Electrical Engineering: Ch 4: Circuit Theorems (16 of 35) Thevenin's Theorem Ex. 1

[@annasarahkramerfazendeiro8030]

I am actually skipping class to see this video, to reduce the time needed for understanding and practicing the concept from +2 hours to 30 minutes. Once again a well made, carefully thought out tutorial by my favourite online professor! Keep up the great work, the world needs more engineers!

[@adriandurlej9266]

im IN class watching this video. Learning far faster then if i was paying attention lmao

[@nabzim]

How'd you end up doing in your class? (your grade=?)

[@esmirhodzic981]

couldnt have put it better myself :D ++++

[@chrisvincent782]

the world doesn't need more engineers. wait till you get out and can't get a job or gotta work for $15 for a greedy PE. I remember how optimistic i was b4 I graduated

[@jdextlab]

@@chrisvincent782the world always needs engineers. The seniors aren’t gonna be here forever

[@djomarkaram3609]

This guy is the most underrated professor of all times!!! He should be getting millions and millions of views because of the way he teaches! Thank you

[@qemmm11]

It is definitely 😊

[@clarkgriswold5842]

This is what I like, straight to the point and consistent. I wish my professor wouldn't side track every so often during lecture. May a statue be erected for your work.

[@jarettmulvaney977]

Wow, this is the first video I've seen by you, and in eight and a half minutes I learned more about Thevenin circuit analysis than I have in the past week and a half in my circuits class. You are a god-send! Thank You!

[@Boomshakalaga]

Sir you’re the best teacher I ve ever watched

[@MichelvanBiezen]

We appreciate the feedback. Glad you found our videos. 🙂

[@Boomshakalaga]

@@MichelvanBiezen i was studying circuit theory retakes and the way you solve is almost the same as our teacher. And I understand much easier here. Thanks again

[@MichelvanBiezen]

Great!

[@AjaySharma-dl7uy]

I am starting to fall in love with you !! Even the tutor I paid didn't teach so well.

[@MichelvanBiezen]

Thank you. Glad you like our videos.

[@mrch33sehed93]

Geez... you just helped me understand 6 hrs of lecture in 8 minutes 😯👍

[@MichelvanBiezen]

Glad we could help!

[@justinbryansantiago3923]

THE BEST TEACHER EVER! I wish you are my teacher. From Philippines btw thank you I love your tutorial videos sir!

[@kaankaraman9850]

I appreciate your help. I now learned. you look like e good prof. from now on I'm gonna watch your videos when I have something in my mind

[@MichelvanBiezen]

Glad to help

[@claudyfocan731]

I’m in my first year of mecanical engineering. My professor is a nuclear engineer (patents in multiple things, rich as fuck 🙄) so he teaches DC as a way to pass his time. He doesn’t give the slightest fuck about us, but this video finally made me understand it! Thank you sir! It’s not as hard as it looks. I love your videos! Greetings from Belgium 🇧🇪

[@shivamkapoor6590]

Im curious....How many degrees do you have? You literally teach all my uni courses! :)

[@y.z.6517]

And Michel van Biezen teaches them better than average professors in the best universities!

[@MA-qz1sd]

If you are smart enough you can teach anything. You teach yourself and then you teach it to others. Once you teach others it becomes easy to keep the information you learned.

[@michaelheryanto7555]

@@MA-qz1sd couldn't agree more with you ;)

[@it6647]

He even looks like Euler, definitely his reincarnation.

[@tempestandacomputer6951]

To be honest, an engineering curriculum covers most of his channel.

[@Safwan.Hossain]

4:32, the why is the voltage from the node equal to the voltage to the right of the 1-ohm resistor? Isn't there a voltage drop because of that resistor? Edit: nevermind didn't listen carefully enough, that part of the circuit is shorted so no current so same voltage through that line. I'll keep this comment up in case anyone else was confused.

[@MichelvanBiezen]

There can only be a voltage drop if there is a current through the 1 ohm resistor, and in this case there is not.

[@ldobs_]

best video out there about thevenin voltage! finally understand this !!!!!

