Mod-01 Lec-08 Summary of classical electromagnetism

Lecture Series on Classical Physics by Prof.V.Balakrishnan, Department of Physics, IIT Madras. For more details on NPTEL visit nptel.iitm.ac.in

[@shravankumarhh4016]

Indian Richard Feynman ..... Has a unique style of Teaching is Marvelous.. Stay Blessed Sir ,,,...

[@sreajan]

YOU ARE PROBABLY BEST PHYSICS TEACHER IN THE WORLD SIR.

[@kiransonnad9250]

I hope the die-hard Balki fans won't mind a negative comment. I was a student at IIT-M for just a semester in 1992, when he taught mathematical physics. He gave the same lecture then, about 15 years before this one, and the content is quite the same. Some years later I went on to do a Ph.D. in physics in the USA and part of my work was in computational electromagnetics, a field I continue to work in. Over the years, I clearly remembered what he had said to us about the 8 equations and 6 unknowns situation, which I now know is not quite right, and I see the same inaccurate statement being repeated in this lecture, about 15 years later! The correct explanation is as follows: The vector equations, which have time derivatives are initial value problems, and the scalar equations put a constraint on the initial conditions for the vector equations. Once a set of initial conditions that satisfy the scalar equations are given, it is sufficient to evolve the system using just the vector equations alone, which amounts to solving six equations with six unknowns. Thus, neither are the scalar equations "redundant", nor is anything "jumbled" up!

[@manabranjanghosh]

makes sense

[@anaathgalikakutha111]

I agree with Kiran. Sometimes one gets a feel of what a set of equations mean only when you apply them to solve real life problems. Otherwise your knowledge gets restricted to what was "written in the textbook' or the notes that you took when you "heard those lecturers".

[@PrashantDelta]

I watched this lecture one and a half year ago and it was a bouncer..later with practice I was able to appreciate it. Brilliant physicist.

[@seyedfowad]

This was probably the deepest most interesting lecture in this subject I've ever heard, and believe me I've been in so many physics lectures so far! Thank you very much professor Balakrishnan for reminding us how much physics is beautiful! and thanks to this great youtube channel for sharing knowledge with the world! hats off to you...

[@shekharsharma506]

these lectures of prof.balakrishnan are really gems.these lectures should be published as balakrishnan lecture on theoretical physics.i think each theoretical physicist should watch these lectures.this is the way how physics should be taught.

[@drscott1]

Omg this professor is amazing!! What a level of understanding and information sharing

[@ozzyfromspace]

Professor Balakrishnan has a truly beautiful mind. There was a period of time when I felt stupid and demoralized about myself and he, and Professor Gilbert Strang (M.I.T.), woke me up. The deep math and lucid visualizations do it for me 🙏🏽❤️🎊😊

[@soumikchakraborty9885]

Why divergence of A is 0 ?

[@soumikchakraborty9885]

Please reply

[@kaustavchakraborty1406]

Studying electrodynamics is incomplete without enjoying this lecture. Best of all!!

[@dharmaraj93]

It feels like the nature came down and started teaching physics .

[@arrabalimaz622]

indeed

[@Conqurer26]

🤩

[@sahiljs5198]

Two legends of indian physics teaching: HC VERMA and PROF. BALAKRISHANAN

[@pmohanram]

I had the pleasure of having Prof Balakrishnan as my teacher when I attached IIT Madras in the mid 1980s. I had him for 3 semesters and was truly blessed. All these years later, as a professor myself, I try to emulate him and his inimitable teaching style, and probably fall woefully short. Thankfully, I teach much simpler stuff at a business school.

[@ravishanker785]

pmohanram by the way at what level these things are taught. I mean ( B tech ,MSc or M tech ) ?? Because I am graduate now in physics and still don't know these things in this much generality . I Only heard the name tensor and the professor was proving things using index notation which I am not familiar of . If these things are taught in B tech then in which branch and in which semester.

[@jothibalamurugan6445]

@@ravishanker785 M.sc level

[@gabbarisback6052]

@@ravishanker785 this is only jee advance level😂😂😂

[@VinBhaskara_]

He is my inspiration to continue in Physics. GODly

[@GuillermoValleCosmos]

This teacher is absolutely awesome.

[@wagsman9999]

Brilliant. I have learned more on youTube than my four years at a sound engineering university - seriously. Some of the best technical content is coming from India. Thank you.

[@PhysicsThroughComputation]

kzbin.info/door/ouvWX-31Xkh8MQ_hCoYqAQ?view_as=subscriber

[@AritraSinhaphysics]

I learnt more from this single lecture about physics than in my five years of masters study

[@santanusingh7921]

Unification of all concepts in one lecture, that's the beauty of Prof. Balakrishnan

[@Mikey-mike]

Prof. Balakrishnan is a fine teacher, second to none. Well done, sir.

