Sir, the demonstration at the end of this lecture is ,by far, the best. Hats off to you for such dedicated service towards teaching. Teachers like you are indeed, rare. I feel privileged that technology has allowed me to witness these beautiful lectures miles away from the classroom even after so many years.
@@PrinceKumar-hh6yn well actually then the velocity of the ball would be really really small. But due to the gigantic mass of that pendulum it'll still hurt a lot
No actually the air drag is there so there is a resistive force acting and thus there is a loss of energy so there would ve been no way that it would go past the initial postion
Hey professor, I wanted to say thank you for the way you teach physics. I'm not a physics student but recently I've been watching your lectures and the way I look at the world is not the same anymore and it's amazing. Now I love physics.
really impressed by your lectures ! i have gone through your every video lectures ! this has really helped me get clear concept and has increased my craziness in physics !
This lecture changed my life by making me want to become an engineer. It was last year when I was sad with my incompetence with physics so I thought I would relearn the concepts in terms of mathematics and calculus which they did not teach in high-school. I started off with work and energy. All my misconceptions were eliminated by watching this video in the summer and I ended up loving to derive everything from scratch. I thought I'd share my experience so I created a TH-cam video about how my physics teacher's notes were incorrect, and my classmates got him to project the video to the class! I had this amazing story to talk about in my university interviews and I ended up being admitted to the #1 university in Canada for Engineering thanks to it. You have my everlasting gratitude Professor Lewin.
Hello Professor! I enrolled in college at the age of 29: I work durying the day and study the evening. I procrastinated physics as much as I could, since I was always so scared of it, to the point that I almost did not enroll because of it. Now that I have to study it, I'm so glad that I found your lectures on youtube. Everythingy you explain is crystalline (well maybe not always at first, but after some reasoning it's absolutely obvious), and you're actually making me LOVE physics. Your demonstrations are so clear that I repeat your demonstrations every day so that I may fix them in my head forever (I hope!). I was puzzled when I saw that your videos had almost no comments: however I just found out that it was an entire set of videos uploaded from another user, with very low quality and with very few views. Sorry if I wrote so much, but I just wanted to express my gratitude. I'm quite sure that when I'll get to Electromagnetism I'll be finally able to get it (I had to study it for another exam, but I couldn't really grasp the concepts). In short: thank you so much for your exceptional work and passion, and a big hello from Italy!
Thanks for your kind words. My TH-cam channel has 118,000 subscribers! This channel alone has about 20k viewers every day. There is another channel with my lectures but the video resolutions is not as good as on mine.
Exactly! And I've been following your lectures on THAT channel! And that is why I was so puzzled. When I found out your REAL channel today, I had a huge smile on my face, and I wanted to finally thank you for your job! So Thank you again, and have a wonderful day professor! :)
as a 14 year old who has yet to touch calculus, the maths is a bit wonky but I seem to have grasped the basic concepts. Thank you for the strangely entertaining lecture, prof Lewin
Me too! I am also 14 y/o and have learnt by far , most of calculas, both differential and integral calculus from Internet. This is quite a fascinating topic that has helped me to grasp Sir Lewin's lectures. Thank God I learnt that before.
when I habituated to watch your lectures I thoroughly enjoying the lectures. I will not have any pen and paper while listening to your lecture.You are one of greatst teachers I have ever seen
Oh!! Professor!! You're the majestic person to determine, your life to make physics more engaging. These lectures were provided before my birth. And till the huge improvement of the learning system still, your lectures makes me fascinated every time :3
@@lecturesbywalterlewin.they9259 why cant the bob keep oscillating forever at the same height. Why does it lose energy is it air resistance? by the way big fan
I tell you professor, My teacher punished me and asked me to explain this in front of whole class! Students understood better than they usually when my teacher explains, and he was like “Woah” ! Thank You very much Sir! Love from India 🇮🇳
This is just beautiful. For 49 minutes, the lecture hall was just like an art exhibition. I can't find words to explain how MUCH these lectures have changed my perception of Physics .It really is a dance of equations isn't it? :) I love you Walter Lewin ❤
Waw!!!...! I'm a student from Brazil and what I have to say is simply that your classes are incredible Mr. Lewin, you're a historical man, your work providing free, democratic and global high-quality education in physics will change humanity forever...
