Can you PROVE the most Famous Equation in Physics?
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- Опубликовано: 23 май 2019
- A Simple proof of E=mc2 can be shown by a thought experiment, which goes as follows :
Imagine a container floating in deep space away from any external forces. If a light bulb inside it emits a beam of light, the container should experience recoil, as the light beam carries momentum. This is necessary for the Conservation of Linear Momentum. However this sets the container in motion which cannot be; as it will violate Newton's First Law which says that isolated bodies at rest will be at rest until an external force acts upon it. So, Einstein proposed a solution that the motion of light (which has momentum) is also associated with the motion of a small amount of mass, so that the final Center of Mass of the container+photon system does not change. Doing necessary calculations lead to E=mc2
E=mc2 or the Mass-Energy Equivalence Principle is probably The most famous Equation in all of Physics. It gives a quantitative relationship between Energy and Mass. Anything that has mass, will have an equivalent energy associated with it and any form of Energy will have mass associated with it. Converting one from the other is an experimental problem. The Equation merely states that the relationship between them when such a conversion happens, what should be the necessary relationship.
Here, in this video I discuss the simple yet elegant thought experiment of Einstein that can be used to show that E=mc2
#thoughtexperiment
𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬𓏬
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PLAYLIST ON Special Theory of Relativity
• Special Theory of Rela...
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1. History of Special Relativity ► • History of Special Rel...
2. Michelson Morley Experiment ► • Michelson Morley Exper...
3. Special Theory of Relativity ► • Special Theory of Rela...
4. Time Dilation (Thought Exp) ► • What is Time Dilation?...
5. Length Contraction (Thought Exp) ► • What is Length Contrac...
6. Lorentz Transormations ► • Derive Lorentz Transfo...
7. Relativity of Simultaneity ► • Relativity of Simultan...
8. Can you prove E=MC² ► • Can you PROVE the most...
-----------------------------------------------------
9. Special Theory of Relativity ► • Special Theory of Rela...
10. Length Contraction ► • Length Contraction (Sp...
11. Length Contraction of Inclined Rod ► • Length Contraction (& ...
12. Time Dilation ► • The Mind Bending Predi...
13. Muon Decay Experiment ► • The Mind-Blowing Proof...
14. Relativistic Velocity Transformations ► • Derivation of Relativi...
15. Speed of light in moving medium ► • Speed of Light in a mo...
16. Relativistic Doppler Effect ► • What is Relativistic D...
17. Relativistic Mass? ► • What is Relativistic m...
18. Relativistic Kinetic Energy ► • Relativistic Kinetic E...
19. Relativistic Force ► • Relativistic Force
20. Relativistic Energy & Momentum ► • Relativistic Energy an...
21. Magnetism arises from Relativity ► • The Hidden Connection ...
22. GATE Physics question ► • GATE Physics: Problem ...
23. TIFR Physics question ► • TIFR Physics: Problem ...
24. Question on Volume contraction ► • Volume Contraction in ...
25. JEST Physics question ► • JEST Physics: Solving ...
26. NET Physics question ► • CSIR-NET Physics Probl...
27. Spacetime Invariant Interval ► • SPACETIME Interval & i...
28. Minkowski Spacetime ► • Minkowski SPACETIME, H...
29. Eucledian Space & Minkowski Spacetime ► • 5 Main Differences b/w...
30. Spacetime Diagrams ► • Time Dilation, Length ...
31. Four Vectors in Relativity ► • What are FOUR VECTORS ...
32. Doppler Effect using 4-vectors ► • How to use 4 VECTORS t...
33. Compton Effect using 4-vectors ► • How to prove Compton e...
34. Particle Decay using 4-vectors ► • Particle Decay in Rela...
35. (SHORTS) Does Light experience time ► • Does light photon expe...
36. (SHORTS) Light for moving observer ► • What is the speed of L...
37. (SHORTS) Nothing can travel faster than light ► • Why nothing can travel...
38. (SHORTS) What is farther away ► • What is farther away, ...
