Classification of Electrical Elements: Active, Passive, Linear & Network vs Circuit Basics

Unacademy, let's crack it. Unacademy, let's crack it. Hello and a very good evening to all my dear engineers, a

very, very warm welcome to Unacademy and Engineers Ki Pathshala. This is Ranjan. And today, in Basic Electrical

Engineering, you have already seen today's topic in the thumbnail. Classification of Electrical Elements,

we have already started Module Number One. So, we are going to study it in a great way. I hope you all are full of

energy and are completely ready to prepare your notes. Okay? So, everyone has arrived. Let's start the session.

Let's begin. I am Gaming. Connected with us. Very good, man. Very good evening, my dear Adarsh. Very good

evening, dear Manoj. And to all the students connected, a very, very good evening to you all and welcome to this

session. So, let's get started. Then what is the delay for? Is the audio and video all okay? Shall we continue? Tell

me quickly once. Army Lover, greetings. Dear Deepak, Rohit, Sudipta, a very, very good evening to all the students.

Where is yesterday's video? Adarsh has asked. Go to the channel. Go to the channel. Engineers Ki Pathshala, go to

the live segments in that. You will see it there. You might be looking for it in the videos. It wouldn't be visible

there. Right? Once you check in the live segments particularly, you will see it there. Even then, if it's not

visible, you can tell me. So, shall we continue? Hello dear, very good evening , Apoorva. Shalini, Priyadarshini,

Vinay. Okay. Okay. Okay. So, let's continue. Guru ji. Hello dear. Okay. Will Civil classes also start? They

will start gradually. Usha has written, "I am weak in circuits, sir." I told you, right, that this is going to be a

past status now. The present has to change, it's the past. Now, it will be a thing of the past that you are weak.

Let's continue. So, what are we going to study today? How are we going to study? I have already explained the

syllabus introduction in yesterday's video. If you haven't watched it, take some time and make sure to watch it.

The future plan will become clear to you regarding how we are going to approach it. Okay? For now, we will

begin Module Number One here. So, from today, your writing part and your note-taking part will become strong.

Along with that, you will have to do one more task, that at the end of this session, I will show you some questions

from different universities. Take a close look at those questions and tell me whether or not you will be able to

solve them after studying everything we covered. All right? Let's get started. Right? Is it the same for BTU

University? Right? Patna Pirates Fan Page has asked this. So, you should definitely watch yesterday's video once

. I have explained the entire syllabus discussion university-wise. Follow that once, and you will get an idea about it

. The timing of the session is very important right now. So, I will quickly take you directly through the content

at this time. Let's take a look at today's topic and see what and how we will study it. Our topic for today is,

first of all, we are starting Module One. Right? This is Module One. Now, it is the beginning of Module One. All

right? What are we going to study in this Module One? Let me tell you once again. So, in this, we are studying

Basic Concepts and DC Networks or you can call it DC Circuits. All right? This is going to be our topic. Right? I

have already given you the details of this. This is the chapter name, and all the topics are inside it. I showed you

the full list of topics in a mixed-up form yesterday. Today, I will show you that list once again, and we are going

to study according to that. So, in this Oh, "I am Gaming" has written that, " Sir, this module is not in our college

syllabus." Check your AKTU syllabus carefully once again. It will be under the name DC Networks or DC Circuits.

The chance of this module not being in Basic Electrical is very low. It is definitely there. And it is in AKTU,

why? I can say this because I have specifically looked at AKTU University's syllabus. And another

great thing is that today I also have your university's question paper with me. All right? So, we will look at that

too. I will show you a glimpse of the question paper regarding the topic we are studying today. Just keep studying

carefully. So, what are we going to study in this? Let me give you a small idea about it. All right? Is everyone

ready to plug it up? You don't have to plug it up like that. All right? You don't have to plug up engineering like

that. I mean, Basic Electrical. All right? You have to plug it up well. So, let's see what we have to study today.

Overall, our chapter deals with these things. Basic concepts of electrical engineering. The entire portion of

basic concepts plus DC networks is here . And what all do we have to study in this? Look. Introduction to electrical

circuits. Concept of voltage, current, power, and energy. Right? What are the various elements of an electrical

circuit? RLC, ideal and practical voltage sources, and current sources; I have slightly altered the sequence. I

will discuss some basic forms with you first. Okay? So, I have placed the classification of elements first. Along

with this, I will discuss ideal and practical voltage and current sources with you. Then, after that, the

elements and then the rest of the things. We will proceed in this sequence. Okay? Let's go. So now Hey,

there is no such thing as a silly question, man. Feel free to ask. Right? Why are we all available here? Ask

freely. There is no tension. Right? I am game. Every question is a good question. No problem at all. Okay? I

won't say that your question hurt me. Right? Remember? Let's go. So, basic concepts of electrical engineering.

Where will we start from in this? We will start now. First of all, the very first question that comes to your mind.