[@johndczerwinski]

Very thorough explanation. I finally get the concept. Two question: 1 - I assume, in a practical sense, that once you solve for the Thevenin's equation, one can replace the RL with any value and the resulting current will hold true to the original model. 2 - Is there a good source of practice problems, with answers, to continuing sharpening my new skill?

[@مصعبامزين]

I’m really don’t know how to thanks you I was not know anything in this subject but after I watch your video i understand to you thank you 🙏🏼.

[@MichelvanBiezen]

Glad we could help!

[@JIMISPIER]

Best video on Thevenin's Theorem

[@MichelvanBiezen]

Thank you. Glad you found it helpful. 🙂

[@iftikharakhan1256]

Dear Professor, Thank you so much for your help. I am having trouble understanding why Vth at the node and across the terminal is similar. It would be really helpful if you can explain. Thank you so much for your time. Best, Iftikhar Khan

[@MichelvanBiezen]

+Iftikhar A khan When finding the Vth, the circuit between A and B is open, which means there is no current between Vth and A and thus there is no voltage rise or drop across that 1 ohm resistor.

[@jeffsonic]

very clear, state the rules, act according to the rules, you get the result. thank you

[@Dark_Peace]

All the other vidéos and my teacher failed to make me understand. But now I get it ! Thank you !

[@MichelvanBiezen]

Happy to help!

[@venkataramanaiaheluru1272]

Thank you very much sir, I am student from India Our electrical lecturer isn't able to explain this us properly.Your explanation is very amazing.....

[@MichelvanBiezen]

Welcome to the channel! We are glad you found us. 🙂

[@dr-mnizam]

Be patient when learning. Nobody is perfect. Here is my video kzbin.info/www/bejne/iKLTmq1slJiCi9k

[@kajalpandya7650]

Thank you for explaining this. Your method of teaching is really nice.

[@MA-qz1sd]

My teacher needs to watch your videos

[@mkonongo_og]

Under this concept I think every problem will be Easy to solve....thanks you so much Sir💪💪

[@motparts]

thank you, Michel ! I watched other videos about it and didn't find such a clear explanation as yours

[@footballnews1439]

You are doing the lords work

[@MichelvanBiezen]

Thank you. I like to think that both my wife and I are of service doing this work.

[@footballnews1439]

@@MichelvanBiezen I sincerely thank both of you

[@danieltambunan9717]

why ist 1 ohm is in paralell? generally, how to know resistor is in parallel or series, when it's open circuit like in 2:12 ?

[@ignacioalarcon661]

You are saving me through circuits sir

[@qemmm11]

Thanks Sir 😊 Rth=(4//12)+1=4 Eth=(32*(12/4+12))+(2*(12/(4+12))*4=24+6=30v(Superposition theorem) And then i=30/(4+5)=30/9A

[@dlrmfemilianolako8]

If in an example we have dependent current and voltage sources ( we must short these type of voltages ?)

[@MichelvanBiezen]

Current sources are removed and left open and voltage sources are replaced with a short.

[@Mikail-bjk]

Eyvallah başkan. Türkiyeden selamlar ✋🏽

[@MichelvanBiezen]

Thank you and welcome to the channel!

[@jehoshaphatsiame7525]

You sir, are amazing. Thank you so much you have helped me a lot

[@sultanalhammadi2910]

Hi Sir Did you remove R(load) because you want to get an open circuit and hence it would be equal to infinity? And what are the differences between R(load) and the other resistances. Finally, where did you assume is the ground? Thanks

[@mollys.8988]

Thank you - this really helped me understand!

[@Aqwtiny]

Why is there no current running through the 1-ohm resistor? I thought the 2 Amps will travel throughout or is it because of the resistance on the left side of the circuit much greater than the right that it's negligible?

[@MichelvanBiezen]

In order to have a current, you must have a closed circuit. With the load resistor removed, the current has no place to go, so you can't have any current through the 1 ohm resistor.

[@Aqwtiny]

@@MichelvanBiezen Oh man thank you so much , now I see how silly my question was.

[@MichelvanBiezen]

Not silly at all. Sometimes these types of things really trip us up and it helps to get it clarified.

[@barneywhite9293]

@@MichelvanBiezen How come when you calculate the Thevenin resistance though do you include the 1 ohm resistor? Is it due to the fact that a voltage will flow across it?