Special Theory of Relativity ► ruclips.net/video/OqhsiylAsFI/видео.html
I have some points to make; there is no place in the Universe where gravity does not affect. So, the cointaner will have to be considered as a being acted upon by gravity; light has kinetic energy but has no mass. Also, energy of light does not depend on its intesitiy but on its frequency; h bar times f.
When you shoot a gun there is a recoil and the bullet does not reach the maximum speed instantaneously but accelerates. And we know that the cause of the bullet's acceleration is the exploding gun powder in the chamber of the gun. So, what is ''exploding'' to give acceleration of light that is traveling at c in the container for light cannot reach the speed of c instantaneoulsly? Nothing happens in zero seconds. Also, the kinetic energy depends on the frequency of light. And kinetic energy is 1/2mv^2. Therefore, the equation contains mass and mass is not kinetic energy. In order to calculate kinetic energy from the equation there must be mass included in it. Also, the momentum turns into force when the light hits the target which can be expressed in -F=ma. Or -F=pa/m. But light accelerates from point A to B like the bullet that accelerates from the recoiled gun. But as you say that light starts traveling from point A to B and let's say that no forces act upon the container, the light cannot begin traveling at maximimum speed even if it is c but slower because it has acted on point A which gave a push opposite of the travel of light to conserve momentum. Therefore, light has initial speed of v sub one and when it gets absorbed it has a speed of v sub 2 times acceleration. So, the whole speed of light in the container is:
V = [v sub one - ( v sub 2 x a )/1-cos theta)]/[(sqr root h bar f times c^2/2)]. Now, from calculating V do c-V = difference (let's call it D) in speed v sub 2 which is associated with momentum p at point B. And if p=E/c the substitute p=E/D which must be the momentum at v sub 2. But the would affect the number of E for energy. So, E would have to depend on either absence of gravity or on its presence. Acceleration of light cannnot be ommitted either.
Also, problem arises with delta t where there is no defintion of time. If example does not include gravity which supposedly affects time it is useless to say anything about the time as it would shoot into infinity in this example.
A photon does not have any mass only kinetic energy. Also, the energy of light does not depend on the intensity of it but on frequency and it's measured lambda times velocity which is c. Therefore, E cannot be intensity. So, if you have momentum as p=E/c then by the energy of light lambda times velocity you would have p=E times c/c which will give you lambda which alone would be momentum. So, M delta x = lambda. Then the rest of calulations change, too. Or you can use the Planck's constant h bar. And if you want to widen your calculations it's actually h bar/2pi. Something does not jibe in your explanation.
This guy is an absolutely great physics teacher , he focuses first on relying the underlying ideas and only later on the mathematical formalism. and has the very rare talent of explaining deep ideas in a straightforward manner, i would be great full to you if you could do some videos on quantum field theory
Love your voice, accent, videos, explanations, and how crisp, short and on-point all of your videos are. Great work man, really educational and entertaining!
Fantastic explanation! I was looking for something like this for a long time. Thank you for posting.
The example which is discussed here actually happened or not.
Plzz bro if you know that.
Thank you
Many congratulations on completing this milestone.. wishing you more success in the future.. You are building a wonderful channel where anybody can learn physics from good quality videos.. thank you for taking out time to make these highly educational and useful videos.. we really appreciate you..
I've seen your videos on Geiger Muller counters and Scintillators. You have earned another subscriber. THANK YOU
Great job explaining this most interesting thought experiment and how some basic physics reveals the Energy-mass equivalence (equation).
I have been watching ur vdos,when u have less than 5k subscribers,now u have more than 100k subscribers,keep growing & keep educating us
When you doing that kind of thing ....I get motivet ...and also thought that do what you want .....such a nice effort sir....and also like the way you are express the physica in a intresting and easy ways
I have seen several videos that tried to explain about e=mc2, and i don't understand, until i saw this great video.
Sir, I would like to clear a thing. Consider a big ball and a car placed inside that ball, if the car is accelerated inside the ball the ball moves too. That means the force acting on the ball is external force. you gave an example about isolated box which has a light emitting beam inside it. So, when the light emits it puts some recoil on the box can call it as a force. The force acting on the box is external force not an internal force to be clear. If the light emission is putting recoil force on box that is an external force. And coming to internal forces there are only inter molecular, inter atomic forces acting. So the light emitting producing recoil force is truly an external force.
