I am not sad even if Prof HC Verma's soln is proved wrong. I am talking to the viewers, that don't conclude yourself with sadness, or don't compare both. Even Prof Walter Lewin was wrong once during a conflict with 'Electroboom'. So be happy and create a space in mind that Nature is really beautiful, works so beautifully that we can endlessly explore and explain it. Thank you :)
This is the beauty of science, you don’t need a smart board, a high-fi studio to teach science. It only requires purity in knowledge and intellect and a simple black board is enough Thank you sir for your great efforts!!!
@@maxwellsequation4887 that was deadly one, because Prof Lewin compared Electroboom on basis of Degree/Qualification. We have to just admit that physics is never ending, nature can be explored endlessly.
I didn't know that this video was somehow related to walter lewin sir's recent video.. But seriously, my reaction after getting this was unpredictable.. The first thing came in my mind that the answer is given by Indian Physicist and second, that too with the precious smile of HC Verma sir.. ❤️❤️
Sir, after watching Prof. Lewin's view on the question, its my humble suggestion to kindly make another video with a deeper explanation. As a physics lover, i love healthy discussions and what is right should come out for us. Regards.
@@hcverma2928 sir I have a question. we know that electric field created by static charges is conservative and hence the work done to take a charge around a closed path is zero. But when we define emf of a cell we say that it is the work done by the cell to take a unit test charge around a circuit. sir my questiob is that are not the two statements contradictory??
@@amibuntyda that isn't closed path... It would have been closed path if initial and final position would have been same, but, there is a potential difference (cell) between the initial and final positions.... So it isn't a closed path...
When some big shots tried to deny the answers and logic of some not so popular scientists/professors these not so popular came out to be known as maxwell, laplace, Einstein. Anything is possible!! Just focus on your work. Thank you sir for such a wonderful explanation.
@@nishaupadhyay2577 Buoyant force acceleration? The acceleration any object feels at earth surface is due to the NET force acting on the object (a = Fnet/M). The two main forces acting on an object in still air(atmosphere) is the gravitational force or object's weight due to the object's mass less the buoyant force acting opposite to the gravitational force on the object (Fnet = W - Fb). The buoyant force is equal to the weight of the air displaced by the object's volume. Since acceleration is F/M, then this buoyant acceleration you are asking about would be ab = Fb/M from a = Fnet/M = (W - Fb)/M = W/M - Fb/M = g - ab where g = 9.8m/s^2 However, we usually talk about buoyant FORCES but not buoyant acceleration GH Sept 13, 2021
"Green board, white chalk & smiling face" are the only assets that professor have! Sir,you're the epitome of simplicity, a truly gem of INDIA. Thanks for your incomparable "SMILE", sir.
Sir!Despite being such a great professor of Science, the smile and calmness on your face white teaching shows how much you know about life and psychology ✌👏👏
Sir you explain very nicely.. I also came to the conclusion that current will be induced without emf..as I knew that in mri machines emf Is not applied but there is high current in the electromagnet inside.. But now I got more clarity
Heartful Respect to a legendary teacher Verma sir🙏🙏🙏... my opinion is that the only thing that matters is" the approach" to anything! the results can be anything unexpected or expected. Humans can never reach to perfection.and sir is too a human being but different from ordinary people.just 1 doubt cannot shook the whole of legendary contribution towards physics by Verma sir! you are a legend sir ❤️ n you will always be! sir you resides in all physics lovers heart ❤️. Great Respect to both Verma sir and Walter Lewin sir🙏🙏🙏
Legends are contradictory with this question and it came in jee advance after 3 week of this video. Thanks to HC verma sir and Walter Lewin sir. I got 4 marks from this lecture.
If it was normal Lenz's Law or the 'like' pole - the same pole - produced by the superconductor against the encroaching (moving) bar magnet, the magnet would not float, would not levitate, atop the superconductor - the magnet approaching the superconductor would be cast off to the side, just as in a normal Lenz's Law demonstration. There is something different occurring with the superconductor - because the encroaching magnet, if placed atop a superconductor, is (1) repelled by the superconductor but also (2) remains in place, levitating, above the superconductor, and is not tossed off to the side. This is not Lenz's Law. The entire problem with common physics today is complete failure to assess and investigate the constituents of the Vacuum (not the air-pressure-free vacuum, the QED Vacuum). Until the exact physical nature of the Vacuum is examined - rigorously - these types of questions will fail to be answered accurately. "So you think space is not empty? You think there are 'constituents' in empty space?" Yes. Here's how to demonstrate it. 1) put one neodymium (strong, rare-earth) magnet in each hand with the "N" poles of the magnets facing each other 2) try to push the two "N" poles together so they physically touch (you will not be able to if the magnets have any noteworthy size) 3) now, while you use your hand strength and coordination to try forcing the "N" poles together, there is still a gap of space between the magnets because you cannot easily force the two "N" poles to touch together 4) CAREFULLY LOOK into the gap between the two magnets - IT LOOKS EMPTY It is NOT empty. The constituents of the particle-antiparticle Vacuum are not discernible to our vision, but the magnet test above lets you feel the effects of the constituents of space. An invisible, quite strong force preventing you from forcing two pieces of metal together. If you're curious along these lines, note this. The 'virtual particles' of the QED Vacuum - such as electron-positron pairs - are claimed to 'pop into existence, then self-annihilate' It is long established in the lab that the annihilation of an electron-positron pair produces gamma rays. If the 'virtual' particles actually self-annihilate, the Vacuum would sustain an easily detectable gamma ray background. And IT DOES NOT. The spin of the electron and positron are equal, and OPPOSITE. The particle-antiparticle pairs that fill the Vacuum are persistent, and dipoles can be induced in them. They do not self-annihilate. They are not detected because they are dipoles and cancel. The electron-positron dipole consists of: - a negative electron and a positively-charged positron - opposite spin on the two ends of the dipole The constituents of the Vacuum can be manipulated (dipole stretch induced, or dipole stretch removed) but the only way to do so is with coherence conditions imposed on the atoms of a matter object. Coherence imposed on piezo materials by a maser is one way to alter the Vacuum coherently. The Vacuum very rapidly quenches any attempt to alter its conditions unless the attempt is coherent. Artificial gravity can be produced in this manner. .