Now, many teachers will write "DC Networks" here. Some teachers will write "DC Circuits" here. The first

question that comes to a student's mind —a first-year student—is: "Sir, I see in some videos someone writes '

Electrical DC Network'." In some videos , I see someone writing "Electrical DC Circuit." Which one is actually correct

? I don't understand. It's very confusing. Okay. No problem. There is no issue. Okay. Thank you so much,

Priyadarshini. Thank you so much, man. Thank you so much. So, the very first doubt is: what is the basic difference

between a network and a circuit? It starts right from here. Network and Circuit. Okay, the first question for

you all. Are these two the same? If not . Then which of these is the elementary part? Is network an elementary term, or

is circuit an elementary term? Okay? Let's understand this first. Okay? My name is Ranjan. You can also call me

Ranjan Rai or RR Sir. You can also call me Ranjan Rai Sir. Okay? Yes. So, okay. So, the very first question that comes

to mind on day one when faculty writes on the board in the classroom, or when a professor writes on the board saying

"DC Networks" or "DC Circuits," or you are watching a teacher on YouTube and it says "DC Circuits." You are studying

in class and the teacher has written " DC Networks." The first confusion is, man, what is this "network" and "

circuit"? What is the difference between the two? Are they the same, or do we use these terms interchangeably?

Use the names. No, there is a slight difference. That is why there are two separate terms, right? If they were the

same, we would use just one term. First , let's see what a circuit is. Let's first look at the circuit. Okay? The AU

Patna syllabus will be completed. RJA has written it. Right? I have the AU Patna question paper with me today as

well. Definitely, that syllabus is also followed. I will show you at the end, but first, let me quickly teach you the

content. Don't go anywhere at the end because I will have you solve the question paper. The topic I teach today

is the same one that is in your university's question paper. Okay? So, we will see that at the end. Let's go.

Let's see, what is a circuit, brother? So, I asked you a question, which of the two is the elementary part? Is the

network elementary, or is the circuit elementary? The answer to this question is that the circuit is basically the

elementary part. The circuit is basically an elementary part. How? Look . It is a closed path. It is a closed

path formed by electrical elements through which current can be transferred through which the current

can be transferred. Okay? We will understand this now. I am just writing it down for you right now. We will

understand. What is a network? If this is a circuit, then is a network not like this? Let's write, a network is an

interconnection of one or more circuits which may be closed or open. So, the network has a wider range compared to

the circuit. Right? The network is a wider range. Prabhakar has written, is this lecture related to Mahajan? Sir,

Prabhakar, we are studying in a very detailed manner here. It is basically targeted for the university, and for a

student preparing for competitive exams as well, if you want to study everything in full length at the core

level, only then it will be beneficial for you. Because what happens is, for any examination, when you study for the

first time, you have to read it in full detail in core form. If you have already studied like that, then this

will not be useful for you. But if you haven't read it like that, then before going for shortcuts, you must have the

full-length core material with notes. Right? So for that, yes, it is. You can study from this. But let me tell you in

advance that the time here is 80 hours. Meaning its syllabus is 80 hours long. Which is fine for semesters. But if you

are speaking from a competitive exam point of view, then go through it selectively. That means as much as you

feel, "Sir, I have a doubt in this point." Suppose you have a doubt in AC. Right? Or if you have a doubt in the

network part, then watch those in full length. The rest, which you are already clear about, you can keep revising in

short. Right? You have this option. Right? Yes. So Asha wrote "all network" . Manish. The better you keep your

concepts clear, the better you will be able to guide children in the teaching field. Right? So the best way you keep

things clear, the best way you will guide the coming generations. So it is important, it is good. Okay? So now

let's see what a network is. Suppose we draw a network of this kind here. Okay? Let's suppose you have to identify and

tell which of the two is a network and which is a circuit. Look carefully. Let us suppose there is a resistor placed

here like this. R An inductor is connected. Okay? There is another resistor here. There is a supply source

here and it is open. While here, a resistor is connected. Another resistor is connected. A supply source and

suppose a capacitor is connected here. 10 Volts, 2 Ohms, 3 Ohms. 6 Farads. This is open between A and B. This is 2

Ohm, 3 Henry, 2 Ohm, 6 What. Okay? Now I have these two diagrams. One is diagram A. This is diagram B. Which one

of these is a network? Think and tell me according to you. Which of these two circuits is representing a network?

Tell me quickly once. Where have I drawn the network and on which one have I drawn the circuit? The elementary one

is the circuit. Dear, elementary circuit. The first one is a network and the second one is a circuit. 'I Am

Gaming' has written, okay. First is network, second is circuit. The first one is a network, great. A is network,

Umesh has also written that. B is circuit, okay. Priya wrote, A is network, okay. Ashu, A is network, B is

circuit, okay. You can definitely give it, Khan Sahab, definitely, absolutely, right, you can definitely give it. So,

Abhiman, definitely dear. So now see, what did we say about what a network is ? Interconnection, a mutual connection

between many different circuit elements and components, connecting them to each other. Right? Also, what else does its

definition say? That it can be a combination of different circuits, and these circuits can be closed, these

circuits can also be open, it's possible. Right? Like it is open from here, but still this is a network, it

is still a network. Option A that I wrote is a network. Why? Because it fulfills all the definitions of a

network. How? Look, there is an interconnection of various elements. Yes. It is made from a combination of

circuits. Yes, it definitely is. And it can be closed as well as open. So it is open too. There is also a closed part.

There is also some open part. Okay. The portion at the bottom, this is a circuit. Why is it a circuit? This is a

circuit. Why is this a circuit? There is a simple reason. It is possible for it to be a circuit, which is why we can

call it a circuit. Because this is a closed path through which a current can be transferred. You can send current

through it from here. Right? So that is why this is a circuit. It is a closed part. It might come to your mind, sir,

there is also an open circuit. There is also a short circuit. There is also an open circuit. Again, if there is an

open circuit portion, you can consider it a network. So when you study the chapter DC Networks, if someone gives

you the chapter name DC Networks, then it is a generalized form. So if you derive a short statement from this, can

you say this? All circuits are networks but all networks cannot be necessarily Assume it to be a circuit. Okay? The

vice-versa phenomenon cannot be applied to this. So, every circuit must necessarily be a network. It is fixed.