Please provide the initial assumptions for the isolated system.
1. No gravity
2. No heat dissipation
3. Container at rest
4. Free from external force
Anything else?
gravity is also a type of external force
@@jackming7972 what is the opposite reaction of gravity?
@@sumthinfresh If you are standing on the earth there is the gravitational force mg on you downward. The opposite is the gravitational pull you are making on the earth, upward. This is equal in magnitude but doesn't influence the earth much because of its great mass in comparison. (Using Newton physics here for simplicity)
If you liked this video, here are a few more suggestions :)
1) Can a free electron absorb a photon?
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Electromagmetism doesnot exist, is a false idea just a lie,
Not scientifically possible to mix, combine or fuse in any way electrons with magnetic energy or force.
牛顿第二定律，当加速度等于0时，物体要保持原来的运动不变，就必须要克服其物体继续运动的阻力反加速度，平衡这个反加速度的一个相等的加速度存在。爱因斯坦的“能量”也只是抄袭了工程力学缺失了阻力能量、极不准确的：“E（能量）等于m（质量）乘以c（速度）的平方”地物体做功公式，以为这个物体运动公式产生出的不等E=M²C²式（速度越高质量越小），是因为“能量与质量存在互相转化”！所以就假设其中间存在一个转化媒介“量子”使其能够“被平衡”？完整的能量公式应该是“E等于M平方乘以C平方”。质量可以影响速度，速度影响不到质量。能量“消耗”的只是物质地结构（如分子结构、原子结构），没有消耗任何基本物质（电子、质子、中子，“能量”只是在改变这三种基本物质的排列组合时地“结构动态反应”动力现象。）。自然中不存在量子，宇宙不是产生于大爆炸。这不是质疑大师们的数学能力，而是其眼界和思想广度与深度的客观逻辑性地积累没有达到能够包罗宇宙所有事物。
F=ma 0=m0 ? （加速度等于零时，物体运动不需要动力？）
F=mv=-a'm=F' （物体做匀速运动时，加速度等于阻力加速度。）
E=M²C² （校正爱因斯坦缺失了阻力的“能量公式”，E=M²C² 为正确的能量等于质
量的平方乘上速度的平方。）
我在国内（包括网络上）如此讲了十多年，又在国际网络上讲了五年。没有一个专业科技人员肯公开出来讨论，甚至辩论。其一些被我点名的中国国家权威们面对他们的虚伪、欺骗、抢劫，也全都始终选择保持静默？而不是被诽谤？名誉受到攻击？却只能动用权势，在国际网络上对我提出的“国家伪统治体制事实”进行全面封杀！认为我在此种情况下（得罪了东西方文明，遭国内外共同封杀。）不敢回国去。可是我还是于2019年9月至12月回国呆了3个月，有惊无险地回来了。因为我说的是纯粹的自然科学与客观经历、无党无派独往独来，他们不敢轻举妄动并不会是害怕李辉林，而是害怕其潜规则强盗科学与真理在全世界曝光？或者在欧美的态度与其一致的情况下，他们仍然还不坦然地害怕？
【爱因斯坦晚年信精神，怀疑物质！】那是因为爱因斯坦只知道宇宙中的所有物质都是在“相对性”地不断变化，由存在到“消失”的。却不知道他们全都是由“绝对性、客观真理似的”不可被消灭或创造的基本物质：电子、质子、中子地相互关系（只存在万有引力与万有斥力地物质结构能量关系，。）与排列组合（能量只是改变物质分子结构或者原子结构所产生出的，并没有消耗任何基本物质。）而成的。以至于整个宇宙地不断变化却又永存地存在。如果爱因斯坦还健在，他看了我的“论证”，他还能如此为自己提出的“能量与物质相互转化！（并引起人类基础科学界半个多世纪虚假地猜想、臆造、欺骗。）”而迷茫吗？或者也会像整个中国的科学、文化、知识分子们及那几位华人诺贝尔物理学奖获得者那样地不敢面对，却又觊觎将其中拆零分散而获得一个个“重大科学突破”立可见成效的客观事实？
上帝从来不现身于人类，只是为人类创造了一个“三基本物质”组成的客观世界，出了一道“客观宇宙”题，如果人类还不能正确认识、解释这道客观题的结构与运算，怎么有文化、资格谈论与见到上帝？靠什么去描绘、解读上帝？难道上帝也是个希望见到什么都不会表达，只会编造花言巧语吹捧他，表示愿意为他做奴才的那种人类？人类有史以来只是我首先提出了“宇宙客观真理及关系”，就是基本物质电子、质子、中子地性质、结构、运动、变化关系组成了整个宇宙。宇宙中所有的事物，包括人类自身的物质结构与运动变化，及思想、意识、行为都是这种基本物质地运动变化所产生的。在这宇宙整体客观真理面前，人类所有的先知先觉、文化圣人们，所有所谓的科学、文化、知识都只能算是其中主观臆造或者片面客观的认识；人类所有科技、文化、知识累积到现在，都连面对、探讨这个客观真理的知识能力，甚至态度都还基本不具备。
李辉林 yes, we can definitely understand you
