8.02x - Lect 26 Traveling Waves, Standing Waves, Musical Instruments
Вставка
- Опубліковано 25 сер 2024
- Traveling Waves, Standing Waves, Resonances, String Instruments, Wind Instruments, Musical Instruments
Lecture Notes, Oscillating Sound Cavities - Fundamentals of Wind Instruments: freepdfhosting....
Assignments Lecture 26, 27 and 28: freepdfhosting....
Solutions Lecture 26, 27 and 28: freepdfhosting....
This is the most beautiful presentation ever. For the first time I realize that a standing wave is nothing more than a cosine modulating the amplitude of a sine wave. Amazing. I love you!
:)
@Za Yn you should mention india not kashmir we need to represent our country not unionterritory
@@sudhamshreddy2756 I guess he has deleted his comment
@@sudhamshreddy2756 bro why are you Indians so wierd. Always saying love from India. It’s not that deep
@@lukaide6359 love you from india🇮🇳🇮🇳🇮🇳
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. Thanks
❤❤❤❤
26:27
Then it gets to the brains, if there are any.
🤣🤣🤣🤣
Lectures by Walter Lewin. They will make you ♥ Physics. Thanks
You actually made me fall in love with Physics. You are the Legend, Sir!
Sir you explained standing waves to me! My physics teacher had confused me. Thank you so much!! You are the best physics teacher I will ever see. I KNOW IT
😊
The simple mention of the fact that, in the standing wave equation, the spatial and temporal information is not interlinked makes for a great tool for understanding how standing waves aren't being shifted left or right (speaking purely in terms of vertical vs. horizontal displacement).
Excellent explanation of the standing wave professor. Thank you!
I will never forget you Professor Walter Lewin. You are the only physicist that taught Physics with great care and thoroughness in terms concept. Your demonstration proves extremely valuable that registers in my mind. I thank God for your life, and contribution to teaching physics in a way that makes me appreciate and love Physics. You enlightened me of all the topics that I didn’t really understand the concept well, or sometimes not at all because of lack of faculty by others. You are such a gift in the world of Physics. Thank you Professor 🙏.
I honestly have reconsider many times going on in my University in Italy since I had no problem in mathematics but Physics was making me bored, at a point that I was going to Economics and Politics because it were more real to me.
Thanks is not enough professor, if you'll come back to Europe one day and make a trip in Venice, I'll be the one unveloping the red carpet all over Venice.
My next-to-be AeroSpace Engineering Degree is largely becaming a dream come true thanks to you Professor, you made me interested again in Physics and the applications it has.
Dr. Lewin, I've watched several of your lectures since the start of my first year in my physics major and I just wanted to take the time today to thank you for all your dedication you put into these lectures. Thank you for your amazing teaching and making me love physics.
+Enrique Morell Thanks Enrique for your kind words.
"Sound" sounds very very interesting because of YOU, Sir.......
:)
This is the first Walter Lewin lecture I have ever seen and this is the best lecture I came across in my entire life. Now I know why you are famous :D
Cheers from India! ❤❤❤
:)
I usually find animation more helpful to understand. But animation are nothing compared to these practical examples. You are a legend :).
Great teaching!. This is the way in which Physics/Math should be taught.
You are an incredible teacher and a wonderful human being. You involved your students in the lecture and gave them a chance to demonstrate their talents to everyone. Very rarely is this the case - most teachers are content showing off their own talents (if even that). I will remember this lesson - to give others the chance to impress me - because you never know what amazing talents people have hidden.
well the last 2 min were really appreciable,he can do anything for physics awesome professor👍👍👍👍
sir,i'm a student of class 11. I regularly follow your lecture and your teaching come alive to me. I love u sir as well as Physics. Huge respect and love from BANGLADESH.
Blessed to witness these lectures, sir! It gives me eternal happiness
After i watched this lecture i downloaded a software oscilloscope(for microphone) and a frequency generator and i am testing various frequency's and harmonics to find nodes and i am sliding with my chair slowly away from the speakers to find nodes ..its really fun when i find a node i feel a drop in pressure..its been 2 hours i have been doing this LOL and not bored at all! thankyou prof. lewin
could you please share the source to download the software? I would really appreciate it. I too am interested in trying it on my piano and having some fun
Thnx a lot :)
Many Thank You for the Great job you have done! Probably the only clear explanation (at least for me) of the standing waves that I have come across. Bless you!
You're very welcome!
✨learning, performing, playing & even listening to music over1/2 my life & I now know I never really understood music ! Actually I may/ will need watch this again & possibly again😬🤫😁
Thank you Sir! ✨
This was like rediscovering musical instruments. Thank you so much.
It’s been years since ny last Physics class. This vid reminded me how much I love this stuff! Thanks!
You're very welcome!
really amazing lecture.
I didn't understood these when my physics teacher thought us this . He just wrote bunch of equations that and no one listen to him .
