This website contains all my 94 course lectures (8.01, 8.02 and 8.03) with improved resolution. They also include all my homework problem sets, my exams and the solutions. Also included are lecture notes and 143 short videos in which I discuss basic problems. ENJOY!
Lectures by Walter Lewin. They will make you ♥ Physics. do u rthink benjamin fraklin did experiment of kite as it was high voltage. he might be died on the spot
I have to say this! Walter Lewin is the best teacher, i've ever had. Literally makes you love Physics. Isn't every teacher is supposed to have this quality (of making you love his subject)! He is a true inspiration..
thank you for Posting this! I have a better understanding of Lightning and coronal discharge now :) I have indeed seen St Elmo's fire on a metal fence post near my maple tree. Luckily the tree is unharmed as it occurs often before a bad thunderstorm. But I also live under high voltage power lines and have no lightning rod on my house.
Why does Walter Lewin have to touch the metal plate before touching the metal plate to the pan? Doesn't touching the plate get rid of the charge? Doesn't he want the charge to stay on the plate, so that it can then charge the pan? What am I missing?
Thank you for making these fantastic lectures available, I´m a little late to the party attending college in my thirties and the demonstrations are so much fun that my kids like watching them with me.
Being hit by a spark and hearing this tremendous shot without ear protection? Bless you, Mr. Lewin, for I'm afraid it wasn't your lucky day! Much love from Brazil! :)
During my studies, I have never seen such a great explanation of a subject as from professor Lewin. When I consider the fact that he even finds free time to explain additional questions in the comments after all these years, I am truly shocked. As I don’t like youtube (and other social networks) in general because of the commercial, boring and useless staff, I really appreciate that this time youtube and prof. Lewin can hand over their knowledge so we can make a world a little bit better. Thank you
The lecture was amazing!!!! i was sitting on the edge of my chair, enjoying the lecture thoroughly, about sparks and lightning! Thank you for so much of "phun with physics".
My physics teacher just reads a powerpoint and lets students use Chegg during exams. DURING EXAMS. Which indicates, to me, that he only cares about his image of being a good teacher as he passes students along who will make terrifyingly inaccurate engineering solutions to real-world problems. These videos are gold to me.
Professor Lewin is an absolutely inspirational educator :) I'm currently working a public science communication job, and hope to return to school and become a professor myself; These lectures are giving me loads of demonstration ideas, extraordinary perspectives on explanations, and best of all, I'm learning so many things I didn't know before. Thank you sir!
This is teaching in its purest form, hooking your audience, motivating them to aquire knowledge, and ending it with a bang, this lectures should be used as a guide to teach new generations how to teach. If most teachers did this, we all could have picked our craft and area of passion and expertice way earlier in life.
What a practical approach of learning, absolutely very interesting lecture..I am working as a physics teacher and I am learning from professor how to teach the students...
Teaching is really really hard task. It is a journey, and Professor Walter Lewin has shown us the true way to learn Physics. Thank you Professor for your lectures. It has been the most helpful.
52:06 "a small bloop, and since it's going to be very small, at best..." he said. "You have to be very quiet, otherwise you won't hear anything," they said.
+Onesockanda Song That was no bloop. I was drawing sparks from the Van de Graaff usig a share point and if students are very quiet they can hear the cracking noise of the sparks,
How did this guy suck me in so deeply and suddenly I now have have a wealth of understanding of why lightning hits the points of an object instead of the flatter portions?? Regardless of the complexities I had to restore in my brain, he runs through the logic PERFECTLY!! This guy is a GREAT teacher!!! 👍🏻😎👍🏻
I can't have enought of your classes Mr Lewin! (So, I bought your book :-) ) Thank you for sharing your lectures on internet, that way you continously are becoming a teacher for everyone who want to be your student, you are very generous!
Thank you professor for making these lectures available because most of us po folks don't have $27000 a year to run up a big bill. I would like to see your extrapolation into specific protection projects such as the ball of spikes that we Radio Engineers use on the top of radio towers to dissipate the electrostatic charge buildup over several seconds and prevent the initial leader from the ground and prevent most lightning strikes. I have always been a firm believer that education is a continuing process that you never finish until that final day.
Sir.you are a wonderful teacher. I like the demotration and practical experiment.shown by u in your all lecture. I had done my graduation in electronics and telecommunication.a long time ago but I still enjoy to learn concept of physics.from professor like u. Sir your theoretical and practical teaching both wonderful.thanku sir.
Dr walter lewin l hope that you read my comment l really love your way in physics you made me a scientist in physics , nowl have my frist PHD in physics.