UNDERSTANDING TIME AND THE CLEAR MATHEMATICAL PROOF THAT E=MC2 IS F=MA ON BALANCE, AS ELECTROMAGNETISM/energy is gravity:
ELECTROMAGNETISM/energy is gravity. The stars AND PLANETS are POINTS in the night sky. Gravity AND ELECTROMAGNETISM/energy are linked AND BALANCED opposites, AS ELECTROMAGNETISM/energy is gravity; AS “mass”/ENERGY IS GRAVITY; AS E=MC2 IS F=ma. Therefore, the planets will move away very, very, very slightly in BALANCED relation to what is THE SUN. (Also, carefully consider what is THE EARTH.) Great !!! This explains the cosmological redshift AND the “black hole(s)”. GRAVITATIONAL force/ENERGY IS proportional to (or BALANCED with/as) inertia/INERTIAL RESISTANCE, AS E=MC2 IS F=ma ON BALANCE; AS ELECTROMAGNETISM/energy is gravity. Gravity/acceleration involves BALANCED inertia/INERTIAL RESISTANCE, AS E=MC2 IS F=ma ON BALANCE; AS ELECTROMAGNETISM/energy is gravity. Gravity IS ELECTROMAGNETISM/energy. “Mass"/ENERGY involves BALANCED inertia/INERTIAL RESISTANCE consistent with/as what is BALANCED electromagnetic/gravitational force/ENERGY, AS E=MC2 IS F=ma ON BALANCE; AS ELECTROMAGNETISM/energy is gravity. SO, the rotation of WHAT IS THE MOON matches it's revolution; AND objects fall at the SAME RATE (neglecting air resistance, of course) !!! Time dilation ULTIMATELY proves ON BALANCE that E=MC2 IS F=ma, AS ELECTROMAGNETISM/energy is gravity !!! It all CLEARLY makes perfect sense, AS BALANCE AND completeness go hand in hand. Balanced inertia/INERTIAL RESISTANCE is fundamental. Time is NECESSARILY possible/potential AND actual IN BALANCE, AS E=MC2 IS F=ma ON BALANCE; AS ELECTROMAGNETISM/energy is gravity !!! GREAT. Stellar clustering ALSO proves ON BALANCE that E=MC2 IS F=ma, AS ELECTROMAGNETISM/energy is gravity.
By Frank DiMeglio
Marvelous! Simply Marvelous! With all the hundreds of videos on this topic I have seen, only this video clarified the concept!
Gi sir we learn it a lot and enjoy your video thank you so much sir such a enlightening, knowledgeful, video providing for us I may feel your hard work behind this great work
Brilliant explanation and clarity!
I like the way you teach..... please continue uploading videos covering more topics...
If you can make one more video on it, I would like to watch the original derivation by einstein.
I'm an aerospace engg and too enthusiastic for theoretical physics, since years I'm struggling to understand the relativity concepts and concepts of quantum physics, specifically uncertainty principle. Would like to watch an elaborated video covering mass, light, gravity and quantum phenomenon. Thank You.