[@akshaybaviskar1582]

Sir , ur lectures are drugs for me!! U r exceptionally brilliant

[@arrabalimaz622]

pardon me from now I will also use it I found his presonality as a teacher is really conceivable n convincing thus we do follow him if he have more videos than it will be great sir . .

[@MrAkashvj96]

This is a very good lecture but it's also far beyond what I was expecting it to be.

[@supern0is349]

this guy doesnt check a single note to write down these equations i cant barely remember all the derivations and formulas for simple harmonic oscilator, and i've seen this countless times. He also teaches all of sorts of subjects in physics- from mathematical physics, to non equilibrium statistical mechanics, eletrodynamics He's trully a master of physics. Amazing to watch

[@qlw15138]

Outstanding lecture. This is teaching at the highest caliber.

[@g.srinivasanvalli9241]

True

[@experiencephysicsbeyondima781]

17:59 - 29:28 beautiful explanation and a sweet description of Helmholtz theorem

[@paulg444]

"its not hard to derive".. priceless!

[@dipjyotisarma5868]

Which I could seat in the real classroom of his lecture....Excellent lecture...

[@sam08090]

One of the best lectures in KZbin ❤️

[@admiralsnyder4791]

What a great show!

[@salmanzabha7428]

deep lecture for physics student...love it

[@jitendraphyma1372]

It's very useful lecture for me ....lecture give by balakrishnan sir, i use it as a reference also.

[@animalationstories]

Pure Gold .. you are amazing sir

[@debsub1]

For the constant electric field , isotropy is broken, hence Lorentz invariance of Maxwell's equation, therefore it is not OK in having constant fields in electrodynamics.

[@JaydeepSinghTindori]

I am inside the charge now and He is playing with me. Awsm Awsm.

[@dr.rahulgupta7573]

Adbhut ! Ati adbhut !!

[@javlonrayimbaev4454]

he is the best lecturer

[@mjramanuj7676]

THE BEST

[@JasveerSingh-px2xr]

awesome lwctures

[@sarthaktiwari3357]

He should be teaching mathematics too......... He knows so much of it.... And he can think beyond average thinking..... Thank you so much professor............. I'll try my best to imitate you

[@uday4617]

he has a whole book written on mathematial physcs

[@ArshadKhan-wd7vw]

I salute to you.sir

[@iali361]

Outstanding lecture! The second gauge is Lorenz gauge, not Lorentz gauge.

[@brotherstech3901]

Thank you sir . 🙏

[@hemantj675]

For free space rho and J are zero so how can these be for free space? At around 3.00

[@skadogg22]

Very informative lecture. Well explained and easy to understand.

[@pritamjyotiborah2391]

LHS of the 4th maxwell equation should be ... curl(B) = ...

[@lucaperuzzo2243]

Hello, great pleasure listening this lesson! and good understanding on "very very deep reason" =) yet, I couldn't get completely the part about longitudinal and normal components, why curl is associated to the normal/transversal component and vice versa? May some one give me a good reference or add something?

[@afreenhameed9414]

this might help en.wikipedia.org/wiki/Helmholtz_decomposition

[@rgudduu]

Dot product of vector1 with vector2 can be seen as a (scaled) component of vec2 in direction of vec1. Cross product of vec1 with vec2 is another vector which is perpendicular to vec1. Longitudinal = along = in sane direction. Transverse = perpendicular direction. Prof above shows at 25:00 that- Exp(i.r.k) can be seen as a vector field as a function of location r vector and direction k vector. Del dot operator gives a dot product with k Vector, so it a component along k vector. Del cross operator gives a cross product with k vector, so it is perpendicular to k vector. So at location r, taking any random direction k, the del dot gives the longitudinal component, and the del cross gives the transverse component.

[@appannagari2019]

The professor .

[@arrabalimaz622]

D^2 ¥ = 0 laplacian equation in first dimension.

[@mayanksharma5516]

Some stupid student at 57:23 doesn't know how to courteously ask question... Balakrishnan sir is awesome..#G.O.A.T.

[@abhinavjeetojha3368]

Maxwell Equations❤

[@arrabalimaz622]

curl of gradient is zero after this I'm gonna learn about the gradient divergence n curl relations videos n possible relations okay let's see

[@daniyal6894]

This is for which class?

[@MrNerdpwn]

Basic electromagnetism like this is taught in Bachelor's level physics in India. If you go for masters, you'll get to study relativistic electrodynamics and covariant formulation of electrodynamics (tensorial form of Maxwell's equations).

[@AkashKumar-fv7uo]

anyone in 2020????

[@arrabalimaz622]

hey brothers there I belive negative answers as nobody seems interested n nobody will reply is one of the possible outcome sir great n there is outcome in your favour too so we need to take chance if possible.