Laws of conservation of energy show a lot of elegance and beauty of physics. Thank you for sharing it with the help of such beautiful and brave demonstrations!
37:00 this actually blew my mind off. Now I know how physicists, astronomers and scientists calculate the gravitational pull on one heavenly body. So refreshing and also cool to know that. Thank you Professor Lewin!
Sir I am from India and am a big fan of your teaching style..I am currently preparing for JEE which I will give after 3 years..your lectures are helping me a lot to understand the concepts in depth. Thank You Sir.😊
You are really a life changing person and experience for a student professor. Watching someone teaching for the love of physics in today's world, as of being a student aspiring reasearch, i feel highly privileged and extremely fortunate from the walls of my house to be honoured to study from your lectures, it really makes me feel that my aspirations could come true and soon u will be meeting a young scientist colleague added to your memories!😊❤ Love and high respect from india
Sir, thank you for responding to the comments as you do. For many of us students with similar difficulties and questions, your answers are extremely wonderful and helpful.
Thank you very much, Professor Lewin. I have been using these lectures to supplement my online Mechanics class, which has no lecture. I'm very grateful.
Thank you for uploading these lectures. I'm a physics student myself currently struggling in my first year (various reasons) and these videos really help keep myself in check. Excellent quality.
A small boy from a small village in India saw a video on physics by a great teacher Walter Lewin (This has happened 7 years back).. That video inspired him like anything and made him to take masters degree in physics and teach physics.
Derivation of the kinematic and force/work/energy equations using calculus is awesome isn't it? You do some (completely legitimate) algebraic magic and these wonderful and profound relationships just seem to fall out as an after-thought! I would have loved to have been there when Messrs Newton, Huygens, Laplace et al were doing this for the first time...
I am a masters student in engineering, yet I enjoy binge watching your lectures like a kid who is being introduced to physics the first time. Love you Professor Lewin!
Just want to say thanks recently completed a degree in physics and will be going further to get that phd .I watched all your lectures series as I was learning high school and first year university physics and still come back from time to time to watch all the classic experiments and discussions thank you very much for these lectures .
I'm in final year of Mechanical Engineering but I'm still studying your lectures on Physics. This intuitive and simple approach has gripped my mind to your lessons. Thank you so much for sharing these. :)
Arriving in class 11 I just started hating physics,but after arriving to your channel I started loving physics again.❤️❤️ Thanku sir(ur student from India)
I remember that my 8th grade science teacher always said that doing something faster won't change the amount of work that you do. Would I be write if I said that he is wrong for the reason of your acceleration would change therefore the force would change and then the work output would change. Also they way he taught us work (hopefully for obvious reasons) was a lot more simple along the lines of pushing an object (the force) some distance. Where you came at it at a whole different standpoint, do you say that he did something wrong with explaining it?
If you lift a mass m from A to B with vertical distance h and you do this with ZERO speed in A and ZERO speed in B, then the work you do is mgh, it's the same no matter how fast you do it.
Very Famous lecture of Sir Walter Lewin....Now I got to know why it's famous.... PHYSICS WORKS! AND I AM STILL ALIVE!!!! This gives me Goosebumps sir....Loads of Love
Professor, can you please tell me where can i find assignments given by you based on these lectures. (your lectures are just amazing. I have never seen such an enthusiastic PHYSICS professor like you so far in my life )
Professor i have a request if you can give these lectures in hd quality i will be more happy. and I wanted to say thank you for the way you teach physics. I'm not a physics student but recently I've been watching your lectures and the way I look at the world is not the same anymore and it's amazing. Now I love physics.
My vintage MIT course lectures are from 1999, 2002 & 2004. This was at a time that there were NO online courses yet. My 8.01 lectures were on MIT TV already in 1999 and my 8.02 lectures in 2002. These lectures were among the very first on MIT's OCW. Ofcoz, our equipment was very primitive compared to 2018. But the power of these lectures has not changed. The power is not in the resolution.