Thank you for giving such an informative and interesting lecture sir. But I have one question, doesn’t light have zero rest mass?
I am assuming that when the photon is absorbed by B , that B's energy has increased and it has therefore increased it's mass by the same value of the mass of the moving photon (because the rest mass of a photon is zero).
Thank you for this insightful lecture!
Will you ever do an electrodynamics series?
You are doing a very great work. Keep it up!
You are doing it with great professionalism. Good Job ! Keep it up ☺
Hi sir, Will you please explain why we have not considered the momentum transfer to the body when photon leaves the point A, Acc to the momentum conservation, as photon leaves point A, it will transfer the momentum to the point A just like it happens in rockets, plz clarify.
absolutely awesome.. one small q. When exposing the Center of mass, why are we taking the initial points of container and the light as x1 and x2. Both starts from point x1 right?
Sir , Can you explain working principle of magnetron and klystron ? Thanks
Will the absorber at point B become warmer? If so why is not accounted for in the equation since it is also a form of energy?
A brilliant teaching way 😀
I have clearly understood the equation
A very very thank you to you Sir 😊
Sir, please create playlists for all videos....
Very good explanation. Thank you very much.
i hope you reach 1M subscribers. you deserve it. thank you for all your videos, i hope you continue to make many many more
Sir thank you so much I like the way you explain the concepts of physics
What is the location of X1 and X2 in your diagram? Thanks
sir can you make a video on relativistic mass and rest mass . it's very confusing
Sir energy is the capacity of body to do work ...then what will be the interpretation of this E in E=mc^2
Excellent, please keep posing such videos .
Excellent. I am now more clear on this. Thanks.
Sir, what will happen if we perform this thought experiment in space after getting too kuch facilities...and during performing, photons couldn't push the container in backward
Will we prove Einstein wrong???
Thank u for excellent explanation.
Brilliant explanation...
Very helpful...
Actually, what you have derived is a relation
m = P/c
where m is a mass of a moving object (a ball or a photon), c - its speed and P - momentum of a container (and of a ball/photon respectively, due to momentum conservation). It suffices to put P = E/c for photon to get what you want (or another relation for massive particles in case you have one). It has Newtonian form (p = mv where v is substituted by c) although you are dealing with special relativity here. Does it constitute a problem?..
I'm with you till end of the line sir, my first encounter with you sir was in the video related that an electron cannot stay in nucleus which has to be proved by using Heisenberg's uncertainty principle.
Good night sir.
Superb Sir
It is looking now simple after your explanation
Very clear explanation. One tiny improvement is that the term intensity is not exactly equivalent to energy. Intensity has its own definition in physics. But all these is minor.
At time 08:35 velocity v of the container is written as a constant DeltaX/Deltat. That would imply infinite acceleration and infinite impulse. In reality, it will take some finite amount of time for velocity to go from zero to v. This should have been addressed.
Great video. Can you help me understand why external forces are needed for something to move? If I replace the light pulse with a bullet from a gun, the box should move, then stop when the bullet hits the other side, right? There was motion without an external force. What am I missing?
There were motion in both directions, net momentum = 0 all the time. So the systen as a whole is not moving.
here is an interesting derivation using the time dilation expression of STR: we have t(v)=t(0)*(1-v^2/c^2)^1/2. we write this as frequency 'f', which is defined as frequency = 1/time. hence we have f(v)=f(0)/(1-v^2/c^2)^1/2. for constant 'v' we have df=df(0)/(1-v^2/c^2)^1/2. we have dE=dP/dt *dx or dE*dt=dP*dx=k. this gives us dE*dt=k and dP*dx=k. from these one can obtain the heisenberg's uncertainty expressions. however, if we take dE*dt=k and write it as dE=k/dt we get dE=k*df, because df=1/dt as frequency = 1/time and for frequency = df we have df = 1/dt where dt = time. from dE=k*df we obtain E=kf+C where C is the integration constant. if when f=0 we have E=0 then C=0. hence, E=kf. of course from we can shown that k=h and obtain the general expression E=hf of which the planck expression for energy quanta or photon is a special case. hence E=kf(0)/(1-v^2/c^2)^1/2. from E=kf we get E(0)=kf(0). hence, E=E(0)/(1-v^2/c^2)^1/2. again for kinetic energy E(KE) we have E(KE)=E(v)-E(0) or {E(0)/(1-v^2/c^2)^1/2 } - E(0) = E(KE). for v
Which camera do you use to record video?