Sir your books helps lots of student and awakened love towards physics But in changing world I request you to creat a new master piece on platform of TH-cam.
In Science you are never wrong! This simply means that this is the way by which you can't get right solution. This explores our mind to make new possibilities and challanges to look into that problem in more effective way. Inspired by Thomas Alva Edison. Respect for both of the teachers. We are learning a lot from you all. 🙏❤️
Sir if earth moves at 1675km/hr and if we moved a car at 50kmhr at the same direction so technically its speed will 1725kkm/hr ???? Please answer the question
@@dhruvmishra2000 it depends from which frame you are asking if you are asking from a stationary frame outside the earth then it will be 1725 but if the frame is inside the car then speed of car will be zero if the frame is outside the car and on the earth then it will be 50km/hr.
@@dhruvmishra2000 no bro car is moving on surface . Of earth so technically tangential vel of earth gets vectorilly added to it but in the frame of outside earth
Thank you sir , when in a video i saw this question, i guessed a bit about lenz law but from this video i got conceptual clarity. Thank you sir. Please keep making more such videos.
Physics is a royal subject which wise people can only understand the truth behind it. One among the people is Prof. WALTER .L, who is so wise enough to point out mistakes of others.
I happen to came across a quote by Richard Feynman that "science is the belief in the ignorance of experts". Which is to say that there is no scientific authority, humans can all be wrong at one thing or another and that's ok, because remember the moment of being wrong is the moment of humbleness and more importantly learning.
Literally respescted sir, even in generation of online mode due to corona virus it really helps to fall in love with physics is only possible by your these intresting sessions of physics....inspiring for us🙏🙏
And now.... Sir Walter lewin denied this solution as i have seen 23 minutes ago his solution. But i hope as a professionals of physics, you both will get a clear thought process about its solution.
A DISPLAY OF A VERY POOR CONDESCENDING ATTITUTE BY WALTER LEWIN! It all starts with his statement "I doubt even Prof Verma can answer this problem". Then goes on to call the solution "blatantly wrong" " and "it is wrong physics" in a poor taste. Dear HC Verma Sir, thanks for all ur contribution to the student community. Lewin just cherry picks on one phrase of HC Verma of the current being in the material and then calls the complete solution "blatantly wrong" and says that "it is wrong physics" where in fact most of the solution is absolutely correct. It's just that HC Verma should have used the language "E and B go to zero deep inside the superconductor and he could have described the distribution of current inside it but it goes far beyond the scope of JEE (the question said it was for JEE). The bigger irony is that Walter Lewin who calls Verma's solution wrong himself does not understand superconductivity and he so instead of using the phrase " deep down", says that E is zero everywhere inside . LEWIN himself makes TONS of mistakes in his question video... Zeroeth of all, he calls it a JEE problem...Seriously? Superconductivity? Now comes the first point. Lewin says that there can be no electric field inside the superconductor. "Blatantly Wrong!!!". Ever heard of london penetration depth? Lewin says in the solution video that the current will flow on the surface of the superconductor. He says that there can be no current inside the material. "Blatantly Wrong!!!" Surface by definition has zero thickness which will blow up the areal current density. The truth is that the current does flow inside the material but near the boundary of the material(near the surface, not on the surface!), significant amount of which is upto the penetration depth. Only deep down the superconducting material, B and E go towards zero. This penetration depth can be of the orders of nm to um or even could become very very large if you happen to go near the critical temperature. Second point, Lewin says "the beauty is...faradays law...creates an emf...an electric field..just OUTSIDE the superconductor"....LOL... " Blatantly Wrong!!!" What do you mean by "just outside"? Faraday's law holds for any hypothetical geometrical loop created anywhere in space. This is what HC Verma explains in his solution video and this is what Lewin needs to learn from him. And it is definitely clear now that you have not heard of 'penetration depth'. Current cannot propagate "outside" the material. The thing which Lewin and many others wrongly call a surface, is not a surface but a volume. In Lewin's words, HC verma's statement that current is there inside the material is wrong. Lewin also states "there cannot be any current in the superconductor".This is wrong! The current is definitely inside the material (LOL Lewin, where else the current could be?!). I again reiterate that current is not propagating on a surface but in a volume. Coming to the second point, Lewin gives insufficient information regarding the external magnetic field. What if its magnitude is greater than the critical magnetic field? The superconducting state will be lost. Third, Lewin gives insufficient information regarding the thickness of the superconducting wire. What if I use a thickness comparable to the london penetration depth of the superconducting material?
Prof HC Verma is correct in saying that electrical field inside the super conductor is zero. However, at the surface/boundary of superconductor the electrical field won’t be zero. This is the one thing Prof Walter Lewin *added*. In this case, current will flow on the surface of superconductor only. On side note: I have never found a better book than concept of physics. It was this book that made me crack IIT JEE. Thanks.
@@AsifShah-fi7oj By definition- it seems like. However, the way I think is that at the boundary of the superconductor- at one side conductivity is infinity and at the other side, it is close to zero. So at the boundary, conductivity can have anything between zero and infinity.
He is sooo humble and kind person I want to meet u sir once in my life And in physics anyone in this world not know completely they just guess with many assumption even Albert Einstein not believe in quantum mechanics but it is true physics is endless and their are soo many many things which are out of our imagination.