Hi professor. Many thanks for your videos. I wanted to ask you (minute 40:45 ) why the sign of the "dr" within the integral is not negative, since the force is in the opposite direction ( the force is to go from R to Infinity according to your drawing and the movement is to go from infinity to R) Thank you very much in advance and for all your lessons, they are really useful !
Professor Lewin, I have 2 questions: 1) Am I correct in thinking that Conservation of Mechanical Energy would not work if we chose to invert the y axis (e.g.: as y decreases, the value for U increases)? And 2) Why does Conservation of Mechanical Energy apply when gravity is not the only force acting on the object (such as with the pendulum where there is a tension also acting on the weight)? I cannot thank you enough for your part in making this top level education available to everyone and for taking the time to answer our questions.
+Matthew Davy (1) The conservation of mechanical energy is independent of your coordinate system. (2) The conservation of mechanical energy is best expressed in the Work Energy Theorem. The work done by ALL forces that act on a mass m in going from A to B is KE_B - KE_A. In the case of a pendulum the tension does NO work as the tension (force) is always perpendicular to the displacement of the bob. In the case of a freely moving pendulum (ignoring air drag and possible friction), only gravity is doing work. If the bob changes its vertical position by an amount h, then the work done by gravity is mgh. This can be positive or negative depending on the sign of h.
+Lectures by Walter Lewin. They will make you ♥ Physics. After some honing of my intuitions and ensuring my signs are all correct, I think I am understanding the first point. And thank you for the clarification on the second. Have a great day!
@@lecturesbywalterlewin.they9259 Lol, well I didn't mean that it is literally me, I meant that it is the same expression on my face when I am in physics because I have found it very hard to understand :) You are a great professor by the way.
Respected sir . Don't Mind Sir I am from India.I am in class 11 Sir this level of physics you are teaching in college but sir in India this level of physics have been taught to class 11 students . So you should teach more high level of physics ????????????😊
h=2.5r for the roller coaster works only in the case of sliding motion, the rolling of the ball takes up part of the initial potential energy and thereby reduces the kinetic energy at the point D for looping the loop
The last example of P.E and K.E in this lecture was the example which changed my life totally, Because i saw Pr. Walter Lewin First time in my life on phone while he was demonstrating this phenomenon really Since then my understanding towards world is totally changed 😊. Love you Professor ❤️
Thank you so much sir for uploading such an amazing lecture. Besides being interesting it made all the concepts very clear and it was really helpful in preparation. 😊
Professor Lewin, did physics come easily to you, or did you struggle when first acquainting yourself with the subject? I love math a lot, and I love physics; I am majoring in math and physics. I am having a difficult time "thinking like a physicist." Was there a time when you were first learning physics that the subject was difficult for you?
You could make a fun problem out of analyzing the motion of a helicopter during an autorotation. The v-square term really helps in determining where the helicopter ends up.
Sir loved your lecture. This concept helped in clearing jee advanced, India's most prestigious high school exam . I wish I will meet you when I will come in MIT for masters. Thank you once again Love from India
Why at 46:35 the glass was broke? He was also released that bob with 0 speed from that point? Sorry he was actually giving a little pit push which of the cause of breaking the glass.
Een klassiek vakman zonder tierelantijnen en precies de docent zoals die moet zijn, duidelijk en gedoceerd, afgerond met een aansprekende demonstratie. Bijzonderder hoeft het niet te zijn.
@@lecturesbywalterlewin.they9259 U wilt zeggen, dus best wel bijzonder,.. Wat mij opvalt aan uw colleges is dat de studenten geen vragen stellen of komen met opmerkingen, is dat vanwege de videoopname? Ik was altijd nogal een vragensteller, vandaar
In reference to the experiment starting at 48:00, is another reason why you didn't get hit by the ball because energy cannot be created only converted? So eventually, if you left the ball swinging, it would stop? A bit like perpetual energy? I'm really enjoying your physics lectures, and have been watching them in my spare time. I am planning on rewatching, and taking notes, so I can understand more.