[@arrabalimaz622]

possions n wave equation solution okay is sound light is 1D,2D or 3d equations n does the same wave equation is sufficient I believe see

[@tijerinaivan]

Jesus, will i die without understanding what the hell his saying?.. not as in language but as in concept.. Anyone know some material/videos/pages i can read to get to this level of understanding?

[@afreenhameed9414]

honestly I didn't understand this either at first. To really get a taste read Mathematical methods for Physicists by Boas and review basic E&M

[@arrabalimaz622]

can a matric be 1 row n 1 coloum sir?

[@BheemChandGoyal]

⚠: Don't double tap on right screen, you will have to double tap on left.

[@irodov_field1663]

What are those 6 unknown

[@georgeobrien1011]

The three components of vector E, and three components of vector B

[@pvaddi2001]

Classical example of our education of equations without understanding of basics and without their application

[@arrabalimaz622]

laplacian system in reference of divergence of A n than gradient. ..

[@arrabalimaz622]

normal n divergence relation n independent of the direction. ...

[@arrabalimaz622]

only if the curvature is tending to zero concept ?

[@arrabalimaz622]

value at the point is the geometric mean of either point

[@arrabalimaz622]

45 possions n wave equation just make it zero because it seems complex so we can do now apply it on the electrodynamics as well as electrostatic n wave equation 😀

[@arunbhaskar4013]

The second gauge condition discussed at 1:06:00, I think, should be spelled "Lorenz gauge" rather than "Lorentz gauge". Lorenz gauge condition is named after Ludvig Lorenz and the Lorentz transformation is named after Hendrik Lorentz.

[@arrabalimaz622]

2.gauge transformation need to be solved what's next?

[@arrabalimaz622]

charges at the positive equilibrium n absolute maximum

[@arrabalimaz622]

gauge invariance what is this sir invariance why he is less certain.

[@arrabalimaz622]

divergence of A = scalar quantity good than we do....

[@arrabalimaz622]

harmonic property of the laplacian n del operator

[@arrabalimaz622]

gradient of the divergence of A = laplacian na ? it's divergence of gradient I know

[@rgudduu]

high quality and depth. May be difficult to grasp for new learners though. Also, his habit of wiping out the board without giving sufficient time to absorb it doesnot help

[@tijerinaivan]

would you hapen to know some video for new learners? im not that dumb but not that smart...more dumb than smart i´d say..

[@rgudduu]

Ivan Tijerina u may see Prof DK Ghosh video lecture on "Electromagnetic Theory" (module-1 lec1,2,3) for a good explanation of vector calculus (grad, divergence, curl, surface integral, Stokes theorem) or Prof RK Shivgaonkar video lecture on "Transmission lines and EM waves" (lecture 16-34 around) for a great ug level course on em fields. In addition, the Prof in this lecture uses Linear Algebra concepts... hope u r familiar with those

[@tijerinaivan]

Million thanks, i will do.. I am familiar with those concepts, defenetly not an expert, but i am, i am a petroleum engineer (barely but still).. Nice to know the clasification of this algebra i will review the concepts aswell.. I was never the best student but am eager to learn now.. thanks again!

[@arrabalimaz622]

circulation per unit area curl interesting.

[@arrabalimaz622]

all electric field not as a gradient of scalar

[@arrabalimaz622]

electrostatic using vector potential not the ....

[@arrabalimaz622]

what happen charged partice is moving or so .. ?

[@arrabalimaz622]

26 conversation of diffential to algebraic system fourier games. ...

[@arrabalimaz622]

kai the gauge equation

[@arrabalimaz622]

pardon me

[@arrabalimaz622]

electrostatic non time dependent equation than possions equation.

[@arrabalimaz622]

anyone thinking there students are from south mostly?

[@arrabalimaz622]

what uniqueness of vec B

[@arrabalimaz622]

what is the language students are choosing to speak hindi or malayali 😆

[@sreeharie821]

Haha you don't even know that malayali is not a language .

[@chrisa4284]

note to everyone who ever watches this: start watching at 1:00 as this video has the most annoying intro ever

[@PurushottamGuptaOM]

+chris a try googling the vedic chant , Om Saha Nau-Avatu | Saha Nau Bhunaktu | Saha Viiryam Karavaavahai | Tejasvi Nau-Adhiitam-Astu Maa Vidvissaavahai | Om Shaantih Shaantih Shaantih || Meaning: 1: Om, May God Protect us Both (the Teacher and the Student), 2: May God Nourish us Both, 3: May we Work Together with Energy and Vigour, 4: May our Study be Enlightening and not give rise to Hostility, 5: Om, Peace, Peace, Peace.

[@SKCSK792]

You are so ignorant !

[@dharmendrasharma9541]

You lack patience....

[@zachzanal1067]

I agree to you,Badly timed verse!{It is very irritating,though it is a meaningful verse,like Gold is precious,But it can't quench your thirst}