8.02x - Lect 3 - Electric Flux, Gauss' Law, Examples
Вставка
- Опубліковано 2 чер 2024
- Electric Flux, Gauss's Law, Examples
Assignments Lecture 1, 2, 3, 4 and 5: freepdfhosting.com/2cb4aad955.pdf
Solutions Lecture 1, 2, 3, 4 and 5: freepdfhosting.com/75b96693f2.pdf - Наука та технологія
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. Thank you very much for uploading these videos and files, they are really fantastic and interesting lectures. :)
What website? And where are the homework problem sets?
THe homework assignments, exams, and the solutions and also my Lecture Notes are posted below the video thumbnail as pdf files.
Wow. Your lectures are just wow. Thank you very much for uploading these
Thanks for your kind words
Wow this guy is a beast. No wonder MIT students are so good. They have the best teachers.
He is not best but is appropriate to study from. Other's are mere crammers.
@@gurnaj5423 he's the best he makes u love the concept. Period.
@Kimmy Jonggy best is an opinion, at least share yours if you disagree bruh
One of the reasons, yes. But also the facilities and the innovation-driven spirit of MIT. The institute seeks to push forward the STEM field. Sadly many of our Schools don't have that spirit.
That’s what you (are supposed to) pay for
Best teacher cannot exis.....
Walter Levin: hold my van de graaf generator
Watching 8 years later.... 😊😊 Still all concepts cleared. Prepared for JEE 👍👍
Jee 2023/24?
@@7clouds567 maybe 2024.....
I can't believe that I am understanding physics but also loving it.
Thanks for uploading it.
Dr. Lewin, I just wanted to thank you!
I'm an aspiring EE and my professor for physics 2 at my community college goes through a chapter every 40 minutes. No demonstrations, skips over half of the slides and then doesn't really cover the ones he sticks on.
Your lectures are a great resource and make physics more fun to learn!
Before this lecture: I think I should leave physics
After: I should do research on physics
great.
🙌🏼
Yeah!
😄😄 very good
Same
Hi Dr. Lewin. I never get to like physics in my whole school life. Your lectures are so Articulate, patient, organized that it really glue me to the chair for 50mins. and more. Danke shune...sorry for wrong spelling.
+jessica galen Hi Jessica, I am not German, but it's nice that you tried German. shune ==> schon with an umlaut on the o.
In Dutch (I am Dutch) "veel dank" or "hartelijk dank".
@@lecturesbywalterlewin.they9259 Sir Lewis u r a great teacher of physics
@@lecturesbywalterlewin.they9259 i can't believe...being the brand teacher of physics ..u still reply to our comments sir.....hatts off 🙏🙏🙏......u r too grounded at the same time u r extraordinary brilliance.......hoping that i could ever get ur blessings
If I had Walter Lewin as my Physics teacher, I would not be an artist now. I don't know if it's a good thing or not, but now I work as an art teacher. And I usually put physics into the concept and theories, because art contains physics. the color theory, the material, structure, everything is connected to physics. Thank you Walter Lewin for this amazing lectures.
❤❤❤
I am preparing for jee....I've never understood anything better before this 😍
I really want to meet you sir! You are just amazing 😀
Me too brother
meet him ASAP. he may leave any time soon.
@@AlphaMan101 true though :(((
Any class 12 students here?
Yes
Yes me 😊
Yup
PW OP
BSC student here who is supposed to be doing MSC 👋
Mr. Lewin
Thank you so much for these very interesting and frankly amusing lectures!
I'm only a high school student (16 years old) but in my school we don't conduct experiments in any way, shape or form, unlike you do here. That's one of the many reasons I'm watching 8.02 right now. And l find it really glorious and intuitive to watch you explain everything so explicitly and practically.
You are a great professor. Thanks!
I'm 16 and I'm going to college.. most of my classes are super easy but I didnt at all understand physics II until I started watching these. Thank you so much!
Thank you, Professor Lewin. I still get something new ( and of course refresh my knowledge about electromagnetism) by watching your lectures even if I DO believe that I am good at electrodynamics.
Prof. Lewin, I learned about your lectures when I was still in high school and now I'm still watching them as a graduate student albeit in mathematics. Thank you for never failing to inspire.
