to figure out our total resistance for the entire circuit so what we're going to do is we're going to slowly break this down into an equivalent circuit by looking for series circuits break them down and then do parallel combinations as we go until finally we get our total resistance then we get our total current and we can kind of build the circuit back up and move through with our currents for the entire circuit ok so first thing we need to look for is any series combinations so let's see we've got our 1 and branches off our 3 then branches off our 6 is on its own 5 7 or on their own 9 4 on their own twos on its own the only ones that seem to be directly in series are our 8 and our 10 so we know that resistors in series are going to add together our h20 our 10 is 4 so we'll add those guys up to give us 24 ohms and and we'll just eliminate these guys so 8 and 10 and we're back down to 24 or for an equivalent resistance okay so we'll just draw that in there ok so we have our equivalent resistance for 8 and 10 because we put those those two guys together ok next thing we need to do is look for any parallel combination here so let's see let's take a look and see if we can find a parallel combination that we can bring together and we can seeing as most of them are just two resistors in parallel we can use product over some to find the equivalent value so let's do these guys let's do what we did with 8 and 10 the combination of those guys and let's do the combination of this resistor here and our 9 so we've got one value at 24 one value at 12 and those guys you can see are directly in parallel there so if we're looking for that equivalent resistance then we're going to have what 24 times 12 over 24 plus 12 okay so we'll do the product over some there let's say 24 times 12 is 288 and if we divide by that the addition of the other guys we got 36 so 288 divided by 36 gives us 8 ohms excellent nice round value okay so this one that we had for 8 and 10 and the combination with 9 is now going to be simplified down to an 8 ohm resistance so we're going to do is we're going to take away this guy because we found that equivalent resistance and we're now going to change this guy to an included resistance of 8 ohms yeah okay now that value is now in series with the 16 ohms so the next thing we can do is we can combine those guys in series so we can do our 7 and the equivalent value that we had here so 16 ohms plus the 8 gives us the value of what 24 ohms right so let's eliminate this bad boy right here the drawing connection here and now the combination of those resistors is now 24 ohms excellent okay let's keep going because it now it seems like our six and this equivalent resistance are now in parallel here so we can now do the equivalent resistance using product over some again we'll do 12 times 24 over 12 plus 24 okay the 12 12 times 24 gives us 288 now this looks exactly the same as before my friends okay then below we got wet 36 288 divided by 36 there's a trend that's happening is a domes excellent okay so our six and our combination resistance right here the equivalent resistance for those two guys is going to be 8 ohms so we can now eliminate our six okay and this value right now is 8 ohms nice okay that guy is now in series with r5 okay so we broken everything down here to one equivalent resistance of 8 ohms which is now in series with r5 so now we can eliminate r5 which was 8 ohms add that on to our urban resistance and now we got 16 ohms for that equivalent resistance value thanks right below that we've got another 16 ohms very nice those guys are in parallel and if we have two values of resistance that are exactly the same then the equivalent resistance is going to be in this case 16 ohms divided by the number of paths number of paths is two so again there's a definite trend to the circuit I'm liking it there's 8 ohms of resistance remaining there so r4 has now been eliminated okay and now we have an equivalent resistance of 8 ohms there that guy is in a saree in series with the 8 ohms for r3 so we're going to eliminate r3 note this guy is now 16 ohms recombine that and now it's apparent that the 16 ohms is in parallel with r2 which is also add 16 ohms go back to this guy equivalent resistance of 16 ohms divided by the two paths that are provided giving us a domes as a equivalent resistance so now we can eliminate r2 it's done and we're very close to finding our final answer here okay so we got a ohms for equivalent resistance for all the noise that we just eliminated and the last thing we do is we just combine r1 with our 8 ohms of a clip resistance and it looks like our total resistance is going to be 20 ohms very nice now we've got our total resistance now we rock and we can use that 24 volts and the 20 ohms in order to find our total current and let's just draw that in here so there's no questions excellent so total resistance of 20 ohms total voltage applied is 24 so now we can find the total current flowing in this circuit we got 24 volts we got 20 ohms of equivalent resistance excellent and so 24 divided by 20 gives us one point two amps for our total current going in and out of that circuit nice so now what we're going to do is we're going to bring that one point two amps and we're going to bring it into our initial drawing so we're going to build back up to that larger drawing now if you got lost as to where I came up with that 20 ohms then just stop the the video go back a little bit and just slowly walk through how we came up with that 20 ohms of total resistance okay so back to our original diagram we now know that there's 1.2 amps flowing in this circuit so we can draw in our 1.2 amps coming from the source and then going back to the source excellent okay that one point 2 amps is going to flow now through r1 so we know that through r1 we're going to have 1.2 ABS flowing there and that will provide us with our first voltage so 1.2 hips coming up here and that's going through r1 and obviously coming out of