Very good lecture. As a chemistry student I really endeavor having a better understanding of basic physics, which this lecture really is about. Thanks for putting these up on UA-cam. One interesting bonus fact: Lightnings produce a significant amount of nitrose gases which also contribute to the scent of a storm. Estimates speak of up to 10^9 kg of nitrogen per year being converted to nitrates this way
+Smick Smo Yes I know. Lightning produces NO and N02. Does it also N2O? THat would be "funny" as N2O is laughing gas. It is used in surgery and dentistry for its anesthetic and analgesic effects.
Lectures by Walter Lewin. They will make you ♥ Physics. I can’t believe you responded😁 I’m loving your lectures. One day when I am a grad student I will try to make my own lectures as interesting as yours are. You are a huge inspiration!!
I loved these class very much. Wonderfull stuff for students. I never had such a teacher to learn physics. Physics is fun and electricity is lot more fun.
what the hell man only 32 k views on such Quality video and 2M views on that 1000° knife idiotic videos. ..... why people are not taking advantage of technology Mann it really hurts
Because people are stupid and they don't care anything that doesn't affect them. But only people who can see potential for ex. scientists and some engineers are excited and they do really care theese things...
Rohit the USA is filled with liberal college graduates who are more interested in brain dead idiots, instead of something that is really educational. And they don't have the intelligence to understand what he is saying. Other words they are STUPID.
views number is not a criterion even for songs stupid song like decpacito has billions while other classical high level of lyrics music less than a milion
The best lectures that I have ever seen. Just a little more information regarding your lecture about breakdown voltage of the air. Depends on distance the breakdown voltage (BDV) would be changed not linearly. (for example 1mm could have 3kV BDV, and it does not mean 2mm would have 6kV BDV)
your welcome. I hope everybody (specially students) could see your lectures, because it changes the view of seeing the nature. Your lectures also give them the possibility to think about every thing they see in nature. To know for every behaviour there exists a reason behind.
This explains why MIT is one of the finest Engineering School in the world because of high caliber and finest professors and only top students are accepted.
The part I don't quite understand is, in eg. Denmark this (most of it) is taught in the advanced physics course in high school already. Not full electromagnetism, but electrostatics.
@@skuula electrostatics is taught in high school everywhere, electricity and magnetism is where the true difficulty lies which he didn't really get into in this vid
That's how you end a class....bang....Mr Lewin u r awesome...Thnx to technology(electricity,UA-cam n Ambani) ....we can also access such class from far off places....Thnx sir
Even after completing Masters In Physics I continue to watch because nothing in this world is better than Walter Lewin's lectures ❤️❤️❤️❤️. You are truly an inspiration.. ❤️❤️ Much Respect !
Hi Professor Walter, I'm a mechanical engineer student from Italy! My physics professor during one of his lectures gave us the exact same demonstration about the different distribution of charges on smaller radius corners. He eventually told us at the end of the lecture, that the demonstration is fundamentally incorrect, and that there is a profound CONCEPTUAL ASSUMPTION (no wrong calculus) we made that is profoundly false.. but he then said that, despite that wrong assumption, that model works pretty well at explaining why that happens. He then gave us the task to find the wrong assumption we (and you) made... what would you say about that sir?
Sir I have a question. A cylindrical capacitor charged with +Q on the inner conductor and -Q on the outer conductor has, according to the book and your P.1.b) E = Q/(2πεLr). This is the field for a Gauss surface encolsing the inner cylinder with +Q charge. However, the outer (hollow) cylindrical conductor has a charge -Q on its inner surface (its very thin but still the conductor has E=0 everywhere inside apart from the surface facing inside). If I take a hollow cylindrical Gauss surface with the outer surface inside the outer cylinder (E=0) and the inner surface in the space in between the two conductors shouldn't I have one more contribution to the Electric field due to the enclosed -Q in this gauss surface? Is the surface I took valid? The resulting field will be the same but without the factor of 2 in the denominator.
Thank you Walter Lewin. A Fantastic timeless lecture once again! Your passion for physics is contagious, unlike french mal-air. Where would you point me to study the photoionization potential of oxygen, nitrogen, and other atmospheric gasses. Since we know UV light can assist in ionization of gasses under the correct conditions, I'm trying to get an idea of how much shortwave (UV) light energy is required to efficiently produce ions with much lower potentials using a wire/plate type ionizer. Any input at all is very appreciated!