When light hits B', will the momentum transferred make the isolated box to move to the right side ?
Sir can we get your notes in soft form?
How does light have a momentum whats momentum is mass×velocity so light is Massless then why we measure momentum of light plzz sir answer it
Wonderfull.Marvelous teacher
Thank u bro. It was really excellent class for me.
I've learnt a lot thank you.
Fantastic explanation...!!!!!
thank you very much it is a very good proof. But why them momentum of a photon is equal to E/c? shouldn't it be 2E/c?
I'm very impressed !
Beautifully explained without even mentioning time dialation.. felt like you took us on a Ferrari ride.. built by Einstein, but you were on the wheel!
Thank you so much Sir!
Sir , without any external force how the photon was generated??
If del x is equal to L then what's the need of centre of mass and all
Yeah its a very good derivation sir.
Although Its only valid for objects at rest.
Its still incomplete what u hv written.
Pls provide the full derivation E= gamma mc^2
Yes. The generalized formula with Momentum term.
p=mv m-relativistic mas. For light v=c so for light p=mc . If you assume that E= mc*2 then p/E=mc/mc*2 p/E= 1/c p=E/c You are using equation E=mc*2 to derive equation E=mc*2
In space an object has to continue to move as no force is applied then how did the container came to rest after emission of light is not happening
Because the photon moving in opposite direction hit the container and cancelled its momentum
you're the best physics teacher I've ever had! thank you sir
Sir,where can i get your printed notes?
I have two questions. If A and B are in fixed position then the small m must travel all the way to B even if it moved to left.
Secondly if I switch on a 500 W bulb in my room will the room shake?
No, because in this case friction force will come and it greater than the recoil force.
Sir i have a question....you said that the light or energy has mass thats why it shows recoil, that container slightly moved backward then why not the other side move forward where the light striked on the other end of container as light carries the mass😅
at 13:30
1st, the mass associated with the motion of the light energy -- you are already assuming the mass becomes the light, then the light becomes a mass upon hitting the point B. one way to view for a matter to travel at the speed of light, then rematerialize itself
2nd how can the point B instantly move as a light is emitted from the point A?
at 15:26 ...CM is unchanged.., only because of the laws of physics momentum must be conserved FIRST. MV=-mC = M (x2-x1)/t = -m(L2 - L1)/t, Mx2 +mL2 = Mx1 + mL1 , not the other way around, with which simply gives MV = m L/t = m c = E/c
Fantastic explanation
Actually knowlegble video
Thanks Sir
Sir, in one place I have doubt. Initially you said that light is emitted internally.But How light will emit inside a container automatically. If we one it remotely than it means externally is force is applied but you said no external force is applied. How???
In some forms of radioactive decay (I think gamma decay for example) a photon can be emitted.
So our emitter at point A could be some radioactive material that decays and therefore emitts photons "automatically", with no need for an external force.
Because the Sun is an Sphere ???
Thank you so much 💓
I think we can also prove this by the contraction of length 😉
Is the example you have told actually happened or not.
Plzz sir I am still confused.
But sir explanation is mind-blowing.
Thank you very much.
Very nice video and clearly explained! However, I have a (possibly stupid) question. In the thought experiment why can't you replace the light beam with an object with arbitrary speed? Does it have something to do with the zero mass thing.
Exactly! You can! If it wasn't a photon travelling from one wall of the container to the other but, say, a golf ball pushed by a spring attached to the left wall and being glued to the right wall upon arriving there, then the container would have also moved as a result in exactly the same way - because the center of mass of a closed system must remain stationary. It's the same physical process in both cases. What would have changed however is this momentum-energy relation (E=pc) which we used in case of photon and which is not valid in case if a material ball.