But it is not necessary that every network will be a circuit. This portion is not a circuit. But this portion is a

circuit. So, a circuit is a closed path formed by electrical elements through which current can necessarily flow.

This point is absolutely correct. But there is this difference. Okay? Hello dear. Yes. The one below is a circuit.

Right? Babar has written it. Absolutely correct. Now, the formation of a mesh will emerge from the circuit. Right?

Absolutely correct. We will discuss this further ahead. All circuits are networks, but all networks may or may

not be a circuit. Okay? So, Rame Bhai SV NIT has asked, sir, where will we get the notes? I will keep these notes

saved as a PDF. I will gradually send them to you in the group that will be formed for you all. Okay? So your notes

will remain perfectly safe. I will gradually send these notes to you in PDF format later on. But until then,

please keep making notes of this in your copies properly. Let's move on. So now we have understood the basic

difference between a circuit and a network. Okay? Is it clear to everyone up to here? Should we move to the next

topic after this? Rahul wrote, sir, what is the difference between both? Look, I just told you the difference

between both. Every circuit will be a closed path. It will necessarily be a closed path through which current can

be transferred. You can send current. But a network is not necessarily closed . It can be both closed and open. You

are not sending any current from here. Meaning, no current is flowing in this portion from this place. Okay? Current

is flowing in this one. So, this can be known as a network. Or if you look at the interconnection of multiple

circuits, that is also a network. So if I have three such small circuits. Right ? Suppose there are three such circuits

. This is one circuit. This is one circuit. And there is such a circuit. These three are circuits. Okay? Now, if

I interconnect them with each other, it can become a network. It is possible. If I connect this from here. Right? If

I connect this point like this. If I connect this point like this. Then a network can be formed from here.

Individually they are a circuit, completely they are a network. They form a network. Okay? Yes.

So that was one portion. Now moving on to the next. Now we talk about elements , which elements are there? In

electrical. We study about many types of elements. Resistor, inductor, capacitor, then diodes, if you go into

electronics, diodes etc., start appearing. So now, all elements have a particular classification as well. Yes.

Why do we need to study this? It is important in both places. Questions appear in university exams. Short mark

questions or short note questions are definitely asked from this. The second thing is, where else is it important?

If you are competing in competitive exams at the JE level, Junior Engineer level, questions have been seen from

this. Okay? And moving forward, whatever definitions you study, whatever network theorems you study,

these same words will be used within the limitations of all those theorems. So that's why it is necessary to study

this. Okay? So let's start. Next topic classification. Classification of electrical elements. In how many forms

do we classify electrical elements? Right? Let's take you to the slides for a bit. Let's look at it quickly. Rahul,

the network isn't clear? I will explain it again once. Okay? Look at it once again. Look again Rahul, the difference

between a network and a circuit is that a circuit has to be a closed path. Look , if it is a circuit, then it is

compulsorily a closed path through which you can send current. Watch, watch carefully. Understand the circuit

and the network will start becoming clear on its own. See, like here is a 2 -ohm resistance. Here is a 5-ohm

resistance. Here is a voltage source of 5 volts and suppose there is an inductor here. Right? It is a closed

path. When you connect this supply source through this, the flow of current will happen through it. This is

a closed path. This is what? This is a closed path. A closed path formed by electrical elements through which

current can be sent. This is a mandatory term within it. What is a network here? Now suppose, suppose I

redraw this entire thing here. Okay? This same thing. Along with this, I connect one more segment. Like this.

Okay. And I connect another segment with this. Now what do you see? Now look, this entire portion was a circuit

. This entire portion was also a circuit. Circuit number two. This is circuit one. These are all closed paths

. Current will flow through them. But will current flow from here? Will any current go through this portion? No

current will go through this. Why? If you even apply Thevenin's, you take the voltage value here as zero. If you

apply Thevenin's theorem, you will take the voltage value at these points as zero. No potential will be found here.

Whatever is found will be found right here. Okay? Then your VTH will be calculated. Suppose you have to reach

VTH here. Anyway, if you look at this entire portion, there is no compulsion for current to flow. If I combine this

entire segment, then this whole segment will be a network. What definition of network did I provide? Interconnection

of circuits. See, two circuits are interconnected with each other. It is a network. Now both things can happen.

Both things can happen. It is possible it was closed, then what would you call it? Even then, it is a network. It is

possible it remained open as it was before. Even then, it is a network. In a network, it is not compulsory that it

must be closed. So sir, can we call this a network? Yes. Absolutely. This is also a network. Or a circuit? And

the entire diagram that I drew is only a network. If I talk about the complete diagram, it will only be called a

network. When you look at the elementary portions inside it, then you can say yes, there are two small

circuits formed within this network. Otherwise, in its complete form, you will say that this is only a network.

Okay? So, a combination of various circuits which can be open or closed. You will completely call it a network.

If I remove this element from here or remove that element, it will no longer remain a circuit, but even then, we

will call it a network. A connection or interconnection of elements; it's not necessary for current to flow or not,

it doesn't matter. It will still be called a network. Right? That is the reason behind this. Yes. All right.

