Complex Numbers: AC Circuit Application

[@Cu_Ty_Pro]

I HAVE TO SAY THIS IN CAPITAL, TO EXPRESS MY FEELING ABOUT HOW THANKFUL I AM TO YOU, AND YOUR EXCELLENT JOB OF EXPLAINING HOW TO GET THE Z IMPEDANCE AND ITS PHASOR ANGLE. THANK YOU SO SO MUCH ! IT IS A VERY EASY CONCEPT, BUT I HAVE BEEN LOOKING AROUND ON THE INTERNET FOR HOURS, JUST TO UNDERSTAND HOW THEY COULD COME UP WITH THE NUMBER + THE J , AND A PHASOR ANGLE AFTER. THE VIDEO MY INSTRUCTOR SHOWS TO GET THIS IS RATHER LONG AND COMPLICATED. YOUR VIDEO, IN CONTRAST, IS SUPER NEAT, SUPER CLEAN, SUPER EASY TO COMPREHEND. THANKS A MILLION !

[@pablogimenez8369]

In an inductors, voltage leads the current by 90 degrees. Or the current lags the voltage by 90 degrees. The opposite is true for a capacitor.

[@16ndimngqo]

I came here for this.

[@honey2opgaming502]

Exactly ki bhi bol rahi ye.

[@Nshiime]

Can I just say that you have literally saved my life.very wonderful simple explanation.Thank you so much

[@thinkfirst6374]

I guess you have graduated hows it now?

[@sunilgokhale612]

At point 3.03 when you drew graph and explained lead lag concept, the current in the circuit leads voltage across the capacitor and lags the voltage across the inductor.. You said it other way I think.

[@larrybadgett7648]

Z is a complex number. The resister is the real part. The Inductor minus the capacitor are the imaginary part.

[@amramjose]

No, the complex number is the magnitude Z and the angle/direction, theta or whatever letter you like. Your second sentence makes no sense at all; maybe you mean to say their impedance, respectively, are complex numbers.

[@tiagotoledo2996]

There`s, still, a grave mistake. Repeating what has been already comented by Bunnyy 83: "The correction is also wrong ^^. As said the graph is actually right but what is said is wrong. Inductive loads --> current lags voltage and not voltage lags current. If you reverse the two things the "lags" becomes a "leads". So indeed the voltage does lead the current since the current lags the voltage. Just as "A > B" is the same as "B < A"" Thank you for the video!

[@inoffensiveusername4684]

I was so confused when I heard that and read the correction lol... I was like uhh Inductive reactance leads by 90 degrees?>.>

[@renusahu707]

GUYS READ MY COMMENT.. cause there is nothing like complex method in this video.. Complex method is another method which makes AC calculations very easy...TY

[@WordlessAmrit]

excuse me ,,,,,in pure inductive circuit current is lagging by 90 degree,,,,amn't i right?????

[@qasimpakistan]

+Amrit koirala Yeah, I think there was a mistake. Inductive: Current lags voltage. Capacitive: Current leads voltage.

[@edgerrr]

Yes, at the 3:00 mark, they show the VL and VC phase shifts backwards. ICE...current leads voltage in a capacitor ELI...voltage leads current in an inductor

[@RRCWiseguys]

+Taan- Dav In circuits with primarily inductive loads, current lags the voltage. In capacitive circuits, current leads the voltage. This is exactly what is said in the video. Upon review, I have discovered that the visuals don't align with the correct statement in the video. Annotations have been added to this video to clear up confusion. Thank you for bringing this to my attention!

[@Wayk123]

This is so oversimplified you might aswell not use complex numbers. Would be really nice to know how we got to them and how is eulers formula used...

[@bloody1ify]

That was freakin awesome.. At the beginning of this circuits 102 course the prof said that complex numbers have no use and they can be solved by calculator, next lecture he threw at us R-L-C circuit and ofc we understood nothing because we had no background in complex numbers!

[@rodericksibelius8472]

This is Analysis in the FREQUENCY Domain using Phasors, which was innovated by Charles Proteus Steinmetz, an Electrical Engineer, it is much easier than solving / calculating in the Time Domain.

[@Mir6922]

Best video ever... I cant possibly thank you enough. Please keep going.