Thank you sir 😊
You made me fall in love with Physics.. ❤️❤️❤️
Physics is ❤️
Love from India 🇮🇳
I absolutely loved that demo with the ping pong ball showing the strong electric field between the plates. You could even see it sparking sometimes!
0:20 Flux and electric flux, explain dA, n roof, closed surface...
Prove Gauss’s Law, simmetry
13:40 some examples
1. Spherical symmetry (how to choose closed surface, symmetric arguments, some amazing results, E(r) graph, coulomb law vs gauss law, 1/R^2, point charge at centre~ Newton gravitational Law)
24:00
2. Flat horizontal plane (3 conditions to choose the Gauss Surface: parallel, perpendicular, d)
=> an amazing result (1 plane/2 charged planes) , maxwell’s Publication.
- an amazing experiment with Van der graff and infinite plane => Extremely interesting
41:00 experiment: The Electric field inside the spherical charged is zero
46:50 experiment: 2 charged planes (very strong EF inside 2 planes)
41:30 Guy with weird look on his face
Hello professor, you have always been my source of knowledge in physics since 9th grade. Thank you for your amazing lectures and I have never seen a person more passionate for physics as you are !!!
This is really honor to sit in his class!
I envy you!!! But i am also so grateful beacose these lessons are online. it is a great work for the world, especially for us who did not have access to quality education!!
In my high school classes my teacher used to teach me physics in a very cool way but after two years i changed my school and now my physics teacher is making physics very boring (just using maths) . So i came here to enjoy physics ❤️
Can a teacher be any better than him ? Thank you for sharing these amazing lectures with us too sir!
Thank you very much, Professor Walter Lewin. I'm an international student at your Alma Mater in the Netherlands (TU Delft) and I just got the result of the exam "Physics for Mechanical Engineers". Your amazing lectures helped me not only to pass the exam but also to digest and understand the importance of physics in my future career. Thank you a lot.
I was struggling so hard to grasp the physic concepts since my professor basically only skimmed over the material. UA-cam has been a great help and this professor makes the concepts easy to understand. Kudos!
Analytical explanation of the Gauss's law step by step with demonstration, grand lecture Professor Walter Lewin 👏👌👌👌
These are great. Thank you for your dedication to teaching and making physics fun and understandable
Excellent way of making physics so simple... Sir i have been watching your lecture 6 years now... Whenever I watch any of your lecture feel like stick to it forever... Thanks a lot for making world to understand physics so simple way... 🙏👏💐🌷
I am so grateful for these lectures. I understand everything so much better, especially with these fantastic demonstrations.
I used to love physic. My collage teacher made me hate physic but for that teacher's exam, ı am studying with your videos and ı started to love physic again. Thx you :)
WONDERFUL LECTURER, WONDERFUL LECTURE, THANKS MANY TIMES
No fake enthusiasm no fake reaction everything was natural and peaceful great style of teaching concepts.
Thank u for your great lectures.Really your lectures made me love physics and today i suggested my freinds to watch your videos lectures because i am sure that they will also start loving physics after watching.
now physics is no more boring for me thanks a lot professor Lewin
you are very welcome!
You are a great teacher, thank you for sharing your lectures!
Sir thanku so much for providing such amazing lectures to a poor student at free of cost...
Learning this right now in high school. This is a huge help. Thanks professor Lewin!
I always knew what electrix flux was (like the defination and the math behind it) however I never knew how to apply it in later concepts and studies, after watching this lecture I have finally understood what electric flux is actually supposed to solve. Thank you so much
Oh! I wish I could have such an amazing teacher here in India coz In India most of teachers would only concentrate on completing syllabus they don't care about student's interest ....god please bless me with such great teachers
Come on bro....he is the teacher of world no.1 University
Asslamoalikum sir I m from Pakistan and I really likes your video keep it up sir
Love from India . Your are such a great legend of teaching physics. Any one will fall 😍 in physics# sir WL.🙋🙋
Wish we had teachers like him.. His enthusiasm makes you wanna learn
42:07 "...and since I have to get inside, I need an opening ."