Thanks for a rapid reply! Your the best. I need to learn more before I can ask a proper question, so thanks for letting me know. Keep up your fantastic work.
ok. the audio is starting to freak me out to a point where I want to ask why all of a sudden the audio quality changes in short spurts. This time for this video it starts at 3:47. I would probably be very scared if I had like a drink or two and it was late at night since these concepts, physics and videos are so amazing and profound.
hello sir..its been a great pleasure watching your lectures..they don't only make me love physics more but cause sleepless nights thinking about what you taught and demonstrated..a question popped up listening to one of your lectures..Is it possible to talk in a supersonic aircraft which moves faster than the velocity of sound and if so,how???
+Shifaz Baig The air inside your supersonic aircraft stands still relative to the plane. Thus you can speak and hear without any problem. Remember the Concordia which was a commercial passenger plane?
Professor, in the experiment in 42:41 why does it produce sound some times without producing light? Is just an audio error or is there a spark, just that it's not strong enough for us to see it?
i am taking the same course at my university, thank u very much for making this accessible to anyone... the lectures in my university are so boring and the doctor who teaches us only reads from his papers soo I am studying this course using ur playlist even though I study in a different language thank the universe that u exist two questions that interest me are when were these lectures captured ? and until lect 6 were learning the same subjects so the rest of the lectures in this playlist are still relevant right ?!
@@lecturesbywalterlewin.they9259 thanks professor, I checked them out and yeah they look more similar to my course because I am studying electrical engineering , but still the lectures here helps me build an intuitive thoughts on problems and concepts so I think I will still watch them to build a good basis for the advanced material in my course. thanks for replying so quickly I really appreciate ur help
Sir I love physics but I don't like mathematics much. so is it necessary to be a mathematician first to love physics or to explore physics ? what should I do please tell me sir?
At 43:27, you mentioned that the Sharp Point drain current, I think because of the sharp point accumulated most electron and make electric field more strong than any other place, but if the electric breakdown doesn't happen, how the current reach to the sharp point from Ven De Graff, if electric breakdown happened, then it will have spark and light.
when.you scuff your feet on a carpet, you gain electrons and become negatively charged. If you then place your finger near a metallic surface, such as doorknob, an electric field develops between your finger and the doorknob. As your finger gets closer to the surface, the magnitude of the electric field increases. when it exceeds a threshopd of 3MV/m, the air breaks down,creating a small lightning strike, which you feel as a shock.Estimate the distance between your finger and a doorknob at the point you feel the shock.
Lightning discharge some kind of "step leader" discharge propagation phenomena is very very hard~. this is because of the multiphysics, maybe coupled with fluid, thermodynamically with electromagntics~. even simple problem only in the electrostatic case, the space charge problem makes you tired, or self field current->lorentz force
i want to ask two questions please. the first question, from where the electron in 9:06 comes from? the second question what will make the ions neutralized again 10:00? in other wards, how the ions will be neutralized again?
7:33 we know that the glass is positively charge. So when he touches the glass with pan, some charges are transferred to the pan. And when he touches it won't the electrons from ground come neutralise it?
The glass is an insulator, so little to no charge will be transferred between the glass and the metal pan. Instead, there will be induction, electrons from the pan will get to the bottom closer to the glass, leaving positive charges behind on top. When you touch the pan, electrons come from the ground to the metal pan because they are attracted by the positive charge that the pan has due to the induction. In that way, the pan was negatively charged through induction.
A more common type of electrophorus is that instead of using glass, styrofoam or other material that has more tendency to get negatively charged through rubbing is used. In that way the styrofoam plate would get negative, making electrons on the pan to go on top away from the styrofoam due to repulsion, leaving protons closer to the styrofoam. In that way, if you touch the pan you remove the electrons from the pan and they go from your finger to the ground, making the pan positively charged through induction. I find this type of electrophorus method more intuitive than the other method. Actually if you look on the internet for electrophorus charging, you probably won't find someone explaining the case where there is a glass plate (or another plate) that has more tendency to get positively charged through rubbing.
Sir , I am a student from India. I viewed all your lectures. It was a visual treat for me. Thanks for everything. I wish to do the assignments of 8.01 and 8.02. In 8.02 assignments you have written reading from Giancoli. Sir, can you please tell the exact name of the textbook and which edition it is? Because then i can track the pages and problem nos. as specified in your assignments? Again, for 8.01, you have specified reading from Ohanian. What is the name of the text book and the edition of Ohanian? Sir, please reply. It would be a great help if you can tell me exact name and edition of these text books? For 8.03 assignments, you have specified the full name of text books (A P French and Bekefi & Barrett (ISBN No. etc). Like that can you tell me details of the text book for 8.01 and 8.02. Thanks a lot for the lectures Prof. Lewin Sir. Take care Sir. Lots of love from India.