Let's move on. So, is the point clear to everyone so far? Now let me take you to the next topic. That is the

classification of electrical elements. Okay? That is the classification of electrical elements. Let's start. Let's

first look at the basic classification part of electrical elements. Vishnu sir has also joined us. Very good evening,

sir. Vishnu Sir has played a very important role in the planning for Electrical and the first year. Plus,

you must have also seen many of his videos on this channel. You must have followed the electrical videos. Right?

So, you are going to get to study many subjects from him in a fun way. Alright , so now let's move forward.

Classification of electrical elements. Yes. So, I was showing you the slide of the classification of electrical

elements. Let's bring up the slide. Which elements do you need to study in the classification of electrical

elements? Okay? Let me give you a quick review. Active element, passive element , linear, non-linear, unilateral,

bilateral, lumped, and distributed—if you understand these eight types of element classifications, your first

two-mark university exam question will be a sure shot. Your first two-mark or four-mark question will definitely be a

sure shot. Okay? Let's see. So, active, passive, linear, non-linear, unilateral , bilateral, lumped, and distributed.

We will also discuss examples of all of them as we go. Let's start with the active elements. Let's start from the

very beginning. First. Active elements. Active elements mean all those elements that provide their energy to the system

. Right? Now, active elements are those which can provide energy to the system. Those that have the capability to

provide their own energy to any system, any circuit, or any network. Those elements are known as active elements.

Like, you have to give its example. Right? Come on, you have to give its example. I will quickly have you write

down its definition. Active elements. The electrical elements. The electrical elements which provide. Energy to the

system. Or network are known as. Are known as. Active. Elements. Okay? What will be its examples? Active elements

which are themselves a source. Source of energy. There is a contradictory part at one point here. I will tell you

where. Let's understand this first. Okay? Okay? Voltage source, current source, Tanmay has written. Shalini has

written, "Sir, can we also call active elements an active network?" Look, when will a network be formed? When you

connect those active elements. Right? When you connect it, the network will become active. Otherwise, I will tell

you its example too. And there is a passive network. Passive network where there are elements like resistors. If

there is no source inside it, it will automatically be called a passive network. Yes. So, a battery is an

active element. The Warrior of Green Soul has written, sir, how will we get the notes? For notes, for now, just

keep noting them down along with me. If something gets missed, there is nothing to worry about. This PDF will be saved

with me. Gradually, later on, the group that will be there, right? I will send these notes to you in that group. Okay?

So, there is absolutely nothing to worry about. Yes. So, think and tell me some examples of this. An active

element is one that provides energy, which is a source of energy. So, I will write down some basic examples from my

side. Like a battery, or cell— whatever you want to call it—or a generator. Okay, think about one thing

and tell me. Does a solar panel or solar cell fall under the active category or the passive one? Think and

answer. Okay? I am talking about silicon-based solar cells. BJT, FET, MOSFET, cell, battery, current source,

voltage source—Shagun has written. Great, okay. Ankur has written, sir, how long will the class last? The class

timing is up to 9:30. So, currently, you are in the starting phase. Slowly, you will get conditioned to this time.

Then we will speed up a little. Right now you are at the basics, so we are studying everything at a relaxed pace.

Then, gradually, we will keep speeding up. And in this duration, we will study more content at a faster pace. Okay?

Anyway, yes dear, the playlist will definitely be created. Look, Vishnu sir has also told you, and the playlist

will definitely be there. So, you can follow through that. You will get all the lectures in sequence. Okay? So,

there is nothing to worry about. So come on, battery, generators—tell me quickly if a solar cell will be an

example of this or not? I am asking you this question. Will you write solar cells as an example of this or not?

Okay? Think and tell me. Let me take you to the second element. Next is passive element. Okay? The next point

is passive elements. Let's see. So, what do we mean by passive elements? Which elements are these? So, we

understand from the name itself, like active were sources of energy that provided energy themselves. Passive is

just the opposite. Those which do not have any energy of their own. Those which do not have any energy of their

own. Okay? They consume the existing energy from the system itself. Okay? Yes dear Srimant, the playlist will be

there. It will surely be there. Okay? No need to worry. Focus on this for now . So, passive elements which Let me

write it down. Those electrical elements which consume energy from the circuit in any form are known as are

known as passive elements. For example, quickly tell me some examples. The example department is yours, right? I

will tell you at the end, but you tell me first. It will clarify how well you have understood things. Okay? If you

cannot tell, I am here to tell you at the end anyway. So, Yes, batteries provide energy. Okay Shraddha, it is

definitely there. For the first-year basic electrical syllabus, you must watch yesterday's session. If you have

doubts regarding the syllabus, I have explained it in detail in yesterday's session. The first session is an

introduction to Basic Electrical Engineering. In that, all your doubts related to the syllabus will be cleared

. You can match it with your university syllabus to see how much of that content is useful for you. Okay? So now

, Sangram asked, sir, is a capacitor an active element? Watch the answer to this question carefully. I am going to

write the name of the capacitor here in this space. First I will write resistor , then inductor, then capacitor. So, as

Sangram asked, the question will surely come to your mind: sir, you said the capacitor is passive, but we have

studied that when supplied, if the capacitor charges in the first half-cycle, it also discharges in the

second half-cycle. Right? Now, if it is discharging in the second half-cycle, it is giving energy to the system. So

it should be active, sir. Right? Why did you list it under passive? Brother, if it is storing energy in the first

half-cycle, that's fine; it means it can store electrical energy in the form of charges or any other form of energy.