[@jagmarc]

A great application is for impedance matching networks, such as pi T L . Goes well with Smith chart

[@CutinChai]

excellent video but only thing missing is the complex number by adding angle for L & C in your calculation for Z.

[@fivosteren1382]

Excuse me, I'm not implying that i know more , but doesn't in time 2.50 the voltage in an inductor leads the current by 90 degrees and in time 2.59 the voltage in a capacitor lags the current by 90 degrees?

[@DfromBoston]

That is correct!

[@26ohms99]

at 2:58 in Inductor the correct is V leads I by 90 degrees or I lags V by 90 degrees not V lags I by 90. Same with Capacitor it's also incorrect, in capacitor I leads V by 90 degrees or V lags I by 90 degrees not V leads I by 90 degrees.

[@GlowingGlare]

Thank you for a clear way of describing this method.

[@bassemadonoo1112]

I love how you teach , it's easy to understand. But the wave aspect is incorrect, you gave the inductive circuit the properties of the capacitive circuit rather and vise versa .thank you.

[@RRCWiseguys]

I ended this video by saying I could not solve more, because I did not have current. Which, upon reflection, was incorrect. I could have solved for current and solved for all voltages... However, my focus for the video was solving for reactance and impedance so I chose not to solve the entire circuit. Upcoming videos will have entire circuits solved.

[@shimuanis7015]

she just wanted to show "how much the impedence is"......................

[@aleksandarsavic7659]

+Red River College Wise Guys There are many components to learning circuits. One plan I discovered which succeeds in merging these is the Gregs Electro Blog (check it out on google) without a doubt the most useful info i've seen. Check out this unbelievable website.

[@tobes9074]

Thanks so much for taking the time to make this video for us all! Just a quick question, is your final answer equivalent to the mathematical expression z=46.57(cos(15')+isin(15')? Thankyou!

[@FireVortex720]

+PaleBlueDot Yes that is polar form - the same thing.

[@eye2eyeerigavo777]

Matching the cicuit is the idea behind this... Where applied? Think about coaxial cable design and how its impedance calculated for Matching cicuit.... Great job done...

[@noelatilano2739]

how about if you have parrallel combination with series and you were ask to find the impedance of the circuit shown ? can you make an example of that. thanks to this video. I find it easy to solve this way

[@tillifindu]

Thanks for the video, just a query, when we say that voltage lags in inductance, does it not imply that the graph is shifted to the right. And similarly for lagging, the graph should be shifted to the left. Am i wrong ?

[@RRCWiseguys]

+Madhusudhan M Sharma You are exactly correct. This is what is said in the video. Upon review, I have discovered that the visuals don't align with the correct statement in the video. Annotations have been added to this video to clear up confusion. Thank you for bringing this to my attention!

[@albertpicher832]

Thank you. Excellent video.

[@manoharping]

Sorry Madam, For an AC Circuit In case of Inductor Voltage leads the current by 90° means current is lagging the Voltage by 90° and In case of Capacitor Voltage lags the Current by 90° it means Current is leading the Voltage by 90°.

[@saeedou]

thank you so much for this useful video . and i finally find out the different between Z an R and its the angle .

[@maxrybold1531]

I like your video format and explanation. Thank you so much!

[@kemalm9383]

Is it the same in non-polarized capacitance.

[@sophadyvorn8678]

Where can I check my exercise right or wrong about circuit I has done.?

[@eren3942]

You saved my life.

[@dipanjondwari4773]

Mam. we know that the resistance is +ve real in a R-L-C network so the Impedance can have angle -90 to + 90 . But what happen if in a calculation of Impedance there is quantity like (-3+j4) ? what to do should I take |5| angle 126.86 degree ? kindly reply please.

[@leitaylor6042]

For capacitor the current should lead voltage by 90degrees.But in the video in capacitor voltage leads current by 90?

[@jennifersiagian]

thank you for good teaching (I wish my mind can receive it) but I will on trying.. Math is the Creators language I want to know..

[@imtiazahmedimon9557]

Great video!!

[@richardwhalen1859]

Great video

[@hamiltoncarlos5695]

Obrigado professora pela aula.