I did not understand how come current is being drawn from the Van de Graff to the ground through that sharp object without generating any visible effects ? Is it the displacement current , treating the air as matter with non zero susceptibility ? What is happening in between the sharp tip and the Van de Graff ? Will I get shock of I put my finger in between ? Kindly drain away this question from my mind by correcting me if I am wrong. Pardon my brevity Walter Lewin Sir ! Take my love Sir. I have learnt a lot from your lectures.
Sir Walter Lewin! I'm little confused about that you said 6:10 - 6:15. How is it possible that the surface is equipotential even though E field on that sruface is not constant? I'm looking forward to your reply.
I watched 6:10-15 and cannot add to the clarity of what I said. I syggest you watch it again. You lack understading of the meaning of electric potential.
Sir I have a Question: When we saw Discharges from VanDeGraff they seem to be a straight line discharge towards the other small ball grounded, then why lightning discharges seem to be in a zig zag pattern and why not a straight line pattern?
This website contains all my 94 course lectures (8.01, 8.02 and 8.03) with improved resolution. They also include all my homework problem sets, my exams and the solutions. Also included are lecture notes and 143 short videos in which I discuss basic problems.
ENJOY!
Walter Lewin is the best teacher i have ever had ......
Truly magnificent, Sir you really make me love Physics...
Lectures by Walter Lewin. They will make you ♥ Physics. do u rthink benjamin fraklin did experiment of kite as it was high voltage. he might be died on the spot
why do you keep touching the metal plate to witness the shock
your lectures made me love physics ❤.. " finally in your orbit mr. lewin"
Walter: THANK YOU! I really appreciate your work, and I know it's not easy to make these things accessible like you do.
I have to say this!
Walter Lewin is the best teacher, i've ever had. Literally makes you love Physics.
Isn't every teacher is supposed to have this quality (of making you love his subject)!
He is a true inspiration..
+Rainman 10 Thanks Rainman for your kind words.
thank you for Posting this! I have a better understanding of Lightning and coronal discharge now :) I have indeed seen St Elmo's fire on a metal fence post near my maple tree. Luckily the tree is unharmed as it occurs often before a bad thunderstorm. But I also live under high voltage power lines and have no lightning rod on my house.
Why does Walter Lewin have to touch the metal plate before touching the metal plate to the pan? Doesn't touching the plate get rid of the charge? Doesn't he want the charge to stay on the plate, so that it can then charge the pan? What am I missing?
@@raymondblake5765 I also can't figure it out..
@@raymondblake5765 I think he wanted to know if there was still charge on there, if not then he would continue rubbing the cat fur ?
Thank you for making these fantastic lectures available, I´m a little late to the party attending college in my thirties and the demonstrations are so much fun that my kids like watching them with me.
+Hallgrímur Steinsson It's NEVER too late to start loving Physics, and being in your thirties is an excellent age to start!
30 years old now. 8 years late to the party, though. 😂
@@CurrentlyObsessively Yeah 😂
Am i early in this party because i am only 17😂
Being hit by a spark and hearing this tremendous shot without ear protection?
Bless you, Mr. Lewin, for I'm afraid it wasn't your lucky day!
Much love from Brazil! :)
During my studies, I have never seen such a great explanation of a subject as from professor Lewin. When I consider the fact that he even finds free time to explain additional questions in the comments after all these years, I am truly shocked. As I don’t like youtube (and other social networks) in general because of the commercial, boring and useless staff, I really appreciate that this time youtube and prof. Lewin can hand over their knowledge so we can make a world a little bit better. Thank you
sir you are simply a legend ..
no classes of this generation can beat your style of teaching
The lecture was amazing!!!! i was sitting on the edge of my chair, enjoying the lecture thoroughly, about sparks and lightning! Thank you for so much of "phun with physics".
:)
Sir Walter Lewin is the spark that illuminates us the path to love physics.
Thanks to you i really love physics.
He is very good
My physics teacher just reads a powerpoint and lets students use Chegg during exams. DURING EXAMS. Which indicates, to me, that he only cares about his image of being a good teacher as he passes students along who will make terrifyingly inaccurate engineering solutions to real-world problems.
These videos are gold to me.
Professor Lewin is an absolutely inspirational educator :) I'm currently working a public science communication job, and hope to return to school and become a professor myself; These lectures are giving me loads of demonstration ideas, extraordinary perspectives on explanations, and best of all, I'm learning so many things I didn't know before. Thank you sir!