@@alexleibovici4834 he has a different perspective of quantum mechanics and when he doesn't believe in quantum mechanics interpretation we say that he was not believed in quantum mechanics he say that their is any mistake by us in very fundamental level of our understanding of universe
@@amansinghkarchuli1005 > when he doesn't believe in quantum mechanics interpretation we say that he was not believed in quantum mechanics If we say that, than we are wrong ! It is because QM works very well, and Einstein knew this. He died in 1955, and by that time QM applications made big advances: in computing spectrums of atoms and molecules, even with relativistic correction, and also quantum electrodynamics (Feynman and others). What he was against is the the Copenhagen interpretation of QM (it is the observer that creates the reality) and he believed that QM, being probabilistic, is not THE ultimate theory. I recommend you Mario Bunge, for example "Philosophy of Physics", Ch. 5.
@@alexleibovici4834 thank you so much brother I am preparing for iit but I interesting in QM so I know a very little things about this, I want to share something which I found in ancient Indian books you know Vedas, Upanishads. In Upanishads the same thing IT is the observer who creates the reality is written and I am so shocked after studying this and in Vedas their is much more than this which today science proof and this is very interesting..
Sir although urs solution to this problem is wrong but u r too a human sir,aap legend ho sir.U are MODERN RP FYNNMAN OF THE WORLD.We all respect U and Walter lewin sir too❤️.
I am so Inspired by you sir...by so many achievements but you are so humble and no compare of your intelligence...I hope I will become like u one day ❤❤
Sir Can the change in magnetic flux can be zero at the very INSTANT during the motion of the magnet? ( since information cannot travel above speed of light )
I feel it must not Because magnetic field lines are infinite and are always present as ideal behaviour of magnetic fields so even on the infinitesimal disturbance on magnetic field would generate emf thus flux≠0 at the very instant
Honestly speaking this was quite easy question, seeing from a iit point of view... like if u have ur concept clear... this is a like a scoring question for u
@mahi jain ya i mean u say that after watching prof Lewin's video... and i never said jee adv is easy... and i am in class 12 prep for iit... i know about jee adv
@@achillesinvader3921 So there was a question (that came in the jee advanced exam), that asked what will happen when there is a changing magnetic field through a coil made of completely super conducting material (u can get the exact question in prof Lewin's channel)... so the controversy was that Prof. HC Verma gave a solution, which was later disagreed by Prof. Lewin... U can check out his video... it is quite interesting
@@achillesinvader3921 First of all this is my school's requirement to have a profile pic in school uniform (which is horrible) So coming to the question, it asked that if u oscillate a bat magnet in and out through a solenoid made of superconducting material, then will there be Electrical field, if no, then isnt it violating Faraday's Law. And secondly is there B field present in the solenoid coil... so u have to explain what is happening... the interesting part is there is a property of superconductor that even in electrodynamic condition, there E field inside the conductor is 0... but then it apparently disagrees with Faraday's law
We Generalise a wire based circuit MOSTLY AS A ONE DIMENSIONAL WIRE with r=0 so it has no interior or exterior or the interior and exterior are virtually not present as if its a line with just 1 dimension. Here we are taking a wire with finite radius where it has a external and internal space different from each other or as if radius of wire is not equal to zero. prof verma did with the idealisation of r=0. I think then it just becomes a thought experiment. But Prof. Lewin did analysed the situation with a non zero radius .i.e the wire has a surface and then internally E=0. I guess with the idealisation Prof Verma's solution is not wrong.
@@jeetendrasinghrawat6661 read the comment carefully. It says "HC verma sir accepted it as incomplete solution". I am asking where did hc verma accept it as incomplete..... And this Walter Lewin, he has a very poor condescending attitude. Calls HC Verma "blatantly" wrong when in fact he was correct for most of the part. He himself makes tons of mistakes in his question video himself and calls others blatantly wrong.
Sir your lectures and problems always create a great curiosity and imagination .you created such an indomitable spirit and interests for physics in us. you reach students through different platforms .you always make sure that quality lectures n education reach to every students to all corners . Heartly thank you sir🙏 we will always be grateful to you and your contributions ❤️❤️❤️
TBH the solution is too convincing and doesn't seems to be wrong. First you learn extra stuff ad do your complete revision of EMI in 13 minutes. loved it..
I think: The current will be close to infinity so that there is a finite emf generated which satisfies j=sigma E. This current will create an incredibly high amount of counter force on the source of the magnetic field that is the magnet.The magnet will be very hard to move causing the emf to drop immediately and current will come down to 0. I tried to think of the situation when the resistivity of the superconducting material tends to zero
Sir I thought it this way: If we try to move the magnet close to the loop, then the loop being made of a superconductor will compensate for the flux produced by the magnet by producing a current in the loop making net flux zero. But when the distance between the loop and the magnet becomes zero then infinite current needs to be produced in the loop which is not possible,so we can say that the loop will not let the magnet move by producing repulsive force.
Prof Lewin says that there will be a current on the surface of the superconducting coil but not inside it. The link to the video in which has posted this solution is th-cam.com/video/fGM5AtwEmuQ/w-d-xo.html But he does not explain why no current inside the coil does not violate Faraday's law. As Prof HC Verma has emphasized, Faraday's law is applicable on any closed loop, even if the loop is intangible. If we want, we can consider a loop inside the coil. According to Faraday's law, an emf will be induced in that loop, which means an emf will be induced inside the coil. Then why is there no current inside the loop?
Sir very useful knowledge, but i have a request, plz try to demonstrate the practical experiment as well, it will bring clarity to understand the concept.
i must say that Kota consist of huge minded prof. who teaches us in such a way that walter lewin sir found this question tougher,we Indians are at a level,that is actually differ in a large mass
Sir can you please elaborate that in case of conductor if opposition is incomplete but still opposition is there then why we are not accounting that incomplete opposite in calculation ?