Now i am foing all these again and hopeful to find your lecture ( I am preparing for jee so i am reading all thses)
Excellent
So far I was wondering how the standing wave phenomenon possible. My mind was a mess. Now it's cristal clear how this bizarre thing happens. Thank you so much professor. I love you so much ♥️♥️♥️
The best demonstration sir. So glad, that me could travel back in time to see your lectures sitting in my home from India
❤
I like the way you tie the mathematics to physical demonstrations. It is all to easy to to get lost in mathematics and lose sight of the physics.
For the first time I have understood x-vt concept. Thanks a ton great sir... love you.
his lectures always recover my passion for physics again after weeks of unintuitive lessons from my physics class
Thanks Professor Lewin you make your lectures very interesting. Thus makes us love physics.
I love you sir. May you never stop teaching.
Beautiful, simple and very instructive Demonstration of standing wave with that rope.
Thank You Professor... These lectures are amazing
This teacher can inspire anyone to learn physics. I myself am inspired by him. This is my channel about Science.
beautifully orchestrated by the great Professor Lewin!
Thanks for listening
I love you man. you are the teacher who have understood the depth of conceptions. i really learn from your videos and i appreciate you😍😍😍
thanks for your kind words
Anyone else notice that he played Epona's song from The Legend of Zelda Ocarina of Time at 33:50?
you think he did that on purpose? XD
Probably accidental. I could be wrong though!
Sir, you are more than amazing.your presentation made me love physics.❤️❤️❤️❤️❤️❤️❤️
Glad to hear that
@@lecturesbywalterlewin.they9259 feeling so amazing that a great person chatted with me .🥳🥳
Thank you professor.
Violinist at 43:35 played Ysaye's 3rd sonata.
Wow! With this teacher everyone would want to be a physicist!
I am so enlightened to watch this lecture video of the Doctor, Walter Lewin.
Nothing can be better than this
Wow! Very wonderful playing of ysaye’s third sonata by the student.
Superb dedication Professor. Love from India ❤
After filling lakhs of fees, real knowledge is found on UA-cam for free.❤️
Thank you for these amazing classes ❣️😊❣️
You're so welcome!
I feel like studying physics .
The most beautiful video❤️
Very good lecture Sir. Thanks and Regards 🙏🙏🙏🙏🙏
Most welcome
Awesome lecture!!!
Glad you liked it!
Woww.
Professor Walter Lewin changed his voice more sweeter than my Girlfriend..❣️
Beautiful sin function you drew. Those aren't easy to draw.
Thanks for the practical explanation! My teacher didn't explain me exactly what it's physical meaning is...
You are true inspiration..what a extremely well thought lecture...genius,,omg
Wow, thank you
Watch this Lecture and listen to Kind of Blue. Preferably at the same time.
Thank you, professor!
You are welcome!
This lecture is absolutely beautiful.
Thank you sir.
Best sir. this kind of visitation not seen and"herd,😀" before I would really really really really like to learn from you
35:03 third harmonic actually because the interval with the next one is a fourth. And 35:18 is the second harmonic because the interval with the harmonic above it is a fifth.
Enjoyed a lot this lecture while learning!❤️
i am a bangladeshi student and i nevet learn it like this thank you so much sir btw i am a physics lover too
:)
Hello, Professor Lewin. My textbook used cosine to represent standing wave instead of sine. So, y1 + y2 = 2ysin(kx)sin(wt). I felt confused. Are they the same? Can you explain it to me?
+JunYu Lei If the string is closed at both sides, then at x=0 and at x=L the displacement must always be zero. As long as your solution meets those conditions it does not matter whether you have sin or cos.
If the string is closed at one end but open at x=L, then your solution should give a displacement of 0 at x=0 at all times and dy/dx must be zero at all times. As long as your solution meets those conditions it does not matter whether you have sin or cos.
I love you, sir. You've been my whole world since 11th grade. You really made me love physics. Please don't die before I come to America ;) . I really wanna meet you.
wtf Fabian!! Why the hell are you in a physics class and not smokin in a jazz band??
Wow I had a doubt about harmonics and standing waves I came here and it got resolved thanks!!
super!!!
@@lecturesbywalterlewin.they9259 oh my god you replied so quick!! I love you Walter lewin sir!! Only if I could meet you and talk to you!!!
44:10 and I am clapping sitting in front of my screen.
I'm there clapping at 13:00 . Finally understand what a standing wave is
Came here to learn actual meaning phase. Thanks sir walter
umm in the beginning,, so 18 is the omega.. but isn't omega suppose to have pi or at least a degree symbol in it..?? I don't get why the omega can be just an integer without any degree symbol..
+GThinks the unit of omega is radians per sec. thus 1/sec.
8.03 seems as exciting
:)
I wish my teachers were that good.
Had to tune the violin everyday in wisconsin!