This is teaching in its purest form, hooking your audience, motivating them to aquire knowledge, and ending it with a bang, this lectures should be used as a guide to teach new generations how to teach.
If most teachers did this, we all could have picked our craft and area of passion and expertice way earlier in life.
What a practical approach of learning, absolutely very interesting lecture..I am working as a physics teacher and I am learning from professor how to teach the students...
Teaching is really really hard task. It is a journey, and Professor Walter Lewin has shown us the true way to learn Physics. Thank you Professor for your lectures. It has been the most helpful.
The end is very surprising! I enjoy the lecture a lot. Thank you, prof!
Glad you liked it!
52:06 "a small bloop, and since it's going to be very small, at best..." he said. "You have to be very quiet, otherwise you won't hear anything," they said.
+Onesockanda Song That was no bloop. I was drawing sparks from the Van de Graaff usig a share point and if students are very quiet they can hear the cracking noise of the sparks,
+Lectures by Walter Lewin. They will make you ♥ Physics. lol are you actually Walter Lewin? And I was referencing another part of the video
+Onesockanda Song Yes I am Walter Lewin. I run this channel.
+Lectures by Walter Lewin. They will make you ♥ Physics. Well it's an honor to talk with you, then
@@lecturesbywalterlewin.they9259 love you sir (from India) . I'm 16 and I've seen 8.02 and loved this😊😊
How did this guy suck me in so deeply and suddenly I now have have a wealth of understanding of why lightning hits the points of an object instead of the flatter portions?? Regardless of the complexities I had to restore in my brain, he runs through the logic PERFECTLY!! This guy is a GREAT teacher!!! 👍🏻😎👍🏻
You are so good as my physics teacher. I love ur work and your practical skills. So happy to have your lectures....
Great lecture, concept of electric potential really coming together very well now. Thanks, professor and happy recent birthday!
One of my hero’s. Shame I’m a chemist 🤣 but I absolutely love your lectures...thank you for sharing.
I can't have enought of your classes Mr Lewin! (So, I bought your book :-) ) Thank you for sharing your lectures on internet, that way you continously are becoming a teacher for everyone who want to be your student, you are very generous!
:)
Thank you professor for making these lectures available because most of us po folks don't have $27000 a year to run up a big bill.
I would like to see your extrapolation into specific protection projects such as the ball of spikes that we Radio Engineers use on the top of radio towers to dissipate the electrostatic charge buildup over several seconds and prevent the initial leader from the ground and prevent most lightning strikes.
I have always been a firm believer that education is a continuing process that you never finish until that final day.
honestly speaking this lectures are a master piece!!!Brilliant PROFESSOR LEWIN Brilliant!!
:)
Sir.you are a wonderful teacher. I like the demotration and practical experiment.shown by u in your all lecture. I had done my graduation in electronics and telecommunication.a long time ago but I still enjoy to learn concept of physics.from professor like u. Sir your theoretical and practical teaching both wonderful.thanku sir.
I admire you, professor Lewin. You are a great inspiration for me :)
Dr walter lewin
l hope that you read my comment l really love your way in physics you made me a scientist in physics , nowl have my frist PHD in physics.
Very good lecture. As a chemistry student I really endeavor having a better understanding of basic physics, which this lecture really is about. Thanks for putting these up on UA-cam.
One interesting bonus fact: Lightnings produce a significant amount of nitrose gases which also contribute to the scent of a storm. Estimates speak of up to 10^9 kg of nitrogen per year being converted to nitrates this way
+Smick Smo Yes I know. Lightning produces NO and N02. Does it also N2O? THat would be "funny" as N2O is laughing gas. It is used in surgery and dentistry for its anesthetic and analgesic effects.
I think all kinds of nitrose gases are produced by a lightnig strike. Even laughing gas.
I am stunned by the virtuosity of this teacher.
His students are very lucky!
If you are looking for a good physics lecture this is the best a lecture can get
"END IT WITH A BANG", quite literally 😂😂
Thank you so much! Voltage breakdown is so much more clear to me now! Also your experiements! So grateful for it!
Thank you Walter Levin, you are a great teacher!
:)
33:52 That's where I heard the term Corona first
yes bro but this corona is related to sun and light ; not to disease .
Live long pray for u sir. Excellent donation of knowldge for students from u. I appriciate u sir.