Towards the end you have said that when magnet goes away the current in loop should be such that it will increase the flux so how magnetic field in loop becomes zero. Since there is current so there should be magnetic field, isn't it?
@@kavan2908 Verma did not mean the net flux continues to increase such that it never goes to zero but the process(Lens Law) tries to keep the flux from the magnet seen by the coil from falling by INCREASING or adding to it with the flux produced by the induced current. When moving the magnet into the coil, the coil sees the B-field and flux from then magnet increasing and a current is induced in the coil in such a direction as to create a flux to oppose and decrease the applied flux to balance it out to try keep the NET flux as seen by the coil from changing. When you pull the magnet out of the coil, the B-field and flux of the magnet are still in the same direction as before but now decreasing in intensity as seen by the coil. The current induced in the coil now REVERSES direction to create a flux to build up and aid the flux from the magnet as it is decreasing to balance to try keep the NET flux from further changing. This is a loosing battle and the net flux will eventually go to zero as the magnet is moved further and further away or flipped to reverse pole polarities. GH
His smile brings an induced smile on my face.
But buddy it's opposite in direction
😅😅😅 ,,, (just a joke;)
I am not sad even if Prof HC Verma's soln is proved wrong. I am talking to the viewers, that don't conclude yourself with sadness, or don't compare both. Even Prof Walter Lewin was wrong once during a conflict with 'Electroboom'. So be happy and create a space in mind that Nature is really beautiful, works so beautifully that we can endlessly explore and explain it. Thank you :)
I'm totally agree with you
Science is all about open argument, even Einstein made several mistakes in his early gr papers
Prof Lewin was correct on Electroboom problem. He was correct and other professors from MIT and other universities agreed with Lewin. read his paper
@@michaelz5633
Tell me where Dr. Verma is wrong?? You can easily see what does he want to tell.
@@ndmaphy he stated that there would be a current in the loop which is not possible in this case of superconductor.
This is the beauty of science, you don’t need a smart board, a high-fi studio to teach science. It only requires purity in knowledge and intellect and a simple black board is enough
Thank you sir for your great efforts!!!
Black board and a clean chalk is like heaven. Smart boards sucks
Mathematicians buy a specific brand of chalk for clean flow
@@krishnabharadwaj4638 did Ramanujan also
Obviously
@@vamsikrishna1304 😅😅😅
Today new digital boards are introduced but this chalk and green board(so called black border give real feel of study).
You are my inspiration sir🙏
So nice. Thanks.
@@hcverma2928 your welcome sir.
I want to be like you sir.
@@priyanshu.tec1 you are jee aspirant ?
@@Neetaimer2024 yes but why
@@priyanshu.tec1 no just for information
This is Not "Lewin vs verma"
This is "Lewin and Verma". A friendly physics discussion. So stop creating a hype for a potential Controversy.
Like the electroboom Lewin controversy
That was big bruh
@@maxwellsequation4887 The real culprits here are we people ourselves who pour petrol on flames.
@@maxwellsequation4887 that was deadly one, because Prof Lewin compared Electroboom on basis of Degree/Qualification. We have to just admit that physics is never ending, nature can be explored endlessly.
exactly
I didn't know that this video was somehow related to walter lewin sir's recent video..
But seriously, my reaction after getting this was unpredictable..
The first thing came in my mind that the answer is given by Indian Physicist and second, that too with the precious smile of HC Verma sir.. ❤️❤️
These kind of healthy interactions make physics more intresting for students like us👍👍
@Tunna I think the channel name is H. C. Verma, you just subscribe there.
*Sir,we love so much your procedure to explain physics in a different way....salute you Sir*
Sir, after watching Prof. Lewin's view on the question, its my humble suggestion to kindly make another video with a deeper explanation. As a physics lover, i love healthy discussions and what is right should come out for us. Regards.
was here two years ago did not understand a word
now after this time i genuinely understand the controversy and what a beauty it is
I am lucky that I am alive to see these two legends Sir Lewin and Sir Verma
NA LEWIN IS NOT LEGEND
Fantastic explanation. I love the energy of this professor :D
Thank you
@@hcverma2928 sir I have a question.
we know that electric field created by static charges is conservative and hence the work done to take a charge around a closed path is zero. But when we define emf of a cell we say that it is the work done by the cell to take a unit test charge around a circuit. sir my questiob is that are not the two statements contradictory??
@@amibuntyda that isn't closed path... It would have been closed path if initial and final position would have been same, but, there is a potential difference (cell) between the initial and final positions.... So it isn't a closed path...
When some big shots tried to deny the answers and logic of some not so popular scientists/professors these not so popular came out to be known as maxwell, laplace, Einstein. Anything is possible!! Just focus on your work. Thank you sir for such a wonderful explanation.
One of the most wonderful men in Physics. 🙏🏻
Best physics professor in the world.love u sir from heart.
Thanks. But no one is best. My style appeals you that is great.
@@hcverma2928 yes sir ,thanku sir
Sir I have a question that ,if gravitational force acceleration is 9.8m/s^2,then sir if we think Is, buyount force acceleration is there or not?
@@nishaupadhyay2577 Buoyant force acceleration?
The acceleration any object feels at earth surface is due to the NET force acting on the object (a = Fnet/M). The two main forces acting on an object in still air(atmosphere) is the gravitational force or object's weight due to the object's mass less the buoyant force acting opposite to the gravitational force on the object (Fnet = W - Fb). The buoyant force is equal to the weight of the air displaced by the object's volume. Since acceleration is F/M, then this buoyant acceleration you are asking about would be
ab = Fb/M from a = Fnet/M = (W - Fb)/M = W/M - Fb/M = g - ab where g = 9.8m/s^2
However, we usually talk about buoyant FORCES but not buoyant acceleration
GH Sept 13, 2021
"Green board, white chalk & smiling face" are the only assets that professor have! Sir,you're the epitome of simplicity, a truly gem of INDIA. Thanks for your incomparable "SMILE", sir.