Never thought my fear of physics will be converted to love for physics with just one video ! Teachers who makes physics boring are real criminal ! Thank you sir for making me fall for physics !
Sir,In example at 5:43 ,the given condition is that Velocity at A=0=Velocity at B,so how does that object can move that height h with zero net force(as Force by F and force by gravity gives zero net force) Please explain it sir Sir,also what does it actually mean when in physics it is said that "an object is displaced "slowly" by some force F"(For example it is used in the definition of electrostatic potential )
![🔴 ฟุตบอลแชมป์กีฬา 7HD แชมเปียน คัพ 2024 [รอบรองชนะเลิศ]](http://i.ytimg.com/vi/zPm8ClLVhoE/mqdefault.jpg)
![🔴 ฟุตบอลแชมป์กีฬา 7HD แชมเปียน คัพ 2024 [รอบรองชนะเลิศ]](/img/tr.png)
Sir, the demonstration at the end of this lecture is ,by far, the best. Hats off to you for such dedicated service towards teaching. Teachers like you are indeed, rare.
I feel privileged that technology has allowed me to witness these beautiful lectures miles away from the classroom even after so many years.
:)
@@lecturesbywalterlewin.they9259😊
"Physics works, and I'm still alive."
I was really scared to imagine if the ball had come closure just a slightest even..!🙄😴
👍
@@PrinceKumar-hh6yn then u don't trust physics
@@PrinceKumar-hh6yn well actually then the velocity of the ball would be really really small. But due to the gigantic mass of that pendulum it'll still hurt a lot
No actually the air drag is there so there is a resistive force acting and thus there is a loss of energy so there would ve been no way that it would go past the initial postion
Hey professor, I wanted to say thank you for the way you teach physics. I'm not a physics student but recently I've been watching your lectures and the way I look at the world is not the same anymore and it's amazing. Now I love physics.
+manuel di nucci Thank you! Keep it up!
From egypt big greating❤
Watching you talking about physics is like listening to mozart.... thank you for your magic.
:)
Dude, I love this guy...he even risks his life to make the concepts clear to his students..one of the best physics professors out there
Love from india! Big fan of your teaching professor lewin.
Great, thank you
@@lecturesbywalterlewin.they9259 Sir ,I want to know that how you create dotted lines so faster.
@@satyamthakur11a28 practice and experience
@@satyamthakur11a28 jee aspirant?
@@satyamthakur11a28 By holding the chalk perpendicular to the board, not at an angle.
you know he's THE ideal teacher when he puts his life on the line. Hats off professor!
really impressed by your lectures ! i have gone through your every video lectures ! this has really helped me get clear concept and has increased my craziness in physics !
:)
Best professor I have every seen! thank you very much for allowing us to watch such a informative, dramatic and vivid lecture!
Thank you Mini for your kind words.
This lecture changed my life by making me want to become an engineer. It was last year when I was sad with my incompetence with physics so I thought I would relearn the concepts in terms of mathematics and calculus which they did not teach in high-school. I started off with work and energy. All my misconceptions were eliminated by watching this video in the summer and I ended up loving to derive everything from scratch. I thought I'd share my experience so I created a TH-cam video about how my physics teacher's notes were incorrect, and my classmates got him to project the video to the class! I had this amazing story to talk about in my university interviews and I ended up being admitted to the #1 university in Canada for Engineering thanks to it. You have my everlasting gratitude Professor Lewin.
I moved to medical studies, and I am still feeling excited when I watch your lectures.
Great Professor. (from Morocco); much Love:)
Hello Professor! I enrolled in college at the age of 29: I work durying the day and study the evening. I procrastinated physics as much as I could, since I was always so scared of it, to the point that I almost did not enroll because of it. Now that I have to study it, I'm so glad that I found your lectures on youtube. Everythingy you explain is crystalline (well maybe not always at first, but after some reasoning it's absolutely obvious), and you're actually making me LOVE physics. Your demonstrations are so clear that I repeat your demonstrations every day so that I may fix them in my head forever (I hope!).