Truest words were spoken;)
Thank u sir your lectures are amazing. I am just of 14 and these helped me a lot
What I love is how you challenged the students to figure out the flat plane E field.. I tried it out for myself, and because of the big hints you gave I got the same equation luckily! :) awesome lectures
For those who didnt understand the 45:12 concept as he is connected to ground he transfers some electrons from ground to the charged plate which is not perfeclty charged in order to neutralise all positive charges in that plate and hence increase the negative charge of the plate for his perfect experiment....hope it helps
Great lecture! Thanks Dr. Walter Lewin! Its my winter break, and I just wanted to learn some Physics for fun!
Im in the 12th grade.and it really helped to understand this concept thank you😍😊
He is a blessing for us who always got scary Physics teachers...
Amazing!!, I´m from Brazil and I´m enjoying very much the lessons
I've never seen anyone like you in physics before. You have given us incredible information . Thank you for the lecture . Hello from Hacettepe Universty🙂🙂
Wow, thanks!
God is good all the time! Thank you Sir for this incredible playlist ❤
bro i love you. you have a god given gift to teach. wowzers. those experiments at the end made everything you spoke about before click so perfectly.
thank you
Hi Dr. Lewin. I am watching your lectures from the very beginning ( starting from 8.02 and then will move to 8.01). I am watching these with the aim of scoring full in my this year Medical entrance test 2022 (Pakistan, I am from).I have a fear of Physics in me, I want to convert it to love for physics because in order to become proficient in Human anatomy (important for medical profession) you need to be in love with Physics, Chemistry and Biology altogether. My exam is somewhere in October/November. Watching YOUR lectures along with focusing on book, will let you know at the end of my last video(your last lecture, obvio) that at what level I feel I am interms of Physics at that time.
Good day to you!!
Hey in in junior high and ur really inspiring me to do physics in college 😁
I really loved your lesson! I learned a lot, I wish I could have such an amazing physics class here in brazil! Thank you, I'll definetely watch more of your videos later.
+Abel Figueiredo wonderful
I wish the same! but i am so thankful for this videolessons! It is a great oportunity to understand and love physics as it sould be. Greetings from Paraguay.
i can't express how benefit this lectures for me. Ive had always had struggled with electrodynamics but this is really enjoyable
thank you walter lewin ,i see you as one of the greatest scientist
:)
I thought Gauss is just: what comes in comes out. But it is beautiful, that E*A anytime keeps the same (just becaus it is proportional to 1/r^2) without a charge in a closed surface.
By the way, when I am not motivated for school, I am always looking forward to watch your lectures when I have time. Geat thanks for publish them.
I really like your videos sir i dnt knw about your videos but the sir from lighthouse channel has suggested in almost his every lecture about your videos and i just loved it....Thank you so mch for being an amazing teacher
:)
2019?
In last his greatness was wearing an egg, now a doughnut, intuitive.
A bagel, I think
Gracias profesor Lewin por publicar sus clases. Que agradable verlas
This syllabus is congruent to class 12 syllabus.......very excited...we xqn learn academics by an extraordinary teacher...#hatts of 4 u dr.lewin sir....for making our childhood awesome
Great
thankyou so much sir for making me fall in love with physics❤️
Thank you Dr Lewin for posting your incomparable Physics lectures.
:)
sir you are the the determinants of my stay in physics department of a Nigerian university
Sir you are most excellent and finest teacher of universe ....a lot of love from India
Hello, professor. As a high school student, I have trouble understanding exactly what symmetry arguments are. I have done several google searches but nothing worthwhile came up. How can I familiarise myself with the concept? Is it in Maths or Physics? And I know that you've heard this from millions of students already but thank you so much for these lovely lectures. I hope you are having a nice day!
ask google or watch my 8.02 lectures on E-field using Gauss' Law.
I would definitely say at this point Calculus 3 would be very useful, and he maybe skipped a couple steps when discussing Gaussian surfaces assuming you would understand what he meant by choosing what the surface should be. Also, I think the flux explanation leading into Gauss's law needed a little more to it. As for symmetry, it would be helpful once you've worked through the math to follow a textbook and do the examples and view online solutions.
don't over due the learning curve. you need to fully understand trig and algebra to understand what he means by symmetry. The radius is the same distance along the surface of the circle with radius r. because of this it does not matter where on the surface you relate the electric field to AS LONG as the charge is uniformly spread on the surface. This is because a sphere's surface is the same distance to the origin with respect to whatever radius you assign it.
and Geometry. As fundamental as people make these classes seam, they are really the foundation of everything in physics. without basic understanding of such concepts you will only set yourself up for dissapointment. step by step.