Sir's Smile = Constant 🥰
and it's differential is 0
Sir!Despite being such a great professor of Science, the smile and calmness on your face white teaching shows how much you know about life and psychology ✌👏👏
Just woke up after spending 3 hours with the concepts of physics book....and ut is amazing to see your video recomendation........
Sir you explain very nicely.. I also came to the conclusion that current will be induced without emf..as I knew that in mri machines emf Is not applied but there is high current in the electromagnet inside.. But now I got more clarity
Very good
Professor Lewin be like now.
एक दम से वक़्त बदल दिया....
जज्बात बदल दिये .. 😄😄😄
#TheHCVERMA💖
exactly... he asked this question
aur baccho ne yaha chipka diya
@@himanshuuni111 lol
@@mayankgoyal35 I think professors don't fight on that whatever be the right Physics they will accept
th-cam.com/video/bZ6pZgAXRL4/w-d-xo.html
And now similar question is asked in JEE advanced 2021........ Sir is really great ....I could understand the question And answer it
i checked the paper there is no such question
It was necessary to respond.
Great sir .
Heartful Respect to a legendary teacher Verma sir🙏🙏🙏...
my opinion is that the only thing that matters is" the approach" to anything!
the results can be anything unexpected or expected.
Humans can never reach to perfection.and sir is too a human being but different from ordinary people.just 1 doubt cannot shook the whole of legendary contribution towards physics by Verma sir!
you are a legend sir ❤️ n you will always be! sir you resides in all physics lovers heart ❤️.
Great Respect to both Verma sir and Walter Lewin sir🙏🙏🙏
Legends are contradictory with this question and it came in jee advance after 3 week of this video.
Thanks to HC verma sir and Walter Lewin sir. I got 4 marks from this lecture.
If it was normal Lenz's Law or the 'like' pole - the same pole - produced by the superconductor against the encroaching (moving) bar magnet, the magnet would not float, would not levitate, atop the superconductor - the magnet approaching the superconductor would be cast off to the side, just as in a normal Lenz's Law demonstration. There is something different occurring with the superconductor - because the encroaching magnet, if placed atop a superconductor, is (1) repelled by the superconductor but also (2) remains in place, levitating, above the superconductor, and is not tossed off to the side. This is not Lenz's Law.
The entire problem with common physics today is complete failure to assess and investigate the constituents of the Vacuum (not the air-pressure-free vacuum, the QED Vacuum). Until the exact physical nature of the Vacuum is examined - rigorously - these types of questions will fail to be answered accurately.
"So you think space is not empty? You think there are 'constituents' in empty space?" Yes. Here's how to demonstrate it.
1) put one neodymium (strong, rare-earth) magnet in each hand with the "N" poles of the magnets facing each other
2) try to push the two "N" poles together so they physically touch (you will not be able to if the magnets have any noteworthy size)
3) now, while you use your hand strength and coordination to try forcing the "N" poles together, there is still a gap of space between the magnets because you cannot easily force the two "N" poles to touch together
4) CAREFULLY LOOK into the gap between the two magnets - IT LOOKS EMPTY
It is NOT empty. The constituents of the particle-antiparticle Vacuum are not discernible to our vision, but the magnet test above lets you feel the effects of the constituents of space. An invisible, quite strong force preventing you from forcing two pieces of metal together.
If you're curious along these lines, note this. The 'virtual particles' of the QED Vacuum - such as electron-positron pairs - are claimed to 'pop into existence, then self-annihilate'
It is long established in the lab that the annihilation of an electron-positron pair produces gamma rays. If the 'virtual' particles actually self-annihilate, the Vacuum would sustain an easily detectable gamma ray background. And IT DOES NOT.
The spin of the electron and positron are equal, and OPPOSITE. The particle-antiparticle pairs that fill the Vacuum are persistent, and dipoles can be induced in them. They do not self-annihilate. They are not detected because they are dipoles and cancel.
The electron-positron dipole consists of:
- a negative electron and a positively-charged positron
- opposite spin on the two ends of the dipole
The constituents of the Vacuum can be manipulated (dipole stretch induced, or dipole stretch removed) but the only way to do so is with coherence conditions imposed on the atoms of a matter object. Coherence imposed on piezo materials by a maser is one way to alter the Vacuum coherently.
The Vacuum very rapidly quenches any attempt to alter its conditions unless the attempt is coherent. Artificial gravity can be produced in this manner.
.
Sir your books helps lots of student and awakened love towards physics
But in changing world I request you to creat a new master piece on platform of TH-cam.
In Science you are never wrong! This simply means that this is the way by which you can't get right solution. This explores our mind to make new possibilities and challanges to look into that problem in more effective way. Inspired by Thomas Alva Edison. Respect for both of the teachers. We are learning a lot from you all. 🙏❤️
You are absolutely great sir....
Every one has different approach of solving questions....
I am satisfied with H C Verma's solution. I never find any wrong with it. Thank you H C Verma Sir
Nature and it's beauty. It will work as it is. Respect for both Prof. HC Verma and Prof. Walter Lewin
Sir after watching your videos and your explanation simplicity my physics fear gone away. Now I work hard to rock in physics.🙏🙏
Genius teacher and my inspiration to pursue research in physics instead of engineering in a company.♥️♥️♥️♥️
😁
Sir if earth moves at 1675km/hr and if we moved a car at 50kmhr at the same direction so technically its speed will 1725kkm/hr ???? Please answer the question
@@dhruvmishra2000 it depends from which frame you are asking if you are asking from a stationary frame outside the earth then it will be 1725 but if the frame is inside the car then speed of car will be zero if the frame is outside the car and on the earth then it will be 50km/hr.