Okay? So now it is storing energy in the form of charges. In the second half , it is returning the energy,

discharging back in the form of charges . So, will it still be passive? Absolutely yes. It will still be a

passive element. Okay? Any source or any element that cannot generate and provide its own energy will all fall

under the category of passive. Two questions arise from this. Which two questions that have also been asked in

competitive exams? Right? Yes Prabhakar , that is absolutely correct. Hello Divyanshu, thank you so much dear. You

are in the third semester now. Nice. So okay. So here, resistors, inductors, and capacitors will all come under its

examples. We will talk about these two in detail. In fact, I will talk about all three when I explain the elements

we are going to study in the next class . I will tell you about all the elements in detail. Alright? We will

see their entire construction, working, parameters, and their classifications there. So basically, just keep in mind

that a capacitor does not have energy of its own. Meaning, it’s like if we borrow car keys from a friend and drive

their car to take our other friends for a ride, at the end of the day, that car is not ours. It belongs to our friend.

Alright? You cannot claim that, oh man, this is my car. No, you just borrowed it for a while from someone else. It is

someone else's car. Alright? The situation with a capacitor is the same. It has someone else's energy or someone

else's charge that it borrowed for a little while. It gave the supply to the circuit, and it has nothing of its own.

Okay? You can understand it in this way . Alright? Inder Singh. Hello dear, nice buddy. Thank you so much, my dear.

Thank you so much. So you can understand it like this. That is why it falls into the passive category. This

one and the inductor fellow too. Right? The energy they store is not their own either. It is borrowed energy. And

don't even talk about the resistor. Right? It doesn't care at all. You give it anything. It will definitely cause

power dissipation. Right? In the form of Vrms*Irms or I²RT, this fellow provides Joule's law of heating. So,

heating occurs in the circuit because of them. These guys are still decent, poor things. Because of them, XL and XC

come into play. What do reactances and reactances do? They never create such heating. Because they don't cause

active power dissipation at all. These are components of reactive power. We will study this later on. Do not be

afraid of this. Come, I will explain everything about this. So, we have arrived at active and passive now.

Let's talk about the next element. All these elements are like friends. We will keep talking about them now.

Alright? So, active and passive are done. Now let's talk about linear elements. Linear elements. Which ones

are they, brother? First of all, what does linear element mean? Let's understand this. Is a linear element

actually linear? Does it start moving in a straight line? No. Because of that element, the VI characteristic for that

circuit or that particular element becomes constant. Right? It becomes one passing through the origin. Okay? The

condition V proportional to I starts happening here. Is that okay, Akanksha? Yes dear, the circuits part, the

network theorems part, and everything related to BEE, that is Basic Electrical, I will deal with all of it

with you. Okay? Solar cell is active. Wow, that's great! Yes. So Adipreet Vlogs wrote that, "Sir, please clarify

about solar cells." So I asked a question. You guys asked me back the same thing. Okay? It can generate. In

which category would you place a silicon-based solar cell? Right? That is my question. Remind me at the end of

the session. I will definitely explain it clearly. Until then, you have time to think. Linear element. Those

electrical elements. Which. Follow Ohm's law. Or. Exhibit. A constant. VI characteristic. Are known as. Linear

elements. I wrote this in simple language. Now let me explain it to you in a slightly more complex way. But

this will give you more material to write in university exams. Understand carefully. Let's first look at the easy

part. PK Science Classes wrote, "Sir, how to clear the backlog in BEE?" Please tell me. I think that regarding

the backlog, you have a few months ' time until the examination. If you have time, just keep watching these sessions

. Your backlog will be cleared very easily. I will also keep mentioning which content is important for you

according to your specific university. How to study what, and it won't just be selective study; you will have a

thorough study. So it is bound to be cleared. Okay? So stay completely tension-free. If, if you have the time.

Okay? Yes. So, those electrical elements which follow Ohm's law or exhibit a constant VI characteristic

are known as linear elements. Right? I mean, what kind of VI characteristic? The VI characteristic that will be

formed there due to the presence of that element will look like this. Passing through the origin. It will be

like this. Okay? Let's suppose IV characteristics, or VI characteristics. It will be constant. Meaning V = I*R,

as we normally see in Ohm's Law, or the form where V is proportional to I. Right? That's how it is. We normally

read this much about linearity. But if you go a little deeper into it, you will see that linearity, the linearity

that we define for any element as linear, is basically formed by combining two properties. Which two

properties? The principle of homogeneity and the principle of additivity. Right? So, if you combine

the Law of Additivity and the Law of Homogeneity, the Law of Linearity is formed. How? Let's see that. This was

an easy way to write it. This is a normal, general definition. You will see every other student writing this

same definition. Is there any other way to define it besides this? Yes. There is another way. Let's understand. Look,

you can write that linearity is also given as a combination of homogeneity and and additivity. Now, a new problem

has arisen. You will say, "Sir, until now we were just figuring out linearity .""You have brought two new problems

into our lives: what are these homogeneity and additivity?" Okay. Let's solve this problem. Okay. Okay.

Okay. Okay. PK Science wrote that "Sir, we are from RGPV University.""Do you know, Sir?" Okay dear. Okay. That's

great. Right? I Am Gaming wrote, "Sir, please explain linear again.""Please, Sir, I didn't understand." There is

absolutely no need to worry. I am just taking you a little deeper. Then we will come back to the surface level.