I was puzzled when I saw that your videos had almost no comments: however I just found out that it was an entire set of videos uploaded from another user, with very low quality and with very few views.
Sorry if I wrote so much, but I just wanted to express my gratitude. I'm quite sure that when I'll get to Electromagnetism I'll be finally able to get it (I had to study it for another exam, but I couldn't really grasp the concepts).
In short: thank you so much for your exceptional work and passion, and a big hello from Italy!
Thanks for your kind words.
My TH-cam channel has 118,000 subscribers!
This channel alone has about 20k viewers every day.
There is another channel with my lectures but the video resolutions is not as good as on mine.
Exactly! And I've been following your lectures on THAT channel! And that is why I was so puzzled. When I found out your REAL channel today, I had a huge smile on my face, and I wanted to finally thank you for your job! So Thank you again, and have a wonderful day professor! :)
:)
as a 14 year old who has yet to touch calculus, the maths is a bit wonky but I seem to have grasped the basic concepts. Thank you for the strangely entertaining lecture, prof Lewin
i wonder how far you’ve come by now
Me too! I am also 14 y/o and have learnt by far , most of calculas, both differential and integral calculus from Internet. This is quite a fascinating topic that has helped me to grasp Sir Lewin's lectures. Thank God I learnt that before.
Sir Even You Don't how much it is helping Students / aspirants of NEET and JEE.........Love you Physics God
24:35 I love when he draws dotted líne and the sound even
when I habituated to watch your lectures I thoroughly enjoying the lectures. I will not have any pen and paper while listening to your lecture.You are one of greatst teachers I have ever seen
Sir Walter when are they conferring a Nobel prize for a lifetime dedicated to lectures and making us all love physics? If not given already
Oh!! Professor!! You're the majestic person to determine, your life to make physics more engaging. These lectures were provided before my birth. And till the huge improvement of the learning system still, your lectures makes me fascinated every time :3
Wow, thank you!
@@lecturesbywalterlewin.they9259 why cant the bob keep oscillating forever at the same height. Why does it lose energy
is it air resistance? by the way big fan
I tell you professor, My teacher punished me and asked me to explain this in front of whole class! Students understood better than they usually when my teacher explains, and he was like “Woah” ! Thank You very much Sir! Love from India 🇮🇳
The Greatness of this Professor is huge.
This is just beautiful. For 49 minutes, the lecture hall was just like an art exhibition. I can't find words to explain how MUCH these lectures have changed my perception of Physics .It really is a dance of equations isn't it? :) I love you Walter Lewin ❤
Waw!!!...! I'm a student from Brazil and what I have to say is simply that your classes are incredible Mr. Lewin, you're a historical man, your work providing free, democratic and global high-quality education in physics will change humanity forever...
thanks for your kind words
Laws of conservation of energy show a lot of elegance and beauty of physics. Thank you for sharing it with the help of such beautiful and brave demonstrations!
Glad you enjoyed it!
37:00 this actually blew my mind off. Now I know how physicists, astronomers and scientists calculate the gravitational pull on one heavenly body. So refreshing and also cool to know that. Thank you Professor Lewin!
:)
Sir I am from India and am a big fan of your teaching style..I am currently preparing for JEE which I will give after 3 years..your lectures are helping me a lot to understand the concepts in depth. Thank You Sir.😊
Did you clear JEE or not? If so, which college and branch?
@@mannmehta24yeah i also want to ask 😂😂
You are really a life changing person and experience for a student professor.
Watching someone teaching for the love of physics in today's world, as of being a student aspiring reasearch, i feel highly privileged and extremely fortunate from the walls of my house to be honoured to study from your lectures, it really makes me feel that my aspirations could come true and soon u will be meeting a young scientist colleague added to your memories!😊❤
Love and high respect from india
love the phrase "Physics work"
I admire so much about his lecturing. possibly the top is a fantastic use of the blackboard. definitely a lost art nowadays.
Sir, thank you for responding to the comments as you do. For many of us students with similar difficulties and questions, your answers are extremely wonderful and helpful.
