Four years ago my dad and I watched your lectures together. Today I'm near the end of my journey with physics (in academic terms). You do make us love physics!
Professor, I'm currently taking a class in electromagnetism and we're learning Maxwell's equations in multiple forms. In terms of E, in terms of D, etc. What would you say are the fundamental forms of Maxwell's equations to commit to memory? From which the other variations can be derived.
Sir, what happens if we only change the signs inside the cosine part of B and E and leave the outer signs intact? What difference does it create physically in the wave? I have seen the comments but my confusion is still there.
Since cos(-Q) is cosQ so no impact on wave but inner cos terms are phase terms so if u change those thing than wave can start from anywhere i.e. from origin from pie/4 or pie/2 or pue/8 this is the effect when we change terms inside cos otherwise wave property will still remain same but changing the value if u say like w inside cos than it is angular frequency so wavelengths can change but amplitude will still remain same
@@lecturesbywalterlewin.they9259 professor if E or B has a negative sign infront of it ; then there should be a phase difference of pi between E and B while the wave moving in -y . So shouldn't B and E be out of phase?
@@aritramondal4010 question unclear - you will have to refer to how many minutes into the lecture. *I can already assure you that what I did in the lecture is correct.*
10:15 ,why do we need to change the sign inside the cosine , isn't it that , just taking account of E * B would change the direction of propagation ??? i am confused please help
@@lecturesbywalterlewin.they9259 Sir we know that energy is a scaler quantity then why in the concept of poynting vector, energy is treated as a vector quantity
Lectures by Walter Lewin. They will make you ♥ Physics. Thankyou sir. During admissions at MIT its asked that "why you want to join MIT" So I want to ask you that why you joined MIT proff?
One 10 minute video was more valuable then 4 of my professors’ lectures.. thank you for the information
Lol happens to me too
Me too!
Four years ago my dad and I watched your lectures together. Today I'm near the end of my journey with physics (in academic terms). You do make us love physics!
Wonderful!
Excelente explicacion muchas gracias, saludos desde Argentina!
Thank you so much, Sir. It's very helpful! 😁
Most welcome!
Como siempre el maestro Lewin es un gran profesor de Physics.. Saludos de Perù
Thank you for the upload my good sir! :) Nice voice very entertaining
I like your bracelet and ring too
This is ASMR hell with the squeaking marker. Thumbs up!
Super Explaination..
Thank you 🙂
Very well explained.
Thanks Valter
Professor, I'm currently taking a class in electromagnetism and we're learning Maxwell's equations in multiple forms. In terms of E, in terms of D, etc. What would you say are the fundamental forms of Maxwell's equations to commit to memory? From which the other variations can be derived.
none of Maxwell's eqs can be derived from first principle. If you know 3 of them, the 4th eq can not be derived using those 3
Is there any light in that ring in your finger?
Yes, radioactivity!
Lectures by Walter Lewin. They will make you ♥ Physics. Isn't it harmfull to you?
Love from pakistan 🇵🇰
Sir I am confuses between curl and divergence of vector, plz sir tell the difference between both of this?
don't be lazy, use google; it's all there
😹👍
Sir i am stuggling to visualize Uniform Plane Wave. Would you consider to make a short video of it?
Thank you sir
Sir, what happens if we only change the signs inside the cosine part of B and E and leave the outer signs intact? What difference does it create physically in the wave? I have seen the comments but my confusion is still there.
Since cos(-Q) is cosQ so no impact on wave but inner cos terms are phase terms so if u change those thing than wave can start from anywhere i.e. from origin from pie/4 or pie/2 or pue/8 this is the effect when we change terms inside cos otherwise wave property will still remain same but changing the value if u say like w inside cos than it is angular frequency so wavelengths can change but amplitude will still remain same
@@mahigupta4120 wow thanks
Hold up. Can't E and B can have different phases if the material is not lossless, i.e. has conductivity?
To "Respected Professor Walter lewin" in case of propagation in -y if I put - in E or B equation; will they be in phase?
question unclear
@@lecturesbywalterlewin.they9259 professor if E or B has a negative sign infront of it ; then there should be a phase difference of pi between E and B while the wave moving in -y . So shouldn't B and E be out of phase?
@@aritramondal4010 question unclear - you will have to refer to how many minutes into the lecture. *I can already assure you that what I did in the lecture is correct.*
10:15 ,why do we need to change the sign inside the cosine , isn't it that , just taking account of E * B would change the direction of propagation ???
i am confused please help
direction of propagation (EXB) is reversed; listen closely to what I said.
@@lecturesbywalterlewin.they9259 Got it sir , thanks a lot for replying, it was a wonderful experience, getting a reply from you 😃
If Ex=0,Ey=0 and Ez=coskx coswt then what is magnetic field B
B field is zero as your E-field is not time dependent.
how could i ask questions from you professor?
ask here
Thanks professor for giving the privilege.
@@aritramondal4010 *ASK THE QUESTION*
@@lecturesbywalterlewin.they9259
Sir we know that energy is a scaler quantity then why in the concept of poynting vector, energy is treated as a vector quantity
@@anarkroy8637 bcoz the Poynting vector represents the *directional* energy flux
Where is 8.02x - Module 11?
biofiz82 We have down loaded all that was available. Apparently there was no Module 11
I was adamant the Professor was wrong with the necessary direction for E, in order to get the desired EM propagation, but I was using the wrong hand 😂
I feel something in my teeth
but some books says it E and H can be in leading of lagging in materials !
If E=Eo coskx coswtk̂ then how to find B
I cover this in my 8.03 lectures. Watch them!
Where can I get the questions you are discussing proffsr?
they are not available anymore. However, my videos almost always state the problem clearly enough that you would not need an additional text
Lectures by Walter Lewin. They will make you ♥ Physics. Thankyou sir.
During admissions at MIT its asked that "why you want to join MIT"
So I want to ask you that why you joined MIT proff?
I was invited by MIT to spend there a 2 year postdoc. After 6 months I was promoted to Professor and I never left.
Are there Indian students at The MIT
yes, use google
Thank you for not deriving anything 🙃
Imagine those screeching sounds coming as he drags your fingernails across his board.
thank me later 😬
Rex Galilae 🤣😂😂😂
I'm gonna down vote this bedevilry 😈😈