Okay? Let's see. Linearity is also given as a combination of homogeneity and additivity. How will we understand

this, Sir? Let's see. Let's understand this through a circuit. Maybe this will help you understand. I am drawing a

circuit. Okay? Let's draw two elements here. Let's draw two elements here. Come on, one here, one there. Okay? I

will change its color because I am going to represent this in the form of some other element. Let us suppose I

have a circuit. I am providing excitation at one point in this circuit . Students who have studied Reciprocity

Theorem will be able to relate. Those who haven't studied it, there is no need to worry. Okay? I will explain it

right here. Suppose in this circuit, this element of mine is a source. It is providing energy to the system. Right?

And this over here is a passive element . It could be anything. RLC, it doesn't matter what it is. It is a passive

element. Here we are going to look at the circuit's response. Okay? So, I have provided an excitation, let's say

E1 T. Let's assume I provided the excitation in the form of EMF voltage. And because of this, there must be some

response here. I1 T Alright. What will I call this? This is the response. Now, it will depend on the magnitude of the

element. According to that, there will be some response. Okay? So, if suppose I say that here the excitation is E1T,

and the response is I1 T. Later, after some time, just listen carefully, after some time if I multiply it by alpha,

like this, I multiply it by alpha. Okay ? Then two things will happen. This was case one. Now look at case two. In case

two, what did I do? I provided alpha E1 T. I changed the excitation. I added some alpha to it. So now two things can

happen. Two things will happen from here. What? Which two things? Either the response will be equal to alpha i1

The response is also changing, or the response will not be equal to alpha i1 Both things, so if it is the first case

response, then you will say this circuit is showing the law of homogeneity. This circuit is

homogeneous. This circuit is showing a law of it is showing homogeneity. And if such a response comes,

non-homogeneous, it's not homogeneous, this circuit then. Okay? Yes Adarsh, absolutely, absolutely. January means

enough time, it will be done easily. Absolutely sir, absolutely dear. It's a series, right? You are from

Mangalayatan University, right? Yes, Yes dear. Okay, so remember this point very well, you guys. Okay, everyone,

keep this point in mind clearly. So PK Science Classes wrote that this time the channel name is correct. Whose idea

was this, sir? This is Dhande sir and Gurpal sir's idea. Okay? It was their idea what the name of this channel

should be and I think it is absolutely correct now. So let's proceed, what will happen now? So this is the concept

of homogeneity. So, if its response is changing by the same amount in exchange for this excitation. It is following

the principle of homogeneity. That is absolutely correct. And on the other hand, how is the property of additivity

shown, brother? Homogeneity. Okay? Now let's check its second property. Additivity. How will the property of

additivity be identified? Suppose. Now, if I provide an excitation E1T to this same circuit, what response do I get?

I1T, okay. Again, I provide an excitation by changing some value to E2T, I changed some voltage. Earlier I

was giving 5 volts, now I am giving 10 volts. So the response I get in return, let's assume it is I2T. So suppose I

add both of them. Addition. Okay? What did I add? E1T + E2T, I added these. So what could be its response? Now there

could be two types of responses for this. Okay? Now this circuit can have two responses. Which two responses? The

first response could be equal to I1 + I2T, the second response not equal to I1. + I2T. So if the first response is

coming from the circuit, if you get this first response then it is showing. Additive property. This was the

in-depth form of understanding linearity. I will explain it to you again in an out-of-depth form. Meaning,

I will explain it in an easy way. There is no need to go into so much depth. You are just understanding this from a

knowledge point of view. Now I am taking you back to the normal way. Okay ? This is for first-year students. I

basically told you the reason for which students this is for. This is also for first-year students. It is for those

who want to clear concepts in higher semesters. For those who want to study for backlogs. It is also for those who

are preparing for competitive exams and those who want to study at a core concrete level. Okay? PK Science has

written that my backlog paper is in February. There is plenty of time. You will clear it before that. You will

complete it before that. Your subject will be cleared. Only the exam will be left to take. Okay? So now let me tell

you again how to understand linearity in simple words. We understood linearity in a detailed form just now.

Okay? A simple way to understand linearity in an easy way is any element that follows Ohm's Law. Keep just one

thing in mind. Ohm's Law. Why am I mentioning Ohm's Law? Because, see, linearity comes into play then. Between

what does linearity occur? Between V and I. It is a linear relationship between V and I. Meaning, suppose I

increase V here. If I keep increasing the supply potential across an element, then the current also changes in the

same proportion with respect to it. Okay? The current also keeps changing in the same proportion with respect to

it. For example, look at the case of a resistor. You keep increasing the voltage. Read the entire Ohm's Law

regarding current. You will find this exact definition in it. Okay? So the current flowing through the element is

directly proportional to the voltage applied across its two ends when all the physical conditions are kept

constant. That's what we say, right? So , the current flowing through that element, the current passing between

two points, is directly proportional to the potential applied between those two points. Because of this, the concept of

linearity emerges. Okay? So, for all the students who have exams in January, as you have written, you can study

completely stress-free. We have enough time to comfortably complete the entire syllabus of Basic Electricals and I

will also get you to practice relevant questions. Okay? From the university point of view, for those students who

have university exams. So, you can be completely relaxed. Those whose paper is in January are on the safe side, so

there is no need to worry. Okay? So, what would be the examples for this? I Am Gaming asked, "Sir, what would be