[@jeetenderkakkar7570]

a 230V 50hz ac supply is connected to a resistance 2.5ohm coil of inductance 0.06h and capacitor of 6.8uF connected in series. calculate impedance of circuit current phase difference between voltage & current

[@MichelvanBiezen]

We have a lot of example just like that in this playlist: PHYSICS 49 RCL CIRCUITS

[@brewertonpaul]

Brilliant stuff this.. now my tiny brain gets it! Thanks!

[@ayodejiolanrewaju9713]

thank you so much, it’s really helpful. I so love your page 😍.

[@MichelvanBiezen]

That is great to read.

[@amarealemnew7699]

my good teacher iam from ethiopia

[@MichelvanBiezen]

Welcome to the channel! 🙂

[@Gan-sx2br]

I like the way he stands in front of the board while he writes so it makes it extra hard to follow along.

[@yassirelaboudi8201]

Very nice! Thank you Pr. Van Biezen

[@curtpiazza1688]

Great treatment of this confusing topic! 😅

[@MichelvanBiezen]

Glad you liked it. 🙂

[@riftlive9051]

Thank you. It was a great explanation.

[@nchls5730]

Hello there just wondering if we can use Voltage divider to determine the Vthevenin? Thanks for your response.

[@MichelvanBiezen]

The voltage divider should work in almost every case.

[@fera5165]

Thank you Prof. Michel! Again.. :)

[@elicervantes8910]

Dear Professor, I am having trouble figuring out why the 4 and the 12-ohm resistor is in parallel, shouldn't the be in series ? Can you please explain? Thank you!

[@MichelvanBiezen]

When the current source is removed and the load resistor is removed, then there is only one current path and the 4 and 12 ohm resistor are then in series.

[@elicervantes8910]

Now, you're saying that the 4 and 12 ohm resistor are in series but in the video you say they are in parallel.

[@MichelvanBiezen]

Ah, now I understand you question. When finding the Thevenin resistance, you have to calculate the resistance relative to the terminals at the removed load resistor, and in THAT case the two resistors are in parallel.

[@elicervantes8910]

thank you ! now i get it

[@aniizuchukwustanley4066]

Sir why do you also said that current is not flowing in the 1ohm resistor?

[@aliciajender2270]

Sir can we use current divider to find the thevnin voltage ?

[@RexGalilae]

Since the 1 ohm resistor is good as nothing, how about we simply use the voltage division rule between the 12 & 4 ohm resistor to find Vth?

[@MichelvanBiezen]

It is better to learn the technique so you can learn to do more complex problems.

[@leoliCYL]

Hello Professor, I'm slightly confused why the node we were solving is V_TH, how does that node equal the voltage across the gap?

[@MichelvanBiezen]

If there is no current flow (due to the gap) then there is no voltage drop and the node voltage must equal the V_TH

[@AJ-et3vf]

Awesome video sir! Thank you!

[@MichelvanBiezen]

Looks like you are going through the whole playlist! 🙂

[@hannahcommons5556]

When using Kirchhoff's law to find Vth, why do we not say (Vth - 32)/12? As far as I understand, its always the difference of the two nodes on either side of the resistor, divided by the resistance, and the 12 ohm resistor is also connected to the 32V and Vth.

[@MichelvanBiezen]

You must always express everything in terms of an equation, and since (Vth - 32)/12 is not an equation, I cannot answer your question.

[@AAAAAA-es1rm]

Dear Mr. van Biezen, What are the main advantages of using the Thevenin's Theorem over source transformations to answer the example you illustrate in your video ? Thank you.

[@MichelvanBiezen]

Ultimately it comes down to what you prefer. Here we are just showing the different methods so you can become familiar with them.

[@iftikharakhan1256]

Thank you so much Professor for your explanation. It would be extremely helpful if you can show an example with a dependent voltage or current source. Thank you so much!

[@MichelvanBiezen]

+Iftikhar A khan Good point. I'll have to add a few examples with dependent sources.

[@MrYounis26]

Shouldn't you add the 4 and 1 in series and then calculate with the 12 in parallel? Would that be incorrect.