So nice.
@@dhruvmishra2000 no bro car is moving on surface . Of earth so technically tangential vel of earth gets vectorilly added to it but in the frame of outside earth
Thank you sir , when in a video i saw this question, i guessed a bit about lenz law but from this video i got conceptual clarity. Thank you sir. Please keep making more such videos.
Can someone acknowledge the fact that I studied this entire chapter just because of this controversial problem.
👍🏻
yeah yeah.... we all did the same...lol 😂
@Suvarnim Jain 10th lmao
Physics is a royal subject which wise people can only understand the truth behind it. One among the people is Prof. WALTER .L, who is so wise enough to point out mistakes of others.
I happen to came across a quote by Richard Feynman that "science is the belief in the ignorance of experts". Which is to say that there is no scientific authority, humans can all be wrong at one thing or another and that's ok, because remember the moment of being wrong is the moment of humbleness and more importantly learning.
sir thank you very much for making physics interesting (interesting to pahile se tha par aapne usko ek feeling de di)
Sir Your solution is correct no one can prove it wrong conceptually 🙏🙏🙏
What the hell?
Very very simple and to the point explanation sir.
India's pride HC Verma sir
Thanks
We proud Sir that we connect Both great Scientists H.C. Verma & Walter Levine.🙏🏻🙏🏻
Literally respescted sir, even in generation of online mode due to corona virus it really helps to fall in love with physics is only possible by your these intresting sessions of physics....inspiring for us🙏🙏
All the best. Thanks.
@@hcverma2928 thank you sir🙏
@@hcverma2928
Dear sir
Where I will ask my new doubts ?
Can you please tell me !!!
Thank you sir, for clearing the misconceptions on this topic, as you always do. 😀😀
So nice of you
@@hcverma2928 love you sir!
You are best sir
Awesome Explain.. And Awesome update.. 👍💓💯🙏
So nice of you
And now.... Sir Walter lewin denied this solution as i have seen 23 minutes ago his solution.
But i hope as a professionals of physics, you both will get a clear thought process about its solution.
A DISPLAY OF A VERY POOR CONDESCENDING ATTITUTE BY WALTER LEWIN! It all starts with his statement "I doubt even Prof Verma can answer this problem". Then goes on to call the solution "blatantly wrong" " and "it is wrong physics" in a poor taste.
Dear HC Verma Sir, thanks for all ur contribution to the student community.
Lewin just cherry picks on one phrase of HC Verma of the current being in the material and then calls the complete solution "blatantly wrong" and says that "it is wrong physics" where in fact most of the solution is absolutely correct. It's just that HC Verma should have used the language "E and B go to zero deep inside the superconductor and he could have described the distribution of current inside it but it goes far beyond the scope of JEE (the question said it was for JEE). The bigger irony is that Walter Lewin who calls Verma's solution wrong himself does not understand superconductivity and he so instead of using the phrase " deep down", says that E is zero everywhere inside .
LEWIN himself makes TONS of mistakes in his question video...
Zeroeth of all, he calls it a JEE problem...Seriously? Superconductivity?
Now comes the first point. Lewin says that there can be no electric field inside the superconductor. "Blatantly Wrong!!!". Ever heard of london penetration depth?
Lewin says in the solution video that the current will flow on the surface of the superconductor. He says that there can be no current inside the material. "Blatantly Wrong!!!" Surface by definition has zero thickness which will blow up the areal current density. The truth is that the current does flow inside the material but near the boundary of the material(near the surface, not on the surface!), significant amount of which is upto the penetration depth. Only deep down the superconducting material, B and E go towards zero.
This penetration depth can be of the orders of nm to um or even could become very very large if you happen to go near the critical temperature.
Second point, Lewin says "the beauty is...faradays law...creates an emf...an electric field..just OUTSIDE the superconductor"....LOL... " Blatantly Wrong!!!" What do you mean by "just outside"?
Faraday's law holds for any hypothetical geometrical loop created anywhere in space. This is what HC Verma explains in his solution video and this is what Lewin needs to learn from him. And it is definitely clear now that you have not heard of 'penetration depth'. Current cannot propagate "outside" the material. The thing which Lewin and many others wrongly call a surface, is not a surface but a volume. In Lewin's words, HC verma's statement that current is there inside the material is wrong. Lewin also states "there cannot be any current in the superconductor".This is wrong! The current is definitely inside the material (LOL Lewin, where else the current could be?!). I again reiterate that current is not propagating on a surface but in a volume.
Coming to the second point, Lewin gives insufficient information regarding the external magnetic field. What if its magnitude is greater than the critical magnetic field? The superconducting state will be lost.
Third, Lewin gives insufficient information regarding the thickness of the superconducting wire. What if I use a thickness comparable to the london penetration depth of the superconducting material?
@@musicalbot9172 Reeeee
@@rohithninan8785 whats Reeee?
Best professor in the world 👍👍
You are the best sir 👍
Thank You Padma Shri HC Verma Sir. Love from Nepal🇳🇵❤️🙏
Ma comment herdai garda ysta comments ni bhetxu 😁😁
@@sandeepkarki4575 Chalo accha hey😂🙏
I love seeing this man smile
Thanks.
Prof HC Verma is correct in saying that electrical field inside the super conductor is zero. However, at the surface/boundary of superconductor the electrical field won’t be zero. This is the one thing Prof Walter Lewin *added*. In this case, current will flow on the surface of superconductor only.
On side note: I have never found a better book than concept of physics. It was this book that made me crack IIT JEE. Thanks.