The most knowledgeable and best 49 minutes in my life
34:18 Gravity Sucks, bro!
yes it does
I thought I was the only one who laughed at that 😂
Thank you very much, Professor Lewin. I have been using these lectures to supplement my online Mechanics class, which has no lecture. I'm very grateful.
:)
Big fan from Brazil professor Lewin.💙👍
sir I am a jee aspirant i have joined a good coaching but your explanations helps the most. you are the best physics teacher
I wish i could meet this man once....love from INDIA...!
Thank you for uploading these lectures. I'm a physics student myself currently struggling in my first year (various reasons) and these videos really help keep myself in check. Excellent quality.
That was a phenomenal lecture. Thank you Professor Lewin for teaching physics to the world.
All of you are in for one best teacher, I am from India 🇮🇳🇮🇳🇮🇳🇮🇳🇮🇳.
'Physics works, and I'm still alive'
Satisfaction line.
I haven't seen someone teaching physics in such an amazing way, u r amazing completely amazing
Full Chapter WEP of IIT JEE in one lecture ❤️❤️🔥🔥
Hello
I want to talk with you. Please response.
A small boy from a small village in India saw a video on physics by a great teacher Walter Lewin (This has happened 7 years back).. That video inspired him like anything and made him to take masters degree in physics and teach physics.
Sir I am from India..I am a student of class 11 and I just wanted to say these lectures help a lot
Physics is the poem of logic that you are showing me with rhythm. Love from Bangladesh 🇧🇩🇧🇩🇧🇩..... A big fan of you'r.
2:51 this guy is like "wtf did i just saw"
Wacthing your lectures is like wacthing the beauty of physics . like richard .p.feynman 's convesation
:)
Derivation of the kinematic and force/work/energy equations using calculus is awesome isn't it? You do some (completely legitimate) algebraic magic and these wonderful and profound relationships just seem to fall out as an after-thought!
I would have loved to have been there when Messrs Newton, Huygens, Laplace et al were doing this for the first time...
Fantastic & Phenomanal.
So real and understandable.
Your students are very lucky.
Many thanks for sharing with us.
It's my pleasure
I am a masters student in engineering, yet I enjoy binge watching your lectures like a kid who is being introduced to physics the first time. Love you Professor Lewin!
Just want to say thanks recently completed a degree in physics and will be going further to get that phd .I watched all your lectures series as I was learning high school and first year university physics and still come back from time to time to watch all the classic experiments and discussions thank you very much for these lectures .
+matt champion Matt, you are very welcome!
if only i had had them back in the 90s...
Well explained about work energy theorem Thanks a lot sir
Love from India 🚩🚩
My pleasure
Big fan sir first time see your video and now i am your fan . Love From India ...
That was the coolest lecture professor.
I'm in final year of Mechanical Engineering but I'm still studying your lectures on Physics. This intuitive and simple approach has gripped my mind to your lessons. Thank you so much for sharing these. :)
:)
Teacher you are really amazing. Wounderful💯. I really love that lectures.God bless you😇.
Arriving in class 11 I just started hating physics,but after arriving to your channel I started loving physics again.❤️❤️
Thanku sir(ur student from India)
I remember that my 8th grade science teacher always said that doing something faster won't change the amount of work that you do. Would I be write if I said that he is wrong for the reason of your acceleration would change therefore the force would change and then the work output would change.
Also they way he taught us work (hopefully for obvious reasons) was a lot more simple along the lines of pushing an object (the force) some distance. Where you came at it at a whole different standpoint, do you say that he did something wrong with explaining it?
If you lift a mass m from A to B with vertical distance h and you do this with
ZERO speed in A and ZERO speed in B, then the work you do is mgh, it's the same no matter how fast you do it.
Essential video for Jee aspirants
13:59 ....it moves in a crazy way😁
Very Famous lecture of Sir Walter Lewin....Now I got to know why it's famous....
PHYSICS WORKS! AND I AM STILL ALIVE!!!!