:)
9:49 this is one of the coolest things I’ve seen so far
:)
Lectures by Walter Lewin. They will make you ♥ Physics. I can’t believe you responded😁 I’m loving your lectures. One day when I am a grad student I will try to make my own lectures as interesting as yours are. You are a huge inspiration!!
the way you explain your lectures is incredible and i love it... and i m trying to give your examples to my students...
:)
I loved these class very much. Wonderfull stuff for students. I never had such a teacher to learn physics. Physics is fun and electricity is lot more fun.
:)
One of the best lectures I have ever had
33:53, today it's called COVID-19 discharge
Really useful lectures sir you are the best teacher ever born i can never forget any concept you taught me .
Thank you very much for sharing your knowledge with everyone.
Congratulations Sir on one million subscribers 😍😍😍
Thanks for clarifying charge area vs. Charge density. (I always wondered about that.)
what the hell man only 32 k views on such Quality video and 2M views on that 1000° knife idiotic videos. ..... why people are not taking advantage of technology Mann it really hurts
Because people are stupid and they don't care anything that doesn't affect them. But only people who can see potential for ex. scientists and some engineers are excited and they do really care theese things...
Rohit the USA is filled with liberal college graduates who are more interested in brain dead idiots, instead of something that is really educational. And they don't have the intelligence to understand what he is saying. Other words they are STUPID.
views number is not a criterion even for songs stupid song like decpacito has billions while other classical high level of lyrics music less than a milion
because 9 year olds aren't going to be watching college physics lectures???
His teaching will definitely clear our fundamentals..d ways he shows experimentally...its awesome....will greatly help in my jee prep
You made me love physics. Thank you so much sir.
Sorry ... It is necessary to put your finger on the electrophorus each time?
After watching this video, my iphone 6s converted into a iphone 5s..
Great explanation professor! Hope you have a good mood every day
:)
The best lectures that I have ever seen. Just a little more information regarding your lecture about breakdown voltage of the air. Depends on distance the breakdown voltage (BDV) would be changed not linearly. (for example 1mm could have 3kV BDV, and it does not mean 2mm would have 6kV BDV)
Thanks, I know
your welcome. I hope everybody (specially students) could see your lectures, because it changes the view of seeing the nature.
Your lectures also give them the possibility to think about every thing they see in nature.
To know for every behaviour there exists a reason behind.
Best teacher ever !
Professor Lewin, hope you're doing well! You mentioned here a memory when you were an ungraduate, what was your major if you don't mind me asking?
Physics major as undergraduate
Im watching your videos as if Im binge watching netflix series. My popcorn is ready, I got my energy drinkbnext to me. Now Im ready to binge watch.
Sir bless your education life you are the most successful teacher in the world
:)
This explains why MIT is one of the finest Engineering School in the world because of high caliber and finest professors and only top students are accepted.
The part I don't quite understand is, in eg. Denmark this (most of it) is taught in the advanced physics course in high school already. Not full electromagnetism, but electrostatics.
@@skuula electrostatics is taught in high school everywhere, electricity and magnetism is where the true difficulty lies which he didn't really get into in this vid
@@skuula Yeah I was also surprised that this was taught in an engineering class. This is very basic stuff.
That's how you end a class....bang....Mr Lewin u r awesome...Thnx to technology(electricity,UA-cam n Ambani) ....we can also access such class from far off places....Thnx sir
you have my respect sir, taking shocks for students is not at all easy
its alomost 2023 and this lecture still gives me hope that we wont get malaria.
Professor Lewin, I love your classes.
This was an amazing lecture! I couldn't stop repeating the last part with the spark gun! 😂
Even after completing Masters In Physics I continue to watch because nothing in this world is better than Walter Lewin's lectures ❤️❤️❤️❤️. You are truly an inspiration.. ❤️❤️ Much Respect !
Wow, thank you!
Thankyou so much sir love from india♥🇮🇳
Hi Professor Walter, I'm a mechanical engineer student from Italy!
My physics professor during one of his lectures gave us the exact same demonstration about the different distribution of charges on smaller radius corners. He eventually told us at the end of the lecture, that the demonstration is fundamentally incorrect, and that there is a profound CONCEPTUAL ASSUMPTION (no wrong calculus) we made that is profoundly false.. but he then said that, despite that wrong assumption, that model works pretty well at explaining why that happens.
He then gave us the task to find the wrong assumption we (and you) made... what would you say about that sir?