Does it act like a topological insulator?
@@AsifShah-fi7oj By definition- it seems like. However, the way I think is that at the boundary of the superconductor- at one side conductivity is infinity and at the other side, it is close to zero. So at the boundary, conductivity can have anything between zero and infinity.
He is sooo humble and kind person I want to meet u sir once in my life And in physics anyone in this world not know completely they just guess with many assumption even Albert Einstein not believe in quantum mechanics but it is true physics is endless and their are soo many many things which are out of our imagination.
> Albert Einstein not believe in quantum mechanics
He did not believe in one particular *interpretation* of QM !
@@alexleibovici4834 he has a different perspective of quantum mechanics and when he doesn't believe in quantum mechanics interpretation we say that he was not believed in quantum mechanics he say that their is any mistake by us in very fundamental level of our understanding of universe
@@amansinghkarchuli1005
> when he doesn't believe in quantum mechanics interpretation we say that he was not believed in quantum mechanics
If we say that, than we are wrong ! It is because QM works very well, and Einstein knew this. He died in 1955, and by that time QM applications made big advances: in computing spectrums of atoms and molecules, even with relativistic correction, and also quantum electrodynamics (Feynman and others).
What he was against is the the Copenhagen interpretation of QM (it is the observer that creates the reality) and he believed that QM, being probabilistic, is not THE ultimate theory.
I recommend you Mario Bunge, for example "Philosophy of Physics", Ch. 5.
@@alexleibovici4834 thank you so much brother I am preparing for iit but I interesting in QM so I know a very little things about this, I want to share something which I found in ancient Indian books you know Vedas, Upanishads. In Upanishads the same thing IT is the observer who creates the reality is written and I am so shocked after studying this and in Vedas their is much more than this which today science proof and this is very interesting..
@@amansinghkarchuli1005
The idea that the observer creates the reality is called "solipsism"
This video can't be an ordinary video..
I can feel the presence of some energy.. ❤️
Sir although urs solution to this problem is wrong but u r too a human sir,aap legend ho sir.U are MODERN RP FYNNMAN OF THE WORLD.We all respect U and Walter lewin sir too❤️.
Sir wrote in hindi, shanka samadhan, WHICH MEANS: DOUBTFUL SOLUTION, HE WAS NOT SURE ABOUT THIS SOLUTION ! WOW SIR...
Sir you are one of the greatest teacher 🙏🙏🙏🙏
Thank you for the lecture, professor Verma.
I think your answer is better than professor Lewin's answer.
Thanks sir because of you and Walter Lewin sir, I fell in love with physics.
I am so Inspired by you sir...by so many achievements but you are so humble and no compare of your intelligence...I hope I will become like u one day ❤❤
thankyou so much sir you cleared a big misconception
sir love your way of teaching
Very informative lecture. Thankyou sir
It's lewin vs verma sir now no matters who is right but it's going crazy 🔥 we love both of them 😍
It's not 'vs' at all, few viewers are making it seem like 'vs'
@@shahnazwm it's prof hcv and prof Lewin
Hey man, stop writing Lewin 'vs' verma! It's a discussion between professors on a problem, not any kind of 'prove him wrong' competition!!!
U r right Walter sir is trying to show off otherwise there is no need to put a video that HCV couldn't make it
True Science and Idea should be appreciated. Science & Nature proves us wrong every now & then.
💕💕
Explanation simple and best as usual.
Just how physics is.
Still Love your book.
Sir Can the change in magnetic flux can be zero at the very INSTANT during the motion of the magnet? ( since information cannot travel above speed of light )
I feel it must not
Because magnetic field lines are infinite and are always present as ideal behaviour of magnetic fields so even on the infinitesimal disturbance on magnetic field would generate emf thus flux≠0 at the very instant
@@beenamorya1664 ellaborate plz
Honestly speaking this was quite easy question, seeing from a iit point of view... like if u have ur concept clear... this is a like a scoring question for u
@mahi jain ya i mean u say that after watching prof Lewin's video... and i never said jee adv is easy... and i am in class 12 prep for iit... i know about jee adv
@@parijatsutradhar can u tell my what is. Question they are debating for?i mean lewin vs Verma
@@achillesinvader3921 So there was a question (that came in the jee advanced exam), that asked what will happen when there is a changing magnetic field through a coil made of completely super conducting material (u can get the exact question in prof Lewin's channel)... so the controversy was that Prof. HC Verma gave a solution, which was later disagreed by Prof. Lewin...
U can check out his video... it is quite interesting
@@parijatsutradhar First of. All bro you are looking handsome in spec s and can u give detailed about this....because i am not geting his language
@@achillesinvader3921 First of all this is my school's requirement to have a profile pic in school uniform (which is horrible)
So coming to the question, it asked that if u oscillate a bat magnet in and out through a solenoid made of superconducting material, then will there be Electrical field, if no, then isnt it violating Faraday's Law. And secondly is there B field present in the solenoid coil... so u have to explain what is happening... the interesting part is there is a property of superconductor that even in electrodynamic condition, there E field inside the conductor is 0... but then it apparently disagrees with Faraday's law
Sir even your solution is wrong. We love u so much ❤️.
Great people learn from their mistakes. 👍
We Generalise a wire based circuit MOSTLY AS A ONE DIMENSIONAL WIRE with r=0 so it has no interior or exterior or the interior and exterior are virtually not present as if its a line with just 1 dimension.
Here we are taking a wire with finite radius where it has a external and internal space different from each other or as if radius of wire is not equal to zero.
prof verma did with the idealisation of r=0.
I think then it just becomes a thought experiment.
But Prof. Lewin did analysed the situation with a non zero radius .i.e the wire has a surface and then internally E=0.
I guess with the idealisation Prof Verma's solution is not wrong.