This gives me Goosebumps sir....Loads of Love
Professor, can you please tell me where can i find assignments given by you based on these lectures. (your lectures are just amazing. I have never seen such an enthusiastic PHYSICS professor like you so far in my life )
they are listed below the video thumb nails. Also exams and also solutions
Professor i have a request if you can give these lectures in hd quality i will be more happy. and I wanted to say thank you for the way you teach physics. I'm not a physics student but recently I've been watching your lectures and the way I look at the world is not the same anymore and it's amazing. Now I love physics.
My vintage MIT course lectures are from 1999, 2002 & 2004. This was at a time that there were NO online courses yet. My 8.01 lectures were on MIT TV already in 1999 and my 8.02 lectures in 2002. These lectures were among the very first on MIT's OCW. Ofcoz, our equipment was very primitive compared to 2018. But the power of these lectures has not changed. The power is not in the resolution.
For anyone wondering at 1:44 : dx/dt = v, then multiply by dt to get: dx = v dt
Every time I watch this video, I find answers to my questions.
When you didn't pay attention in Calculus I and have no idea what's going on: 2:51
LMAO was about to comment the same thing
😂😂😂
Yes, it should be the other way: learning calculus along with physics...
That's my approach to life
Watching a video each day makes my life better ❤️🤩
3:53 those dots 😮
Last Moment.. Makes me alive back enough to inspire the love I have been seeking for Physics.
Hi Thank you very mush for this great help , why always we put the acceleration is constant
we don't always assume that a is constant.
Since we often deal with gravity, we then always use the constant g=9.8 m.s^2
Lots of love from india we want teachers like you in india .....hats off to you sir..
Sir why it is said that work energy theorem is the scalar form of Newton's second law of motion?
Work is a scaler and energy is a scalar. The work energy theorem can be derived from Newton;s 2nd.
Great fan of ur teaching sir STUDENT FROM INDIA
Hi professor. Many thanks for your videos. I wanted to ask you (minute 40:45 ) why the sign of the "dr" within the integral is not negative, since the force is in the opposite direction ( the force is to go from R to Infinity according to your drawing and the movement is to go from infinity to R)
Thank you very much in advance and for all your lessons, they are really useful !
dr is by definition in the direction of increasing r.
Professor Lewin, I have 2 questions: 1) Am I correct in thinking that Conservation of Mechanical Energy would not work if we chose to invert the y axis (e.g.: as y decreases, the value for U increases)? And 2) Why does Conservation of Mechanical Energy apply when gravity is not the only force acting on the object (such as with the pendulum where there is a tension also acting on the weight)? I cannot thank you enough for your part in making this top level education available to everyone and for taking the time to answer our questions.
+Matthew Davy (1) The conservation of mechanical energy is independent of your coordinate system. (2) The conservation of mechanical energy is best expressed in the Work Energy Theorem. The work done by ALL forces that act on a mass m in going from A to B is
KE_B - KE_A. In the case of a pendulum the tension does NO work as the tension (force) is always perpendicular to the displacement of the bob. In the case of a freely moving pendulum (ignoring air drag and possible friction), only gravity is doing work. If the bob changes its vertical position by an amount h, then the work done by gravity is mgh. This can be positive or negative depending on the sign of h.
+Lectures by Walter Lewin. They will make you ♥ Physics. After some honing of my intuitions and ensuring my signs are all correct, I think I am understanding the first point. And thank you for the clarification on the second. Have a great day!
47:48 the look on the guy's face
That's me in physics class lol
@@Rubmybootyandfeedme If that were you, you would be 39 yr old now.
@@lecturesbywalterlewin.they9259 Lol, well I didn't mean that it is literally me, I meant that it is the same expression on my face when I am in physics because I have found it very hard to understand :) You are a great professor by the way.
Whoa!physics work and I'm still alive,literally killed me lmao
Surpassing and legendary talent to give fine and sound understanding to the new students of Physics.
Thank you very much professor, now i can solve each and every problem mention in the assignments.
:)
Sir I am fan of your teaching style
Sir Walter Lewin
I listen first time your name from Sir Namo Kaul . I am very very thankful
Respected sir . Don't Mind
Sir I am from India.I am in class 11
Sir this level of physics you are teaching in college but sir in India this level of physics have been taught to class 11 students . So you should teach more high level of physics ????????????😊
Its basics bro.....