I am learning about this now in my lecture class and it's nice to bounce back between my professor explaining it and you explaining it. My professor went to MIT as an undergrad before you started teaching in the 1970's. He is excellent at explainable things and emphasis's the concepts much like yourself professor : )
:)
I would just sit for 24hrs if I had a teacher like you!!!!!....LOTS OF LOVE FROM INDIA SIR!!!!
I am studying for my Physics 2 final and your lectures had help me all over the semester. Thanks! Such an inspiration. Thanks from University of Puerto Rico at Mayagüez, from a Chemical Engineering student ☺️
thanks for your kind words
No wonder he teaches at MIT! He’s a great man!
Or vice versa
Now we don't need to get into MIT to enjoy these leactures. 😊 hope to see more physics leactures
In one word... you’re a legend professor
you are even more than an amazing physics teacher, I think, on earth, after getting your few lectures, I realized that you are truly the best physics teacher on earth at least, cause now I literally begun liking physics a lot, thank you for helping millions of students to do well in physics, thanks once again, respected professor.😀😀
Wow, thank you!
Sir, you know if you take a very large uniformly charged hollow sphere, the E field is independent of the distance if you are relatively close to it.
Its value can be given by sigma/ε zero
Same as two planes with same charge.
I discovered that while revising this chapter 😊
This because at very short distances the charged hollow sphere looks like a flat plane.
no one is going to comment on the bagel pin?
He was wearing an egg in lecture 2. Nothing new here.
hate speech ,,,,,reported !!
my mom works at youtube
M M
M M M M
M M M M
M M M M
M M M
I'm assuming that since bagels are high in iron he's planning to use it as the core in a toroidal transformer
You did, so...
it's 2022 now still using these videos to help myself learning thank you thank you thank you for providing such great material for free
Thanks a lot 😊 you are awesome sir
It is hard for us to watch experiments like this to understand theories it is so helpful and it has increased my interest in physics 😊
Wow he just linked Fluid dynamics with electric fields. Amaze ♥️
:)
@@lecturesbywalterlewin.they9259 Noone is like you sir, but my physics teacher is also as amazing as you. He also connects the theoretical physics to practical physics. He is super expert teacher for Jee Advanced exam.
@@lecturesbywalterlewin.they9259 He taught me gauss law, electric flux, fluid dynamics, neucleus, work-energy-power, gravitational force, totational motion, centre of mass and many other concepts.
@@lecturesbywalterlewin.they9259 He is your small brother
Sir, could you explain why Gauss's law holds true for non spherical, irregular surfaces as well? I cannot find a good explanation of it anywhere online. Thank you!
It's 1 of Maxwell's 4 equations. I suggest you ask Google whether Gauss Law can be derived or proven.
Woow ... What is so difficult to my lecture to illustrate this...coz Theoreticaly it's hard to understand all these with dimensions and drawings, only practically will save the lecture🙏❤️ Thank you Sir
When i started studying electrostatics then i didn't understand why we choose infinitely large plates well now i got the answer no teacher told me about that here in India
Thank u sir
Gradually clearing all my doubts
professor Lewin , I love physics too much . And your lectures are also extraordinary full with tremendous tranquility . I am an Indian and a big fan of you . I will be greatful if you give some advice how to be more broad minded in physics . thank you.
why did you mention you are an indian?
@@THEMRblackboy7thst what's the problem in mentioning it?
@@THEMRblackboy7thst is that bad?
Nationality is pointless as long as you like physics. It's unnecessary to mention it.
I like how the spherical charge model can be understood with gravity. Curious that if gravity was electric in nature that we would likely experience the same results On a spherical plane such as the earth.
You are making physics very easy for me in 12th grade thank u sir
Lots of love from India 🇮🇳🇮🇳
44:57 electrons are going from the metal plate to the ground when you touch it, leaving a net positive charge on the metal plate. The important thing to note here is that the metal plate is maintaining contact with the glass when you are touching it, if you pick up the metal plate and then touch it it will lose it's charge
Sir,
The first thing I want to know that in the last experiment, where a ball oscillates in between the plates, if, the neutral ball was held at first in between the charged plates, without touching any of them, and then allowed to move, would that remain at rest or somehow will start to oscillate? Does Earnshaw's theorem have any application here?
