@nguyentuanminh5330
Dear Mr. Walter Lewin, your lectures are such a pricess gift to me during this hard time. I had always struggled with course name fluid mechanics because the teachers in my school did not explained and demonstrated as clear as you did. It help me regain my motivation to strive to become an engineer. After all, thanks you a lot!!!!.
@deveshtayal1515
Your service and dedication to teach every hungry mind is truly selfless.
@markfar4837
THATS HOW PHYSICS IS TAUGHT.....I AM COMPLETELY AMAZED...... EARLIER I FOUND FLUIDS VERY DIFFICULT TO UNDERSTAND BUT NOW I ENJOYED LEARNING IT IN THIS LECTURE......THE PRACTICAL DEMONSTRATION WERE JUST TOO GOOD.....
@danielecompangoni
Thank you very much Prof. Lewin, I have to take my final oral test in physics for engineering next Monday and after all this years of your lecture being around, you are saving my life as those of many other students ! These should be saved as hsitory of science for years to come !
@AKBARCLASSES
Thanks again sir... For the first time I have felt Fluids... Before this I had been thinking that in fluid part there is nothing but puzzles... Now I feel very comfortable in fluids.... Can't pay you against this but infinite respect will always be for you...
@slaysae
You are the best teacher ever ! I really love your teaching ! I wanna wish you a long and happy life !! You are someone irreplaceable in my heart ...I wanna meet you so badly and say how much your teachings helped me ! Also I really loved your birthday series 💕 Thank you so much again professor Lewis!
@VENOMFM123
I am in class 11 preparing for JEE advance and mains this helped me a lot This guy used to teach in MIT from the basic to advanced level this is what's makes him great in FREE
@hirensharma3979
Your lectures contain all theory demonstration and application ,looking forward to binge watch all your content
@nuclear5641
I have an answer to the swimming pool question posed at 11:20, but I also have two additional questions regarding the same. The answer to your question: The water level goes down, because if we assume that the density of the stone is greater than the density of water (a reasonable and intuitive assumption), then the stone will sink to the bottom of the pool and settle down. When that happens, the buoyant force that was originally holding up the stone before it was thrown into the water will now be shared between the upward normal force at the bottom of the pool AND the new buoyant force together. Therefore, the new buoyant force is only a fraction of the original buoyant force. Since lower buoyant force displaces lesser water than higher buoyant force, the water level in the pool goes down. (In the event that this is a bottomless pool, then the stone will keep accelerating downwards under its own weight as there is a net force pulling the stone downwards. This net force can only exist if the new buoyant force is lower than its weight, and hence the new buoyant force is lower than the original buoyant force. Thus, the pool level drops). However, I have two variations on the stone that was thrown out: Q 1. What if, instead of a stone, a fish of the same volume as the stone but of the same density as water is thrown out of the boat and into the pool such that the fish goes below the surface of the water but doesn't sink? Would the water level in the pool go up, stay the same, or drop? My (probably wrong) answer: The water level would stay the same. Since the buoyant force is neither being shared by any normal force at the bottom of the tank (as the fish isn't sinking to the pool floor) and nor is the fish accelerating downwards, there is no change in the total buoyant force, which means there is no change in the displaced water. Hence, the water level stays the same. In fact, when the fish is thrown out of the boat, for the brief moment that it is in the air, the water level drops (as the buoyant force drops), but once the fish is under the surface of the water, the water rises again by the same amount that it had dropped, thus equalizing the level. Q 2. What if, instead of a fish, a wooden block of the same volume as the fish but of lower density than water is thrown into the pool such that it floats? Would the water level in the pool go up, stay the same, or drop? My (definitely) wrong answer: The water level would stay the same. There is no change in the total buoyant force here either, as the wooden block isn't sinking to the floor. But I still feel that my answer to this last question is wrong because my inductive reasoning would have led me to believe that if a higher-density object (stone) lowers the water level in the pool, and an equal-density object (fish) keeps the water level the same, then a lower-density object (wood) would have raised the water level. But that is not what the equilibrium equations tell me. Please correct me if I am wrong in any of the above. And yes, your lectures DO make me ♥ physics :)
@pierpaolocasamassima8652
47:28 We can all admire the greatness of the MIT chalks in this shot... no wonder why they sound so satisfying
@nicklol7878
44:55 "That's the reason she couldn't get it up. That's what Bernoulli does to you" - Lewis
@emilia6067
Best physics teacher as well as the best physics YouTube I've ever come across. No one else comes even close
@sharudeva
{39:00 -->}
You said that when a hole is made in the vessel, water will flow with the same velocity as in the 'syphon case'. But what if both were done simultaneously ?
The approximation that v2~0 would not hold good right ?
@willalston9627
Um, King Hieron II was called a "virtuous man" by Machiavelli and he had a long and seemingly friendly relationship with Archimedes, and his father (a court astronomer) so he'd hardly "kill" him if he got it wrong. :P Great lecture.
@Jivolt
This is all nice and stuff but the mind blowing part is 0:49
@Megharaj_Chalawadi
Now i am preparing for my neet exam i have many boubts in fluid mechanics after this class i feel comfortable to solve problems of fluid mechanics thank you professor 😊for wonderful class love from India ❤💓
@rajeshchandrakuri5659
This is the best lecture i have found on Archimedes' principle..just wonderful demonstration.
@Dr10Jeeps
Dr. Lewin's ability to describe and draw complex principles is amazing.
@ashwanisingh6248
professor i am from i india, i love to watch your lectures , you explain practically everything. i am in class 10 but i understand everything. it creates me a passion to get phd in physics .thank you professor
@muhammadismail2300