Well i am preparing for JEE
@@Anonymous-lw4nq fayda hota hai bhai sir k videos se?? aur kaun sa channel dekhte ho physics k liye
@NetroHack guys i wanna know where can i get all lectures of prof walter lewin
I am also preparing for JEE
Professor I'm a Commerce student from India.. I just love you
34:18, Gravity sucks....I like that:):)
:)
He ment gravity sucks things
h=2.5r for the roller coaster works only in the case of sliding motion, the rolling of the ball takes up part of the initial potential energy and thereby reduces the kinetic energy at the point D for looping the loop
The last example of P.E and K.E in this lecture was the example which changed my life totally, Because i saw Pr. Walter Lewin First time in my life on phone while he was demonstrating this phenomenon really Since then my understanding towards world is totally changed 😊. Love you Professor ❤️
That's GREAT!!!
sending love and thanks from India for your great effort.
Hats off to you
Thank you so much sir for uploading such an amazing lecture.
Besides being interesting it made all the concepts very clear and it was really helpful in preparation. 😊
Your teaching style is amazing and anybody can understand the actual meaning of physics.
:)
Professor Lewin, did physics come easily to you, or did you struggle when first acquainting yourself with the subject? I love math a lot, and I love physics; I am majoring in math and physics. I am having a difficult time "thinking like a physicist." Was there a time when you were first learning physics that the subject was difficult for you?
ever heard of richard mueller ? his answer on quora might help you
What a magnificent genius teacher!
You could make a fun problem out of analyzing the motion of a helicopter during an autorotation. The v-square term really helps in determining where the helicopter ends up.
Sir loved your lecture. This concept helped in clearing jee advanced, India's most prestigious high school exam . I wish I will meet you when I will come in MIT for masters.
Thank you once again
Love from India
Man hasn’t Walter sir retired?
@@Ad-tr9rl yes of course
I'm here first 🥇 time to watch your video and I'm impressed 🤝.
Love from 🇮🇳
Why at 46:35 the glass was broke? He was also released that bob with 0 speed from that point?
Sorry he was actually giving a little pit push which of the cause of breaking the glass.
Een klassiek vakman zonder tierelantijnen en precies de docent zoals die moet zijn, duidelijk en gedoceerd, afgerond met een aansprekende demonstratie. Bijzonderder hoeft het niet te zijn.
Ikwas 3 maal op "De Wereld Draait Door" - de videos zijn op deze youtube channel.
@@lecturesbywalterlewin.they9259 U wilt zeggen, dus best wel bijzonder,.. Wat mij opvalt aan uw colleges is dat de studenten geen vragen stellen of komen met opmerkingen, is dat vanwege de videoopname? Ik was altijd nogal een vragensteller, vandaar
Sir ,You've greatly magnified my passion for physics...Well Wishes from India..👌🏻
at 40:40 force done by Walter Lewin and dr are in opposite direction so there should be a minus sign there, kindly shed light on that sir
I finally got it , dr is by definition positive
I just wanna say that I love you, at the moment you are a God to me.
In reference to the experiment starting at 48:00, is another reason why you didn't get hit by the ball because energy cannot be created only converted? So eventually, if you left the ball swinging, it would stop? A bit like perpetual energy?
I'm really enjoying your physics lectures, and have been watching them in my spare time. I am planning on rewatching, and taking notes, so I can understand more.
Never thought my fear of physics will be converted to love for physics with just one video !
Teachers who makes physics boring are real criminal !
Thank you sir for making me fall for physics !
Sir,In example at 5:43 ,the given condition is that Velocity at A=0=Velocity at B,so how does that object can move that height h with zero net force(as Force by F and force by gravity gives zero net force)
Please explain it sir
Sir,also what does it actually mean when in physics it is said that "an object is displaced "slowly" by some force F"(For example it is used in the definition of electrostatic potential )
work energy theorem.
Work energy theorem - B is H higher than A. KE at A and at B are zero. Work done by me is +mgH work done by gravity is -mgH. Net work is zero.
Thank you sir for clarification.