The second thing, while touching the above end of Electrophorus to transfer the negative charge to the earth, were you wearing shoes? Then how do the charges move to the ground?
I will be pleased if you answer these doubts. Respect and Love from India.
yes with electrophorus you can wear shoes.
Sir your lectures are amazing. I have a doubt - in the experiment in which you showed there is no field inside a hollow sphere, why did you keep touching that plate before placing it on the sphere?
google electrophorus
Thak u sir
I was interested in physics in my childhood but when I was in school physics classes were boring my interest was lost in physics. but when I saw your lectures now I'm in love with physics .
Ok you might not read this but you changed my life.thank you sir ❤
Hello Sir, what would be the position of charges if a closed conductor having a cavity is placed in uniform electric field?
the net charge on the conductor will be zero. charge density at the surface (both + and --) will depend on geometry. The conductor will be an equipotential everywhere - at its surface, inside the conductor and inside the cavity.
@@lecturesbywalterlewin.they9259
Hello sir
I have a doubt
Why can't aether exist as explained by Huygens?
My brain hurts just trying to pretend that I understand what he's talking about. But I sorta get it.... and that's okay
its high school physics ...
mr.mirror it’s university physics...this is literally at a MIT lol
@@mr.mirror1213 I took this in high school, yes, but theres nothing wrong with someone struggling to learn because it means they're interested and thats what matters in the long run
Sleep over that. Then look at it a second time. Maybe repeat. You will get it!
i m 14 yr old from India and i have studied these stuffs 2 months before covid-19 and i smiles when i saws these high lvl professors...... as a avg Indian kids has been studying these at the age of 14-16yr and if anyone is preparing for competitive exams as JEE in India...... i would probably says that he knows more than what been teached to him in his bachelor degree from MIT.............. for eg- Chirag falor knows everything that is been in his course ....BS program in physics at MIT😁😁 but there are pros and cons of each side, if anyone ask him how many practicals he had done in India,, probably he would not answer his/her question ........ 👍👍👍
This man is really teaching his lessons. In our university, professors just wants to solve a few questions and run away from class... thanks to internet and this kind of cool humans 😭😭
I am in 2nd year college pre-medical currently we are studying electrostatics in class which was kinda boring until i found your lectures your passion to teach physics is amazing the way you teach with complete dedication and love.Teacher's like you prove to student's like us physics is indeed beautiful thank you sir!.
:)
15:17 :O he didn't use the dotted lines trick, THE WORLD IS ENDING AAAAAHHH
my apologies
@@lecturesbywalterlewin.they9259 Can you make video on how you do that?
@@adokapo you can look it up on UA-cam there are many tutorials on how to do it. Its basically depending on the angle between the board and the chalk
I don't think it is possible to make a circle with that trick, the angle of the chalk with the board must remain constant.
@@defunct1373 I can make circles - angle between chalk and board does not change but *you move the chalk like a cone*
Respected sir, why are you touching that metal plate with your finger everytime before touching it to that sphere .....44:53 in lecture
en.wikipedia.org/wiki/Electrophorus
Before this lecture i could not believe that charge plate have constant intencity but now i it clears to me. Thank you sir
Sceintists are not born but Made during such lectures. Wish i had u as my teacher Sir Lewin. Never seen such a non-intuitive way of teaching.
Wooo , They have sliding boards amazing because we don't have any like that..
Edit guys - nice way too draw dotted lines .
Reference 44.46,when rubbing cat fur on glass plate it Gains - ve charge, keeping metal plate on glass plate result in induction - ve top surface, on touching the metal plate some electron flows into your body, make metal plate +ve charge, ON touching metal plate on sphere makes it also +ve charge, This continues
IF ABOVE EXPLANATION IS WRONG, CAN YOU PLEASE EXPLAIN HOW YOU CHARGED THE SPHERE
google electrophorus
Sir, really you are a great Teacher .
thank you Dr Lewin Walter hence you give me additonal knowledge from the high school one.