[@Jason-ot6jv]

That was a brave round up to 15

[@Shiva68]

Wow really great explanation …

[@sudhirpatil3434]

I liked way madam taught... making things simple!!

[@abhishekparasnis6148]

can u tell me why reactance is taken as imaginary??

[@TANUJKUMARPandey9999]

Its a very big error ,Voltage always leads the current for purely inductive circuits by pi/2 (or 90 degrees). If this will not happen the inductor will not be able to store the energy as magnetic field. If voltage lags the current the element will behave as capacitor.

[@TANUJKUMARPandey9999]

Although the graph you are using shows voltage leading the current for inductor 😂

[@squarepusher303]

Great video, thanks!

[@charlyg120]

congratulations... what a good explanation

[@g00glian0]

Wow. Best explanation ever!

[@boburyuldashov7419]

Great video! more???

[@doom_field]

What does the angle represent? in other words, why is it important?

[@ardiris2715]

What happened to the complex numbers?

[@sandmastermaster]

I would re upload the video because of that mistake

[@ianfischer8813]

Do Americans really use the Zig Zag as an symbol for the resistance? In europe we use a rectangle

[@georgiosantaras7773]

what is the angle equal to , help

[@kiera__willow7660]

I AM DOING A 13 PAGE PHISICS THING ON CIRCUITS THAT WE HAVEN'T LERNT YET THANNNNKKKKYYYOOOOUYYYY FOR MAKING THINGS CLEAR🙏🙏🙏

[@allthegearnoidea6752]

Great video thank you

[@johncarlvaldez54]

Thank you ma'am its help a lot 🙏😊

[@Cinqmil]

2:57 You make a grave mistake here. *In circuits with primarily inductive loads, current lags the voltage.* *In capacitive circuits, current will be leading the voltage.* Videos like yours make it unnecessary hard for students to understand the basics. Please correct the error or remove the video.

[@Bunny99s]

+Cinqmil Yes i found the same mistake. For me it seems like a strange approach to base the graphs on the current. The voltage cause current, not the other way round. A voltage is a state / potential like pressure in a pipe. If the pressure is high enough to overcome the resistance a current will start to flow. If you have inductivities the current lags behind the voltage by 90°. They have a high resistance in the beginning and a lower resistance once "loaded". Capacities on the other hand have a very low (almost zero) resistance in the beginning (--> results in high current) which get higher the more "loaded" the capacitor gets (--> the current goes down). I just want to point out that the actual graphs in the video are correct, but the interpretation seems strange. The graph represents a timeline. Things which are more to the left happened earlier than things to the right. So for example VL is at max at time "0" but the current lags behind. The current reaches it's max 90° later than the voltage. I'm sorry if i didn't use the right terms. I learned all that 15 years ago in my native language (german) so i have some difficulties translating everything correctly ^^.

[@RRCWiseguys]

+Cinqmil In circuits with primarily inductive loads, current lags the voltage. In capacitive circuits, current leads the voltage. This is exactly what is said in the video. Upon review, I have discovered that the visuals don't align with the correct statement in the video. Annotations have been added to this video to clear up confusion. Thank you for bringing this to my attention!

[@Bunny99s]

+Red River College Wise Guys The correction is also wrong ^^. As said the graph is actually right but what is said is wrong. Inductive loads --> current lags voltage and not voltage lags current. If you reverse the two things the "lags" becomes a "leads". So indeed the voltage does lead the current since the current lags the voltage. Just as "A > B" is the same as "B < A"

[@bauyrzhankokanov5498]

Cinqmil it's not wrong she took it in respect to Current. It works actually both way around, depends how u visualise. Sometimes is good to think out of the box/or templates, the principles are the same

[@blondul07]

i tought something's wrong in her reprezentation. I KNEW THAT IN CAP THE CURENT IS AHEAD CUZ THE CAP'S CHARGING UP, AND IN INDUCTANCE, VOLTAGE IS AHEAD OF CURRENT CUZ INDUCTANCE OPOSES THE CHANGE IN CURENT ( WICH COMES FROM THE FREQ.)

[@FredoCorleone]

what's the difference between lagging 2PI and leading PI?