Sir I have a question. A cylindrical capacitor charged with +Q on the inner conductor and -Q on the outer conductor has, according to the book and your P.1.b) E = Q/(2πεLr). This is the field for a Gauss surface encolsing the inner cylinder with +Q charge. However, the outer (hollow) cylindrical conductor has a charge -Q on its inner surface (its very thin but still the conductor has E=0 everywhere inside apart from the surface facing inside). If I take a hollow cylindrical Gauss surface with the outer surface inside the outer cylinder (E=0) and the inner surface in the space in between the two conductors shouldn't I have one more contribution to the Electric field due to the enclosed -Q in this gauss surface? Is the surface I took valid?
The resulting field will be the same but without the factor of 2 in the denominator.
Probably the best lecture on voltage breakdown and lightning concept!!!! Loved the BIG BANG ending.
Soo practical. Greatest Of All Time
That blast at the end was golden.
Hats off to your efforts sir .
Thanks a lot
@@lecturesbywalterlewin.they9259 You replied me ,really i am so happy and going to complete all the lectures .
Thank you Walter Lewin. A Fantastic timeless lecture once again! Your passion for physics is contagious, unlike french mal-air. Where would you point me to study the photoionization potential of oxygen, nitrogen, and other atmospheric gasses. Since we know UV light can assist in ionization of gasses under the correct conditions, I'm trying to get an idea of how much shortwave (UV) light energy is required to efficiently produce ions with much lower potentials using a wire/plate type ionizer. Any input at all is very appreciated!
question is too vague - ask Quora
Thanks for a rapid reply! Your the best. I need to learn more before I can ask a proper question, so thanks for letting me know. Keep up your fantastic work.
ok. the audio is starting to freak me out to a point where I want to ask why all of a sudden the audio quality changes in short spurts. This time for this video it starts at 3:47. I would probably be very scared if I had like a drink or two and it was late at night since these concepts, physics and videos are so amazing and profound.
hello sir..its been a great pleasure watching your lectures..they don't only make me love physics more but cause sleepless nights thinking about what you taught and demonstrated..a question popped up listening to one of your lectures..Is it possible to talk in a supersonic aircraft which moves faster than the velocity of sound and if so,how???
+Shifaz Baig The air inside your supersonic aircraft stands still relative to the plane. Thus you can speak and hear without any problem. Remember the Concordia which was a commercial passenger plane?
51:51 the build up to that was purely artistic
Professor, in the experiment in 42:41 why does it produce sound some times without producing light? Is just an audio error or is there a spark, just that it's not strong enough for us to see it?
could be too faint or a discharge on another part of the vdG
Thanks, sir
What an amazing lecture. Thank you.
i am taking the same course at my university, thank u very much for making this accessible to anyone... the lectures in my university are so boring and the doctor who teaches us only reads from his papers soo I am studying this course using ur playlist even though I study in a different language
thank the universe that u exist
two questions that interest me are when were these lectures captured ? and until lect 6 were learning the same subjects so the rest of the lectures in this playlist are still relevant right ?!
2002 - try MIT's 8.022; it's more advanced - it's on MIT OCW and on edX
@@lecturesbywalterlewin.they9259 thanks professor, I checked them out and yeah they look more similar to my course because I am studying electrical engineering , but still the lectures here helps me build an intuitive thoughts on problems and concepts so I think I will still watch them to build a good basis for the advanced material in my course. thanks for replying so quickly I really appreciate ur help
I hope you discuss ozone hole and how can we protect our plant and so on in a lecture
Sir, at 44.31 ,why can't we see the flash though their is a discharge through that sharp point?
you are such an amazing Teacher!!!!!!
Thank you Professor Lewin.
Sir I love physics but I don't like mathematics much. so is it necessary to be a mathematician first to love physics or to explore physics ? what should I do please tell me sir?
At 43:27, you mentioned that the Sharp Point drain current, I think because of the sharp point accumulated most electron and make electric field more strong than any other place, but if the electric breakdown doesn't happen, how the current reach to the sharp point from Ven De Graff, if electric breakdown happened, then it will have spark and light.
That girl at 20:38-20:41 seems absolutely ecstatic!
Perhaps she is taking in the knowledge via acoustically. Where is she in life now?
At the end...OMG moment 😂
😱😱😱😱😱😱😱😱😱😱🤯🤯🤯🤯🤯🤯🤯🤯🤯🤯🤩🤩🤩🤩🤩🤩🤩🌟🌟🌟🌟🤣🤣🤣🤣🤣🤣🤣🤣🤣
is there Nobel prize for teaching?