the examples for this?" I already gave the first example right here. Ohm's Law element, we state Ohm's Law as V

proportional to I. And V = I*R, so the first example you have is a resistor. Okay? Resistor. So, when you provide

any potential across these elements, as you keep changing the potential, the current will also keep changing in the

same proportion. Okay? So, what will be the examples for this? Let me write down the first example for you. So,

every element that follows Ohm's Law. All are linear. All of them are linear. Resistor, Inductor, Capacitor, As you

study further about impedance, reactance, and impedance, everything falls into this category. Everything

falls into this category. Right? Prabhakar wrote that the Mahagenco exam is also in January. For the MAHAGENCO

exam, you actually have to prepare for many other subjects as well. Dear, you will also need to prepare things in

short first. If you have a little time and want to manage this along with studying other things throughout the

day, you can study from the root level, because I will teach everything from the basic level here. Starting from the

basic level, we will gradually reach the advanced level. Okay? So, if you can spare about an hour daily, you can

definitely attend this. But let me tell you, it is a time-taking process. By about December, all your topics will be

completed thoroughly. But in such a great way that once you study it, everything will be complete. It will be

like that. Okay? So, this is one point. But if you are preparing for the MAHAGENCO exam, you have to study

things in short as well, and keep other subjects along with this, not just one subject alone. Okay? This is my

suggestion. Absolutely, Charu, definitely. So, we will gradually increase the time and other things

later on. It's just the beginning, and because you all have a lot of pressure from college as well. You have to cover

a lot of content for college. That is why I am not putting too much pressure right now, and as we gradually speed up

the subject, it will be fun. So, I told you two things about linearity. You have two ways to define linearity. One

is that you can state that all elements which follow Ohm's Law, resulting in constant VI characteristics, are all

linear elements. The second way to explain it is that linearity means a combination of any element that follows

both the principle of homogeneity and the principle of additivity. So, the principle of linearity is formed by

their combination. Okay? For example, if I am giving excitation and getting a response, how will homogeneity be seen

to be followed? If I provide excitation E1 (t), the response is I1 (t). Okay? If I multiply this excitation by

something, say alpha, then what could be the response to alpha E1 (t)? Two types of responses are expected. Either

it will be alpha I1 (t) or it will not be equal to alpha I1 (t). If it is not equal to alpha I1 (t), then it will be

called non-homogeneous. Okay? And if it is equal to alpha I1 (t), meaning the response changes by the same factor,

then it is definitely following homogeneity. On the other hand, regarding additivity, if I sum these

two excitations, I should also get the sum of the responses in the output. Right? So, it means if the responses

are changing in the same proportion, then the additive property holds. If the responses are not changing in that

same proportion, then it is not following the additive property. And if it is not additive, then again, there

will be an issue with linearity. Then it will go into the non-linear category . This is important. Right? This is

important. Oh, your college classes haven't started yet, right? Then that is very good. Okay? Then that is

perfect. Then you can easily complete everything with concepts. So this was one way. So these, and let me quickly

tell you the examples of non-linear elements. Time is slowly running out. Let me quickly tell you the fourth

point. Fourth is the non-linear element . Non-linear elements. Okay? So, all those elements that do not follow Ohm's

Law. Now it's easy. Now you can easily tell. Whatever I explained above, the opposite of that will fall into the

non-linear category. Meaning' Those elements which do not follow Ohm's Law are considered to be non-linear

elements ', are considered to be non-linear elements, those that don't follow Ohm's Law, whose V-I

characteristic cannot be constant. Meaning, what will their characteristics look like? You know,

their characteristics will look something like this. Look, if you go to plot their graph, if you go to trace

their V-I, suppose V is written here, I is written here, if you go to trace it. You will see some relation like this.

You see, from this point O to this point A, there is no linearity visible here. And after A, you will see a

slight change in voltage will lead to a drastic change in current. A slight change in voltage. A high change in

current. Such a difference is being observed. And from O to A, I am increasing the voltage. The current is

almost constant. Nothing is changing within it. Non-linear characteristic, not following Ohm's Law. Can you say

here that V proportional to I is being followed? It is not being followed. These elements do not follow it. Which

elements are these? Any idea? Your exam is also in January. Okay. Right. Right. PK Science has written that, well, they

are just going on. They are continuing because of the lack of attention. Okay? And there is a night class, maybe it

can be managed at this time. Right? You have to study everything. You have to study everything. If you are preparing

for competitive exams, you have to carry everything along. Tech, non-tech, everything is necessary. Everyone has a

marks weightage, brother. Everyone has a high marks weightage. It is quite significant. Alright, okay. So, is it

clear up to here which ones are the non-linear elements? Let me quickly tell you its examples. Non-linear

elements, like if you go into the category of semiconductors. The example you are seeing here in the graph, you

can call them diodes. Take any diode, PN junction, Zener, or any type. Okay? Photodiode, light emitting diodes,

everything, take transistors. Right? Etc., these all come under its examples . These all fall into this category.