there we're also going to have 1.2 apps and then let's see I just our current times our resistance 1.2 times 12 is going to give us a voltage of 14 point 4 volts across that first resistor excellent okay now we go I won't put two amps and then we got to figure out let's see either a voltage or a current so let's see we've got our o1 and it looks like current goes in two directions goes over here to this combination of three six eight ten seven five nine and four and it also comes over here to r2 so it looks like the the 24 volts that's from the source is applied to this side of r1 and is also available over on this side of our - so the whole source voltage is applied across r1 and r2 so that means that this bolt is right here at our two would be the 24 volts which we've got for the source - the 14 point 4 volts so we got nine point 6 volts across r2 very nice now we're going to use that voltage and the resistance we're going to take the nine point six volts divided by 16 ohms that gives us 0.6 amps flowing and that portion of the circuit okay well we had 1.2 we took away point six and that leaves us with point six amps flowing in the remaining portion of the circuit if you go back a little bit on the video you would have found that the equivalent resistance of all of this was basically 16 right have the same resistance so same current is going to flow in each of these portions of the circus we got point six amps flowing here and coming out of that resistor again the same current beauty so now we got point six amps we've got to multiply that by 8 ohms and that gives us four point eight will across our three okay so now we can do the same thing initially we use the 24 volts as the supply for r1 and r2 because we have that path right across 24 now what we're going to do is we're going to use the the r2 with the 9.6 volts as the source because for e4 r3 and r4 if we follow from here that same voltage should be applied here at one side of our three and if we follow that voltage it's also available over here at our four so the voltage across R 3 and r4 should be nine point six well there's four point eight volts lost across our three and if we take that nine point six take away the four point eight well that leaves us with four point eight volts across our four okay so just like we had in similar in similar circuits and similar videos that we covered before this you can always use this as the supply for r1 and r2 then following that looks like an r2 is now the supply voltage that's being applied across r3 and r4 excellent so now we've got four point eight volts and we've got 16 ohms so we'll take the four point eight volts we'll divide it by the sixteen and that gives us point three amps that's flowing in this portion of the circuit UT we're working our way through finding most of the the voltages here now we just got to take a step back and take a look at the surging figure out what our next voltage is going to be or whether there's the same current flowing in another path well I I've looked at this for quite a while here and messed me up for quite a while trying to find here at the next step here so let's see this 4 point 8 volts that's here that's applied across our nine and across all this combination here so we can't really keep going with that same rule that we just said so maybe the currents are going to help us out let's draw in our currents here so we have 0.6 amps right here we have 0.3 amps in this rung we have a combination of 1.2 amps coming back so let's see we got 1 point 2 amps coming back looks like we have 0.9 apps for the combination of those other two portions of the circuit 1.2 minus 2.9 leaves us with 0.3 amps flowing in this portion of the circuit so it's not really the voltage at that point it's going to help us out with the rest of the circuit it looks like the current now that current if we compare it should be the same as the current on the remaining lines here which it is we have 0.6 going into this parallel node 0.3 coming down here leaving this with another point 3 amps that's going to flow through all of these guys and recombine here but this is awesome because now we know that the current here is 0.3 that means that the current flowing through our 5 is going to be 0.3 X U so now we got point 3 amps we're going to multiply that by the 8 ohms and across this guy we got 2 point 4 volts so hopefully that slowly helps us in determining maybe another voltage in the circuit there ok so pause the video again take a look see if that helps you out to find another portion of the circuit it's either the current flow or it's going to be using one of the resistors as a source voltage for the other guys let's see over here we still have all this noise over here so it's hard for me to see individual current flows there maybe we can look at the voltage let's use this guy this 4.8 now as the source voltage and that voltage is going to come up here and it's going to across our six and the other side of that four point eight volts is also going to be apparent right here so we got four point eight volts but we're going to lose two point four so that means that the remaining voltage across this guy right here across our six is going to be 2 point 4 volts because this voltage here has to match with this voltage here we've lost two point four leaving us with the remaining two point four volts across our six excellent okay that's going to help out now because now it's going to give us an additional current we have two point four volts we're going to divide it by the 12 ohms so we got point two amps flowing in that portion of the circuit nice now we're just down to two rungs are we have to find voltage values and an equivalent current value okay so we have point 2 amps flowing here we have point three apps flowing here and then we also have another point three coming here so this point three we lost point two amps so we need point one apps flowing in this final combination here so you could look at the the current and