Sadly no.
when.you scuff your feet on a carpet, you gain electrons and become negatively charged. If you then place your finger near a metallic surface, such as doorknob, an electric field develops between your finger and the doorknob. As your finger gets closer to the surface, the magnitude of the electric field increases. when it exceeds a threshopd of 3MV/m, the air breaks down,creating a small lightning strike, which you feel as a shock.Estimate the distance between your finger and a doorknob at the point you feel the shock.
A life devoted to teaching physics.
Lightning discharge some kind of "step leader" discharge propagation phenomena is very very hard~. this is because of the multiphysics, maybe coupled with fluid, thermodynamically with electromagntics~. even simple problem only in the electrostatic case, the space charge problem makes you tired, or self field current->lorentz force
Sir why does current last only for a short period during sparks.
Excellent lecture Sir 🙏🙏🙏🙏🙏
Keep watching
But for the pointed surface, from where do we consider the radius? What can be a more generalised mathematical proof?
i want to ask two questions please.
the first question, from where the electron in 9:06 comes from?
the second question what will make the ions neutralized again 10:00? in other wards, how the ions will be neutralized again?
7:33 we know that the glass is positively charge. So when he touches the glass with pan, some charges are transferred to the pan. And when he touches it won't the electrons from ground come neutralise it?
The glass is an insulator, so little to no charge will be transferred between the glass and the metal pan. Instead, there will be induction, electrons from the pan will get to the bottom closer to the glass, leaving positive charges behind on top. When you touch the pan, electrons come from the ground to the metal pan because they are attracted by the positive charge that the pan has due to the induction. In that way, the pan was negatively charged through induction.
A more common type of electrophorus is that instead of using glass, styrofoam or other material that has more tendency to get negatively charged through rubbing is used. In that way the styrofoam plate would get negative, making electrons on the pan to go on top away from the styrofoam due to repulsion, leaving protons closer to the styrofoam. In that way, if you touch the pan you remove the electrons from the pan and they go from your finger to the ground, making the pan positively charged through induction.
I find this type of electrophorus method more intuitive than the other method. Actually if you look on the internet for electrophorus charging, you probably won't find someone explaining the case where there is a glass plate (or another plate) that has more tendency to get positively charged through rubbing.
13:30 sir if we had such perfect plates then from which point exactly would the spark happen since the E field and charge are same everywhere
esta genial Walter, saludos desde Santiago de Chile.
Sir , I am a student from India. I viewed all your lectures. It was a visual treat for me. Thanks for everything. I wish to do the assignments of 8.01 and 8.02. In 8.02 assignments you have written reading from Giancoli. Sir, can you please tell the exact name of the textbook and which edition it is? Because then i can track the pages and problem nos. as specified in your assignments? Again, for 8.01, you have specified reading from Ohanian. What is the name of the text book and the edition of Ohanian? Sir, please reply. It would be a great help if you can tell me exact name and edition of these text books? For 8.03 assignments, you have specified the full name of text books (A P French and Bekefi & Barrett (ISBN No. etc). Like that can you tell me details of the text book for 8.01 and 8.02. Thanks a lot for the lectures Prof. Lewin Sir. Take care Sir. Lots of love from India.
I did not understand how come current is being drawn from the Van de Graff to the ground through that sharp object without generating any visible effects ? Is it the displacement current , treating the air as matter with non zero susceptibility ? What is happening in between the sharp tip and the Van de Graff ? Will I get shock of I put my finger in between ? Kindly drain away this question from my mind by correcting me if I am wrong. Pardon my brevity Walter Lewin Sir ! Take my love Sir. I have learnt a lot from your lectures.
No Doubt...after watching these lectures, I have lost interested in taking lectures from my university professors
can anyone tell me the significance of his batch stick to the shirts he wears in his every lecture?
so you can determine the smoothness of a sphere by calculating how much charge the sphere will accommodate
not directly, but yes
He says:
"Corona Discharges"
Everyone after 2021:
~~STRONG FLASHBACKS~~
Who created that marsh gas at lobby 7
Why are you touching with your finger during electrophorous process?
Sir Walter Lewin!
I'm little confused about that you said 6:10 - 6:15. How is it possible that the surface is equipotential even though E field on that sruface is not constant? I'm looking forward to your reply.
I watched 6:10-15 and cannot add to the clarity of what I said. I syggest you watch it again. You lack understading of the meaning of electric potential.
@@lecturesbywalterlewin.they9259 I really appreciate, I have to understand deeper in this case. Thank You:)
Thank you so much sir . For your contribution in education
Sir I have a Question: When we saw Discharges from VanDeGraff they seem to be a straight line discharge towards the other small ball grounded, then why lightning discharges seem to be in a zig zag pattern and why not a straight line pattern?