[@MichelvanBiezen]

That would be incorrect. Try it and see if you get the same answer.

[@MrYounis26]

Michel van Biezen Different results, however I saw some videos doing that way, I'm not sure why, and others doing your way too.

[@fxjeda6894]

Question: on using kvl for solving for the current across the first mesh, the vth turns out to be 36v. Please could you help me with an explanation or perhaps a correction for this paradox. Thank you so much for all you've explained. You have really assisted me in my academics.

[@MichelvanBiezen]

I didn't quite follow your question. Are you saying the if you take the original circuit and solve for the voltage across the load resistor, you find it to be 36 V and you wonder why it doesn't equal the V th? They are not supposed to be the same since the V th is found without the load resistor.

[@fxjeda6894]

@@MichelvanBiezen No sir. I followed all your steps prior to when you used the nodal analysis, in which place i used kvl. The answer then varied

[@MichelvanBiezen]

It is easy to make a little mistake anywhere during the solution of the problem. (I do that too often myself). If no mistakes were made, the solution should be the same.

[@fxjeda6894]

Thank you sir, I'll need to brush up on elementary math then.... lol 😅

[@GaugeSymm]

This might be an obvious question but lets say I don't have a current source in a branch but instead I am given that 'A 'amp of current flows, then would the source transformation still work? ( IT should I suppose, but I could be wrong, I am a student of class 12th and electrical circuit problems are my weakness)

[@MichelvanBiezen]

I would try Kirchhoff's rules.

[@Sfundo_Ndlovu]

Good day Mr van Biezen, I would like to ask how do you know that the voltage is the same between the two nodes?

[@MichelvanBiezen]

Not sure which 2 nodes you are referring to, but if it is the two nodes at the top, there is no component between the two nodes, therefore there cannot be a voltage drop and there is no current througn the 1 ohm resistor so there is no voltage drop there either.

[@Sfundo_Ndlovu]

@@MichelvanBiezen thanks Sir

[@eliacoldwar-us9qr]

What it both voltage and current source are at the edge of the circuit and the load is in the middle of the circuit???

[@MichelvanBiezen]

Then I suggest you redraw the circuit such that the load is at the edge.

[@KITRishabh]

To find thevinin resistance both independent and dependent source must be removed or only independent source should be removed?

[@sahilghanchi8064]

Plz make video on theory 😞

[@TuberKMT]

Very good. Thank you! Just a little lost why VTH = V at open terminals.

[@mohamadred7640]

perfect explaination

[@MichelvanBiezen]

Thank you. Glad you found it helpful.

[@zouhairelhadri6907]

Dear Professor, Are we looking the circuit from the right when we shorted the voltage and cut off the current source to find the R thevenin ? because i do not know why the 1ohm resistance is not remooved or we do consider it when finding the Rth ?

[@MichelvanBiezen]

We are always looking at the circuit from the perspective of the "load" or load resistor.

[@fisherofmen489]

Why are 4ohms and 12ohms in parallel but in the equivalent circuit 4 and 5 are in series, when to me at least they have the same configuration?

[@MichelvanBiezen]

Since the current moving from left to right through the 4 ohm resistor does not have to go through the 12 ohm resistor, but can also go through another branch, they are therefore not in series. In the equivalent circuit ALL of the current flowing through the 4 ohm resistor MUST also flow through the 5 ohm resistor (there is no alternative path) and therefore they are in series.

[@sehreshtariq3266]

thankyou so much :D this has been really helpful to me

[@paramveersingh8285]

Sir i was trying this question in a different way. I followed the steps for example but rather than doing nodal analysis I used source transformations to simplify the circuit. However I didn't manage to get to a final answer. Could you try this question using source transformation pls and get back to me? Because i believe this method should work too.

[@MichelvanBiezen]

Yes, source transformation should work. Most of these circuit problems can be solved using any of the methods presented. (some are more easily solved with one method versus another). That said, it is very easy to make a single mistake somewhere which will throw off your final answer.