maybe the total resistance there to help you maybe we'll look at that I can't really see it let's maybe look at the voltage across R 8 R 10 and our seven so this 2 point 4 volts would be here at this Junction and that 2 point 4 volts is also across here at this Junction so the 2 point 4 volt is applied across each of these resistors R 8 r 10 and our seven and if we add up our 8 r 10 our seven we got we've got 24 plus another 16 that gives us 40 ohms and if we take the the 2.4 divided by that 40 ohms that's going to give us point zero six amps flowing in that portion the surrogate ok so now we've got that current remember that current is going to be coming right across right that is essentially a series circuit here so that identical current is going to go right across and that'll leave us with our voltage is there on our 8 10 and 7 so our 8 is going to be wet 20 ohms times the point zero six apps that's going to be one point two volts across this guy leave much room to regular voltages there ok next one we got at point zero six amps and we got four arms we're going to multiply that by 4 that gives us seven point zero six oh that's only 0.2 four volts across this guy nice and then finally we have point zero 6 r7 it is 16 ohms and that leaves us point point nine six across our seven a quick check is to add up the one point two plus the point 2 4 plus the 0.96 a beauty that gives us 2 point 4 volts so the combination of all these voltages here for 8 10 and 7 is matching with this voltage on 6 this diagram is getting pretty messy last one here we need our nine so let's see we can see that our nine is right across our eight and our 10 our 8 and our 10 have a voltage of one point two and point two four and if we add those guys up the remaining voltage is going to be one point four four volts across our nine very nice okay so let's see we had the 0.3 amps that was flowing here and we're going to subtract the point zero six amps that we have flowing in this portion of the circuit and then we're going to subtract the point 2 amps that's flowing in this portion of the circuit leaving us with point zero four zero point zero four ABS flowing through our nine let's just double-check if that works point zero four right amps times 12 ohms is given us point four eight and what I do there okay so that's no good that current there and that bolt that nothing's working out there with those values so it must have gone off the mercury let's see if we can go back a few steps and see where I went off the mark I made the assumption that that voltage of two point four volts was across our eight our 10 and our seven that gave me the point six amps but I didn't take into effect or into a camps right the fact that our nine is in parallel with our 10 and our seven so let's go back a little bit some of you guys already noticed this and we're losing it because the values that I was writing down on the page we're not matching yours I just wanted to show you a quick way that you can screw this up so I thought that the two point four volts was right across each of those resistors and sorry but in effect it wasn't so let's take a look one more time and see if you can find those values okay so that two point four volts is across here and here but we have to take into account that these guys are in parallel so we have the two point four volts but we need to find the equivalent resistance of these guys one more time so here we have 20 four volts in parallel with 12 ohms right so again if we go and do that product over some 24 times 12 is 288 divided by 36 that's 8 ohms so these guys right here the equivalent of 8 ohms plus the the 16 is 24 so really it's 2 point 4 volts across 24 ohms of resistance okay so that leaves us with 2 point 4 volts divided by 24 ohms of resistance that gives us 0.1 amp flowing through there okay so the the combination of these guys is going to be point 1 amp there will that make sense right because I we've got point 2 point 1 adding to give us the point 3 all right things are looking a little bit better ok let's see if it finally works out now okay so we got point 1 amps flowing there we're going to multiply that by the 16 ohms for our 7 that gives us 1 point 6 volts across our 7 nice okay so now what's our next step here we got the current there we got the voltage across our seven let's take a step back and see if we can just figure out our 8 9 and 10 ok well let's take a look at the the voltage we do have 2 point 4 volts from here to here right so that means that we should have 2 point 4 volts from the same point down here across to here so we've got 2 point 4 volts impressed across R 9 and r 7 and if we lose that that 1 point 6 then that leaves us with 0.8 volts across R 9 okay so these two currents the current through our nine and the currents through eight and ten have got a sum to give us Oh point one amps and then we can finish this on so we have point eight volts we're now going to divide by 12 ohms and there's point zero six six six repeating here okay so we got point zero six seven apps through that portion of the circuit okay so if we have point one apps over here and we've lost the point zero six seven through our nine the remaining current is going to be point zero three three through these guys all right so that point zero three three and the point zero six seven are going to sum to give us that point one and we can find our last two bullet is there so point zero three three amps times twenty ohms is going to give us Oh point six six volts across our eight and then finally they voltage across our 10 is going to be point zero three three times the four ohms gives us point one three two excellent and if we sum those guys together the point 1 3 2 and the point six six they should sum to give us point eight

Channel: Pete Vree

Views: 182,104

Rating: 4.6860671 out of 5

Keywords: series parallel circuits, series parallel combination circuits

Id: kfzyfxO3YR8

Length: 36min 56sec (2216 seconds)

Published: Wed Sep 07 2016