Is this a university course? My school taught us at 11grade
This is so beautiful. God damnit. Why are you so marvellous! Unbelievable. My hero forever !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1
:)
31:37 that’s some useful information even outside of music and physics ;)
In reed based woodwinds instruments, e.g. clarinet or saxophone, if one blowconstantly on a note, theb open the register hole which eliminate the fubdamental freq so you get a note in hugher octave but then you close the hole and magically you do not get the low fundamental as long as you continue blowing air in. Only when one stops and dtart again the low fundamental freq appears again. I wonder why?
You are definitely a GENIUS
:)
6:00 sir how is wave exactly as 2sin3(x-6t) getting produced even if the source is also moving horizontally?
Best presentation professor
Glad you think so!
You pick a 4 unique music instruments based by its special point. I interest in the swinging string and the instrument that produce low-tone sound as it is work like ancient music instrument, we use string pundulum and metal another one sound like some kind of shell (hard to find for a perfect voice).
51:18
Haha
So that's how they produce such sounds in Television Cartoons...
Amazing teaching style
Beautiful!
perfect lecture
Love you sir .... ☺️
Thank you Proff. Lewin for this lecture, now I can give my exams without any fear:-)
:)
Wonderful- a treasure.
35:27 how did u estimate the numerical values of frequency in Hz sir? Absolutely mindblowing
Sir here why you take moving graph firstly and how you thought that for positive x direction we should take minus t and vice-versa?....
sir, in sin(kx-ωt) , if i substitute x=vt , where is the linear velocity of the wave and you said v=ω/k. Then k gets cancelled and i get the remaining ωt. So then ωt - ωt becomes zero. I know this is not correct but pls tell me where am i making mistake. waiting sir..............
kx measures the number of radians travelled by a point on the wave to get to a particular x value.
wt measures the number of radians travelled by a point on the wave to get to a particular t value.
x and t are independent dimensions.
By linking them you're tracking a single point not an infinite sine wave.
So kx - wt becomes "take the number of radians it took to get to this place in space minus the number of radians it took to get to this place in time" which are obviously always the same.
Sound was very boring for me but because of you it is interesting
Really your lectures make love physics
may I ask what piece of music was tom playing on his violin? at 43:31 it sounds beautiful.
Ysaye violin sonata, I'm almost sure that it is n°3
nice, thank you very much! :)
33:48 why does the flute have a whistle type opening at beginning and not just a hole?
26:27 Thug life professor WALTER LEWIN 😎😎
In case of fundamental frequency, we always get high amplitude as compared to other harmonics so is it safe to say that if we want to have destructive resonance then fundamental frequency is the most suitable option for it?
This will often be true. However, it's in principle possible for objects to break much easier in the second harmonic than in the fundamental. Suppose you took a glass rod of length L which is thinner (thus weaker) near L/4 and 3L/4.. It may then be easier to break it when you excite it in first harmonic above the fundamental than in the fundamental. There may be many objects (including bridges and glass wear) that are more vulnerable at res freq above the fundamental than at the fundamental.
Love you sir This made my day 😍😍
Amazing lecture
Thanks a lot!
i did not understand how the wave was created by a rotating wheel. Won't the string just twine to the wheel?
absolutely wonderful
34:28 plays trombone with false notes 😂
I have a question about the traveling wave equation y=2sin3(x-6t). When I search on the internet I always find that the equatin is y=2sin(wt-kx). When we write equation for AC voltage it's also u(t)=U*sin(wt + "theta" ). So I'm not sure which one is correct. Please forgive me if I am missing something obvious, thank you in advance.
+Nikola Vulinovic TRAVELING WAVES
y=2sin3(x-6t) = 2sin(3x-18t). Thus k = 3 (lambda = 2.1m) and omega is 18 rad/sec. y=2sin(wt-kx) => y=-2sin(18t-3x). Again lambda = 2.1 m and omega = 18 rad/sec. The - sign is a phase change of 180 degrees. NO PROBLEM! These are TRAVELING WAVES!
+Lectures by Walter Lewin. They will make you ♥ Physics.
u(t)=U*sin(wt + "theta" This is not a traveling wave.
+Lectures by Walter Lewin. They will make you ♥ Physics. Thank you so much for clearing that up for me and answering so quickly. I see now that I need to study a bit more before asking a question. I would just like to take the opportunity to say that I love your lectures they're so interesting and helpful, Thank you again very much.
Great Lecture Professor!
+Fabrizio Tabasso Thank you!
Sir, I have a question about standing wave, if wave (when it reflects from the wall) changes its phase for 180 degrees shouldnt then the reflected and the coming wave be out of phase and cancel each other
watch my 8.01 and 8.03 lectures on standing waves.
cancellation ONLY accurs at the nodes of the standing waves.
This will help to clear iit jee🙏🙏🙏
Exactly how physics should be presented