[@BLUFFIRL]

lagging/leading 2pi is the same as lagging/leading zero since 2pi is a full cycle, lagging/leading pi is half a cycle

[@FredoCorleone]

So there's no matter in the waveform! :)

[@BLUFFIRL]

depends what you're asking, the amplitude and frequency will be the same no matter what the offset is, an offset of pi will cause a half cycle offset, an offset of 2pi does nothing

[@FredoCorleone]

my question was wrong ahah I just realized, I meant what's the difference between +PI/2 and -PI/2... and 0 and PI... I mean, what's the evaluable difference, will the signal has some delay arriving or just phase difference?

[@melbourneopera]

how do one add Ztotal = Z1 + Z2 = R1 (Angle 50) + R2 (Angle -70)???

[@engineerSalih]

You are using the wrong analogy here... instead of saying " component react differently to current" you should say " component react differently to VOLTAGE" the current we get is caused by the reaction of the components to the voltage, not the other way around. Here is an example, We apply a voltage ( which is an independent phenomenon from the components), THEN, we get a current either lagging or leading to the voltage we applied. Why would the current lead or lag? Because of the reaction of capacitance or the inductance ... Voltage comes first ( Cause), then come the current ( effect).

[@TheTheRunecape]

If you take 120V divided 46.57ohms you will end up with 2.576Amps

[@reginaldoar-jio9413]

thanks!

[@reeldud3]

very well explianed

[@train4905]

Awsome😊😊

[@-wheeling9509]

Helpful granma !

[@nilanjandasTV]

Thank you ma'am 💗

[@poorneshpavansai5140]

THANK YOU SO MUCH MAM.

[@sohailjanjua123]

Hi, I like your lecture

[@unitedelectrician4334]

Great video Nice job

[@TheStrelok7]

Nice Explanation!

[@بوفارسبونورا-ص7ه]

Where is Euler's equation ? !!!

[@sandeepkushwaha3389]

Thanks❤

[@shilpimitra5342]

Voltage across inductor should lead

[@shikharbind4883]

This is not the compex number method....this is phasor diagram method....complex number method is used to make the calculations faster. & Calculations are done in eular form So please don't use wrong captions to bring attention....Its complete waste of time

[@DulceSeeker]

you have the XL and XC upside down then its not making sense what is lagging and leading bad bad bad!!!

[@moiz6164]

Current lag by 90 degree.....in inductor circuit..........please check

[@Vladferrum]

Am I the only one who felt pain about the ring on the left hand?

[@mmukulkhedekar4752]

um, that's not actually the application of complex numbers, it's just some phasor analysis. you just plotted a bunch of stuff on argand plane. should've shown how complex numbers make some work easier dealing with complicated ac circuits

[@sunilmandal7191]

It was good but for inductor voltage leads and current lags whereas you have said reversed ! For capacitors voltage lags and current leads ! That also was told reversed !!

[@Ceylonish]

This helped so much , (Y)

[@dhruvinvekariya975]

error 404-complex no.s not found

[@maliktaufiqurrehman]

she made mistake at 3:00. in explaining leads and lags of voltage and current.

[@spencerpruitt1437]

Thanks for the video. You went very, very slow though.

[@BankruptGreek]

doesn't help that our teacher bases current to voltage and not the other way around :/

[@2011Thesituation]

this video help but i had to wait 8:20 lol thank u

[@arpitkumarbaranwal3093]

complex no?????

[@chrisb178]

+Arpit kumar baranwal R+jXL-jXC

[@Seedhe_Maut]

Where is complex number j

[@sayakmaity4106]

zindagi jhand kar di

[@Natrem7]

you dıdnt find current you should do V=I.Z

[@sisekosmith9548]

This video is filled to the brim with mistakes.

[@pavanim5335]

Pavani

[@pavanim5335]

Super

[@shashu1999]

1. Voltage in inductor leads by 90 degrees. 2. At 9:56 arctan is NEVER called tan to the -1. tan to the -1 is cot. 3. Too slow

[@martind2520]

arctan is absolutely called tan^-1, that is extremely common phrasing and consistent is mathematical function notation.

[@shashu1999]

Cool then

[@decimalnorth6592]

this video should be removed and re-explained correctly

[@delbertthelion]

too many mistakes

[@saugatpandey447]

Rubbish

[@Атом-ю3ж]

можешь на русском говорить?