These are all non-linear elements. Okay ? These are all non-linear elements. No Charu, we will gradually increase the

time. So it won't go until Feb. It will be done way before that. It is just the beginning. Right now we are studying

for 1 hour. We will gradually alter the time. We will increase it. And we will complete it quickly at speed. Okay? PK

Science has asked about the daily timing. Uh, 8:30 to 9:30 PM is the daily timing. Photovoltaic diode, yes

Prabhakar. Okay? So this is the example of non-linear elements. So, up to where I have brought you, I will pause here

for a while and take you to some questions. Okay? I will cover the remaining points for you as well. But

after this, I will quickly take you to the questions. See, this is a sample of a question paper. You see, I am telling

you this so that you get an idea. Right , about where the things you are studying will be useful. So this is a

cutting of the AKTU End Sem Examination paper 2020. Everyone, look carefully. B.Tech Sem 1 Theory Examination 2020-21

' Basics of Electrical Engineering ', Time: 3 Hours, Attempt all the sections . If any data is missing, then choose

suitably. And the total marks, here this was a 100-mark paper, okay? Section A, in this it is given to

attempt all the questions in brief. The question reads, look carefully at questions A and B, it says: Define

ideal voltage and current source, and B says: Define active and passive elements. Based on what you have

studied so far, see if you can answer this question. The second one is a two-mark question. There were 10 such

questions of 2 marks each. Among them, the topic you are currently studying, you will see its B-point right here. No

Indra, right now all the classes are on YouTube, so you can join on YouTube. Completely tension-free. Okay? So, you

will be able to do this. Look, this is a university question. You were asking about AKTU. That is why I told you,

look, this is the paper. It is a paper clipping. After studying the next class , you will be capable of answering this

first question as well. In the next class, we are going to study exactly this. I will tell you about ideal

voltage, current sources, independent sources, and dependent sources. You will start being able to solve all

these questions. That is how the confidence will come. Right? You will be able to do this. Okay? Sir, from

which year should I start GATE preparation? Because it is my dream. You can start from the third semester.

If you are in the third semester, then you should begin it. It is a good time to start. Okay? Okay? You will be able

to solve this question. Define active and passive. Well, what if we talk about other universities? It is not

like it is only asked in one. Let's see in some other university. Okay, so this is the AKTU 18-19 paper. AKTU 18-19

paper. Look, this is the 18-19 paper. See, it is written here: define with examples. Okay? This is the same paper.

See, the paper ID is given here. The subject code is given here. You can match it with this too. This is a 100-

mark paper. It is just the beginning, you are studying the content for the first day, and from the first day

itself, you will be able to solve the first two-mark question. See, define with examples active and passive

elements. Okay? The first one is done, active and passive elements. And the upcoming topic is bilateral and

unilateral elements. Look, this question has appeared. It is a two-mark question. After studying this, you will

be able to solve this entire portion as well. Then after that, we will study ideal current and voltage sources. You

will be able to do that as well; this entire content is from the second-year AKTU question paper. Right? This will

be doable. Alright, let's see, is there a paper from any other university? Look , this is the CSVTU Bhilai paper. CSVTU

Bhilai 2020, these are all recent papers. Isn't it? First or second semester examination, November-December

, AIC scheme. It is applicable to all these branches. Basic Electrical and Electronics Engineering. Time allowed

is 3 hours, marks are 100, and minimum passing marks are 35. Right? Attempt all questions. Part A is compulsory

here. In this university, Part A is absolutely a compulsory part. Right? And you have to attempt the remaining

ones. As we proceed further, I will show you how the other parts will look as well. See theirs too, in Unit 1,

they have asked to differentiate between active and passive networks, and linear and non-linear circuits. It

looks like you guys will easily score all four marks here. Both questions are for two marks each; these are all from

the university. Thank you so much Inder , thank you so much my dear. Right, Guruji wrote asking if the class will

end? I just want to show you these questions, because you are studying for the first day, man. You should know

whether questions from the university actually come or not. I am showing you just for this reason. Then we will end

the class after this. Right? Then we will study further in the next session. Right? So, this will be doable. You are

in the third semester, right? Oh man, then you can definitely start your preparation. Right? So it has been

asked in this as well. Active-passive has also been asked. Linear-non-linear. You just studied three or four topics.

The questions are coming directly from there. Right? Two-mark questions. So you will get an idea that universities

ask these as short notes, and maybe there is an AKU paper from some university too. Come on, you were

asking about AKU Patna, look, I have the AKU paper too. Look at the very first question and see what is written.

Right? This is a 70-mark full paper. It is a 2019 paper. The code given is 1001001. A 3-hour paper. Right? Marks

are given. Question number one is compulsory. You see, this short note section appears in a compulsory form in

almost every university. In almost every university. All right. Okay. I Am Gaming has written that sir, it was

great, the questions that weren't moving until yesterday. Are getting solved today. Thank you so much my dear

. This is the confidence I want to see in you all. If this confidence comes into you today, then it will be great.

That is all I need. This is exactly what I am telling you. Just start studying. Look at this university paper

. You are solving another university's paper. What is the problem? You are able to solve the first question.

Define active and passive elements. How much have we studied yet? We have only studied a little bit so far. You are

solving two-mark questions from day one . Now, I will keep getting you questions from other universities and

show them to you right here on the board. You judge for yourself whether you are able to solve the questions and

if your confidence is growing or not. We will keep studying the content in the best way. Okay? Keep attending

regularly and gradually with every session, you will feel that we are increasing the speed, and studying in

the best way will be fun. I am ending today's session here. You have more sessions lined up. So attend them

quickly. Study in the best possible way . Wherever you have doubts, keep asking me, stay connected. Okay? See you all

in the next session. Till then stay connected and I hope that whatever we studied today, you have understood it.

We will meet in the next session. I will continue teaching you the content from here onwards. Okay? Till then take

care. Keep studying well. Thank you.