Very Interesting. Explanation is very Clear. Thank you I am from Sri Lanka.
I have other kind of derivation on my own, I am getting the final answer but there is something wrong in the derivation of mine
Absolutely outstandibg explanation god bless you❤️
I really appreciate the teaching, great video!!
But I have one question. Initially you said the momentum is given by, p=E/c, but momentum is mass*velocity, ie mc (because c is the velocity here). Then we get mc=E/c => E=mc^2. So are we indirectly using E=mc^2 to prove E=mc^2. Isn't that circular reasoning?
I am not a student of physics, but a student of economics, so I might be mistaken about momentum etc. How would you clarify this doubt?
p=E/c comes from wave equations for radiation/light. p=mv comes from basic mechanical concepts for particles with mass. Both have separate origins. The genius of Einstein was to equate the energy of radiation to that of the mass of a particle/photon. In terms of equations, it's nothing significant, but in terms of physical concept that involves the matter-energy equivalence of light, its a great breakthrough.
@@FortheLoveofPhysics Thank you sir
By De broglie principle about matter lke electron or photon that display wave nature ........P = H/^ De Broglie relation
p= H/^ relationship between momemtum p and ^ wavelenght of particle
P=H/c/f..........................C = V=F^
p= HF/C
P = E/c ( E = HF.....by plank )
@@goriolaganiu403 In 1901 Plank developed his equation and in 1905 Einstein developed his Mass energy equivalence formula.. Then in1923 de broglie developed equation related to matter & wave.. Don't try to prove Einstein equation with plank and de broglie equations..
@@ishankashyap3350 I appreciate your objection. It's food for -fart- thought
sir i kindly request u please make a video on ' parity, baryon number, Lepton number, Isospin, Strangeness and charm, concept of quark model, color quantum number and gluons '.
Will do soon..
@@FortheLoveofPhysics plz do it
What a nice explenation...👏👏👏
I'm getting very confused at the part where you explain how the center of mass remains in the same place. You put out the equation (m1x1+m2x2)/m1+m2. I don't understand how you got there.
That is the equation for center of mass
Sir I'm always in confusion of that how we 'll able to travel in time if you have some idia aur your experience about.. And if you will share it with us. That will really mean to world for me...... The physics lover
Einstein’s idea of time travel comes from the theory of relativity with the idea of time dilation.
1.Why you ignore the mass of source emitting light?
2.Why have you assumed speed of container to be uniform ??
3.Why have you taken x2
Even if rest mass of photon is =0.
I think thar the speed is uniform because there is no force acting there so the aceleration=0.
great sir , for the sake of celebration you are doing one more proof ! true love for the physics . and sir it was really very interesting to proof E=mc^2 in this way and the suspense you created in the video i was like how Einstein sir solved the problem 🤔
Thanks. I am glad u liked the video :)
For the Love of Physics , thank you so much. Great job. Please keep it up and educate the students around the world. Where do you work ? Please
@@FortheLoveofPhysics Greetings. Reply please.
WHY THE ULTIMATE, TOP DOWN, AND CLEAR MATHEMATICAL UNIFICATION REGARDING PHYSICS/PHYSICAL EXPERIENCE IS F=MA AS E=MC2, AS ELECTROMAGNETISM/ENERGY IS GRAVITY:
E=mc2 IS F=ma. Gravity IS ELECTROMAGNETISM/energy, AS the Earth AND the Sun are CLEARLY linked AND BALANCED opposites; AS E=mc2 IS F=ma. ACCORDINGLY, the stars AND PLANETS are POINTS in the night sky; AS the MIDDLE DISTANCE in/of SPACE is linked AND BALANCED to/with/AS what is the FULL DISTANCE in/of SPACE !!! This necessarily represents, INVOLVES, AND DESCRIBES what is possible/potential AND actual IN BALANCE, AS E=mc2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. ("Mass"/ENERGY IS GRAVITY. ELECTROMAGNETISM/ENERGY IS GRAVITY.) Gravity AND ELECTROMAGNETISM/energy are linked AND BALANCED opposites, AS E=MC2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. Gravitational force/ENERGY IS proportional to (or BALANCED with/as) inertia/INERTIAL RESISTANCE, AS E=MC2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. Gravity/acceleration involves BALANCED inertia/INERTIAL RESISTANCE, AS E=MC2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. (The sky is blue, AND the Earth is ALSO BLUE !!!) Great. Very importantly, outer "space" involves full inertia; AND it is fully invisible AND black. INSTANTANEITY is thus FUNDAMENTAL to what is the FULL and proper UNDERSTANDING of physics/physical experience, AS E=mc2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY. SO, time DILATION ULTIMATELY proves (ON BALANCE) that ELECTROMAGNETISM/energy is gravity; AS E=MC2 IS F=MA. It ALL CLEARLY makes perfect sense. Indeed, BALANCE and completeness go hand in hand. Great !!! TIME is NECESSARILY possible/potential AND actual IN BALANCE, AS ELECTROMAGNETISM/ENERGY IS GRAVITY; AS E=MC2 IS F=MA !!!