[@priyankak6748]

Hi sir, I have one doubt. vth is the voltage across the terminals A and B. In Equivalent circuit we connect the resistor series to the vth. in equivalent circuit the voltage across the terminals A and B is not equal to Vth because some voltage drop present across the Rth . so in equivalent circuit the voltage value across the A and B is not equal to vth. am I right or wrong sir .Please clarify my doubt sir. Thanks in advance:)

[@dude84says]

Thank you for making this video, it saved my arse from getting F for my test

[@zmh27]

How do I know where the load resistor is? if it isn't stated in the circuit?

[@MichelvanBiezen]

The "load resistor" is a placeholder for any portion of a circuit that is attached to a pair of terminals. The "load resistor" can be a resitor - inductor or resister - capacitor, or resistor - capacitor - inductor combination or an entire portion of a circuit. For example exercises like this the location of the load resistor must be indicated, otherwise there would not be any way of knowing where it is placed.

[@jnie98]

Sir, how can I know that the Voltage drop is (32-Vth)/4 but not (Vth-32)/4?

[@MichelvanBiezen]

We are making the assumption that 32V is a higher potential than Vth because we assume the direction of I1 is from left to right in the circuit.

[@stephaniecurry45]

@@MichelvanBiezen yep, my professor just assumes current is leaving so the node we're dealing with always appears first in the calculation of voltage dropped.

[@obentabiayuk4780]

please which text do you recommend for circuit analysis. you're such a great teacher

[@MichelvanBiezen]

We can't really endorse any texts. There are many good ones available.

[@anaotsuka6939]

It helped a lot thanks!!!!

[@MichelvanBiezen]

Glad it helped!

[@eliacoldwar-us9qr]

Which means where ever you find a current source you leave it open

[@MichelvanBiezen]

With the application of Thevenin's theory, yes.

[@DocHolidayKY99]

can't i use source transformation to change the current source into another voltage source?

[@marcoli262]

So why no current flow through the 1-ohm resistor?

[@MichelvanBiezen]

Once the load resistor is removed (RL), the brach now has an open and current can only flow if there is a continuous circuit.

[@ryanmeoni1483]

Why is there no current through the 1 ohm resistor? In the very next example video in this series, you have a nearly identical circuit and you're tasked with finding the current through that portion.

[@MichelvanBiezen]

When the load resistor is removed, there is then no closed loop and thus there cannot be any current through the 1 ohm resistor.

[@ryanmeoni1483]

@@MichelvanBiezen Makes sense. Thanks.

[@karanh]

why is no current flows in 1ohm ?

[@MichelvanBiezen]

Unless that circuit is connected no current can flow through the part of the circuit that is not a complete loop.

[@mahendrareddysura9010]

Why u multiply 12 in node analysis

[@shruthipasala5326]

Sir, can u plz explain me that, how did u take voltage at the node as Vth? thank u Sir

[@MichelvanBiezen]

Since there is no current through the 1 ohm resistor, there is no voltage drop between the node and the point to the right of the 1 ohm resistor. Thus the node must be at the same potential as Vth

[@shruthipasala5326]

Tnk u Sir. I got it.

[@bildozarcapo377]

Hello sir Can you apply the current and voltage in this case Thank you

[@ranexia04]

Dear professor, thank you for the video! One question though, why is Vth at the node equal to Vth at the open cable?? What about the "node"(dunno what else to call it), right above the current source?

[@MichelvanBiezen]

Because there is no current flowing through the 1 ohm resistor and there is no resistor between the node and the 1 ohm resistor (no voltage drop).

[@whar1]

It says to remove current sources and short voltage sources, but didn't you short the current source and remove the voltage source in the example?

[@MichelvanBiezen]

To find the Thevenin Resistance you must indeed remove the current source and short the voltage source, which is what was done in the video.

[@ersinortagenc5233]

what does short voltage source mean?

[@kittykitkat7348]

Hi professor, why did you does the voltage through the 4ohm resistor = 32 - Vth ?

[@MichelvanBiezen]

Using Ohm's law: I = V/R to find I1 we need to find the current through the 4 Ohm resistor. The voltage drop = 32 V - V at the node (V at the node in this case = Vth)

[@sithembisothukoane4415]

Good day Professor Why does current not go through the 1 ohm resistor

[@tempestandacomputer6951]

Because it is an open circuit at the end A. Because current needs a closed path, current does not flow in the direction of A and therefore does not flow through the 1ohm resistor.