Sir aapne Walter lawin sir ko achha jwab Diya 😄
When??
Wht hpnd?
@@HangingQueen problem 119
@@RoyBoyLab in Walter Lewin lecture ??
@@HangingQueen check his channel .. problem 119
Good reply to respected Walter lewin sir
Professor Walter declared this explanation as a wrong solution and HC Verma sir accepted it as incomplete solution.
Can you pls tell me where he accepted it to be incomplete? Was it some comment on video or somewhere else?
@@musicalbot9172 in Walter lewins lecture
@@jeetendrasinghrawat6661 did he comment on walter lewins video?
@@musicalbot9172 nope , Walter lewin himself saw video in hc vermas channel when he came to know that hc verma had solved his question
@@jeetendrasinghrawat6661 read the comment carefully. It says "HC verma sir accepted it as incomplete solution". I am asking where did hc verma accept it as incomplete.....
And this Walter Lewin, he has a very poor condescending attitude. Calls HC Verma "blatantly" wrong when in fact he was correct for most of the part. He himself makes tons of mistakes in his question video himself and calls others blatantly wrong.
Sir I did almost solved this problem before you started explaining .👍
Sir u are really a Gem 💎 and also inspiration to me😌❤
Nice and clear gurujii
Sir your lectures and problems always create a great curiosity and imagination .you created such an indomitable spirit and interests for physics in us. you reach students through different platforms .you always make sure that quality lectures n education reach to every students to all corners .
Heartly thank you sir🙏
we will always be grateful to you and your contributions ❤️❤️❤️
Anyone after walten lewin's latest video?
TBH the solution is too convincing and doesn't seems to be wrong. First you learn extra stuff ad do your complete revision of EMI in 13 minutes. loved it..
Awesome concept ... Thank you for making this video...
Most welcome 😊
I think:
The current will be close to infinity so that there is a finite emf generated which satisfies j=sigma E. This current will create an incredibly high amount of counter force on the source of the magnetic field that is the magnet.The magnet will be very hard to move causing the emf to drop immediately and current will come down to 0.
I tried to think of the situation when the resistivity of the superconducting material tends to zero
Sir have replied to walter lewin sir problem.. he challanged Verma sir in his video
Sir I thought it this way:
If we try to move the magnet close to the loop, then the loop being made of a superconductor will compensate for the flux produced by the magnet by producing a current in the loop making net flux zero. But when the distance between the loop and the magnet becomes zero then infinite current needs to be produced in the loop which is not possible,so we can say that the loop will not let the magnet move by producing repulsive force.
Sir please make a video clarifying your side of explanation and address the issues pointed by Walter Lewin sir
Prof Lewin says that there will be a current on the surface of the superconducting coil but not inside it. The link to the video in which has posted this solution is th-cam.com/video/fGM5AtwEmuQ/w-d-xo.html
But he does not explain why no current inside the coil does not violate Faraday's law. As Prof HC Verma has emphasized, Faraday's law is applicable on any closed loop, even if the loop is intangible. If we want, we can consider a loop inside the coil. According to Faraday's law, an emf will be induced in that loop, which means an emf will be induced inside the coil. Then why is there no current inside the loop?
This exact case is mentioned in Sears and Zemnskys University Physics.
ok
@@hcverma2928 Sir!!! Thanks a lot for replying.
Sir very useful knowledge, but i have a request, plz try to demonstrate the practical experiment as well, it will bring clarity to understand the concept.
HC Verma sir and walten sir they are great scientist
i must say that Kota consist of huge minded prof. who teaches us in such a way that walter lewin sir found this question tougher,we Indians are at a level,that is actually differ in a large mass
2:23 , sound travelled before ( faster ) , then after work is done
I am in love with his book 🙏🏻
is possible to differentiate electric field generated by m.field or static charge .
Sir can you please elaborate that in case of conductor if opposition is incomplete but still opposition is there then why we are not accounting that incomplete opposite in calculation ?
Truely a genius.
Can you pl link it with Meissner effect and London penetration depth and type 1 and 2 superconductors.
Super helpful sir ❤️❤️❤️❤️
We have great respect for HC Verma sir
Towards the end you have said that when magnet goes away the current in loop should be such that it will increase the flux so how magnetic field in loop becomes zero. Since there is current so there should be magnetic field, isn't it?
Thanks
@@hcverma2928 Can you please give answer of question asked by Sachin?
@@kavan2908
Verma did not mean the net flux continues to increase such that it never goes to zero but the process(Lens Law) tries to keep the flux from the magnet seen by the coil from falling by INCREASING or adding to it with the flux produced by the induced current.
When moving the magnet into the coil, the coil sees the B-field and flux from then magnet increasing and a current is induced in the coil in such a direction as to create a flux to oppose and decrease the applied flux to balance it out to try keep the NET flux as seen by the coil from changing. When you pull the magnet out of the coil, the B-field and flux of the magnet are still in the same direction as before but now decreasing in intensity as seen by the coil. The current induced in the coil now REVERSES direction to create a flux to build up and aid the flux from the magnet as it is decreasing to balance to try keep the NET flux from further changing. This is a loosing battle and the net flux will eventually go to zero as the magnet is moved further and further away or flipped to reverse pole polarities.
GH
The magnetic field in the loop will be zero by the vector sum of bar magnet's magnetic field and magnetic field due to current loop.
th-cam.com/video/bZ6pZgAXRL4/w-d-xo.html
I believe in your approach
Sir please post a short correction video. It will be easier to understand from you 😇
Sir Walter Lewin sir asked this question in his last video sir that's why now everyone is asking this question
that is why I got mails from students requesting to talk on this.
@@hcverma2928 he take your name in his video.
@@hcverma2928 and tell you are wrong
Now this is answer to the question asked by prof. Walter👍