Gravity IS ELECTROMAGNETISM/energy. E=mc2 IS F=ma. Accordingly, the rotation of WHAT IS THE MOON matches it's revolution. Objects fall at the SAME RATE (neglecting air resistance, of course), AS E=MC2 IS F=ma; AS ELECTROMAGNETISM/ENERGY IS GRAVITY !!! WHAT IS THE EARTH, WHAT IS THE MOON, AND WHAT IS THE SUN ARE clearly F=ma AND E=mc2 IN BALANCE !!! Again, this NECESSARILY represents, INVOLVES, AND DESCRIBES what is possible/potential AND actual IN BALANCE; AS ELECTROMAGNETISM/ENERGY IS GRAVITY ON BALANCE !!! LOOK around. Think !!! Great !!! ("Mass"/ENERGY IS GRAVITY. E=MC2 IS F=ma. ELECTROMAGNETISM/ENERGY IS GRAVITY.) The Earth (A PLANET) is a MIDDLE DISTANCE form that is in BALANCED relation to the Sun AND the speed of light (c), AS the stars AND PLANETS are POINTS in the night sky; AS E=mc2 IS F=ma.
By Frank DiMeglio
Nice explanation sir 👍🏿
Thank u very much sir it was very helpful
sir what will be the equation when momentum is not zero
sir plz explain
Good for you, brother... Very good presentation.
I am a data scientist (well, I'm TRYING to be); I never thought I see Einstein here. But, here he is (can't get rid of this guy. I love the guy. I just don't have that much IQ); calculating matrices, tensors, etc. So, I'd really appreciate if you did some videos on vectors, matrices, spaces and ...
What happens if the photon is traveling perpendicular to the moving container
I wonder, is it as easy to derive if you assume it is not a photon being emmited but a ball being thrown?
Most wonderful teacher
He teaches physics greatfully
The equation for kinetic energy, KE= 1/2 mv^2, is very similar to E = mc^2. Leave out the 1/2 and it's still a measure of energy. So then you have KE= mv^2 and E=mc^2. c is a velocity so the two equations are very similar. Is there a way to reason from one to the other?
No, because c is not a free parameter. It's not even a physical constant. The numerical value is completely dependent on choice of time and distance units. In any rational system of physical base units c=1, so all you are really left with is E=m.
It just occurred to me that the same thought experiment could be done with Muons. They travel in a vacuum with a velocity of about 0.98C, and their Mass is 1.883531627(42)×10−28 kg. Would I arrive at the same result, E=M² ?
U R mad genius Sir.
U got my respect.
I've to edit.
I'm an MSc Chemistry
Is it possible to apply the equation to the entire universe? I am wondering if we go back in time far enough is it possible for a condition wherein m=0? Imagining the big bang, It seems to me that there may have been a point where the entire universe is devoid of matter, and comprised of energy alone. If that supposition is correct, would there be a need for space? If not, would time exist in that condition? I'm not sure about dark matter and energy and how they come in to play.
Thank you from a spirited laman.
Informative video
very well explained!
Thanks a lot👍