[@samsuzzaman1717]

i can not find the series and paralal connection properly.can you help me to solve the problem dear professor?if you make a class lecture on this topic then it may be very helpful for myself.

[@MichelvanBiezen]

You can find some videos here: PHYSICS 41.1 RESISTORS IN PARALLEL BRANCHES

[@samsuzzaman1717]

Thank you very much..sir

[@edenadam3593]

🙏🙏🙏 👌👌👌 👍👍👍 Thank you very much Sir!!!

[@jacobphong7972]

Dear Sir, how do you determine the direction of the current flow of I1? why is it clockwise instead of anticlockwise?

[@MichelvanBiezen]

Sometimes it is obvious as the (conventional) current flows from the positive terminal to the negative terminal. It can also be determined using Kirchhoff's rules. And if you are not sure, you can "assume" a direction. If the direction is wrong, you'll end up with negative answers for the current thus it doesn't matter, your answer will then tell you the correct direction

[@jacobphong7972]

@@MichelvanBiezen Thank you very much for your reply

[@aydinjavadov4331]

Professor, how do we determine the directions of I1, I2 and I3?

[@MichelvanBiezen]

You take a guess, and then work with those guesses. if you guessed wrong, you'll get a negative answer for the current.

[@stephaniecurry45]

@@MichelvanBiezen my professor for node voltage analysis tells us to assume all currents are leaving an essential node and to treat leaving as positive and vice versa for entering

[@j4908]

How do you know if the resistances are in series or parallel please?

[@MichelvanBiezen]

If the current (going from A to B) must go through both resistors, then they are in series. But when the current goes from A to B and has a choice to go through one or the other, they are in parallel.

[@j4908]

Many thanks, Professor!!

[@biseraciric454]

@@MichelvanBiezen Oh my God, thank you so much for this "tip"... You are the best!

[@ชายจากดวงดาว]

could someone please explain to me,why there is no current flow to that end where 1-ohm resistance is at. I did search some but still don't really get it. I know that it is an open circuit. but the current does not flow toward that end at all tho?

[@MichelvanBiezen]

Any branch that does not form a complete closed loop will have zero current flow.

[@ชายจากดวงดาว]

Michel van Biezen thank you so much sir

[@aniizuchukwustanley4066]

👌

[@Jptoutant]

Thanks for the great lecture

[@MichelvanBiezen]

You are welcome.

[@samuelpokluda2772]

Why doesn't the voltage divider equation not work. As in why isn't the voltage drop on the 12 ohm resistor equal R thev?

[@MichelvanBiezen]

The voltage drop across the 12 ohm resistor is indeed equal to V th

[@samuelpokluda2772]

@@MichelvanBiezen so I must be using the wrong R total, (12/Rt)*32 = 30 so Rt must be 12.8 but how do you get 12.8 for R total??

[@enggeraldetudi-uk6xh]

His explanations were okay but the challenge I faced was of a board not being clear.

[@MichelvanBiezen]

We just checked the video, and it was recorded in high definition. However since there is so much information crammed onto a single board it was designed to be watched from a computer.

[@rustamshahverdiyev4164]

Sir, how can we determine whether this circuit linear or not ?

[@DocHolidayKY99]

i believe this means that it's a circuit with no wires moving above/under each other. where in the figure it would look like a little bump.

[@MahdiJalilzadeh2001]

Thank you. Very usefull

[@MichelvanBiezen]

You are welcome. 🙂

[@makkitson]

Dear sir, Could you tell me how can i find the RL using by thevenin's theorem. ??

[@MichelvanBiezen]

The load resistor is not "found" but should be a given in the problem.

[@blatogh1277]

This is so good

[@aleph_eight]

Sir can I use superposition theorem to fiend Vth

[@MichelvanBiezen]

Usually, multiple methods will work on the same circuit. We show the different methods, but ultimately, you will use the one you like the most.

[@subhendumandal1865]

sir how i increase knowledge in network theorem..?plz tell me

[@MyThundermuffin]

Thank you for this tutorial