Ever wonder how Einstein proved E=mc²? This is how.
Pi day (3.14) is Albert Einstein’s Birthday! To celebrate, we’ll explain 4 of his most groundbreaking papers from 1905, when he was just 26 years old.
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稍微理解了，去年我们的高一物理老师放了类似的视频我都没懂！
主播牛逼
Einstein meets cat squared.
Since the cat is squared, it must be Picasso's cat instead of Schrödinger's.
Understandable
if the fastest thing in the universe is the speed of light, how do you square that? Ain't gonna get it on you tube.
Einstein didn't even know that E=mc^2 could be derived from the equations that he plagiarized from Lorentz until someone else pointed it out to him.
E=mc^2 had already been derived by other methods prior to this already.
Energy = mass * cat^2
wonderful explanation
Beautiful, then explosive
In either case that cat is dead!
trash video
Einstein did not write the exact formula E = mc2 in his 1905 Annus Mirabilis paper. 'E = mc2" was adopted by the wider scientific community – https://en.wikipedia.org/wiki/Mass%E2%80%93energy_equivalence#:~:text=Einstein%20did%20not%20write%20the%20exact%20formula%20E%20%3D%20mc2%20in%20his%201905%20Annus%20Mirabilis%20paper
Einstein's inertial mass (Eo/c2) is used to form E = mc2.
"IT is clear from our previous considerations that the (special) theory of relativity has grown out of electrodynamics and optics." (Einstein, § 15).
"Hence we can say: If a body takes up an amount of energy Eo, then its inertial mass increases by an amount Eo/c2 " (Einstein, § 15).
The absorption of a photon by a body was said to increase the inertial mass (Eo/c2) of an object which was used to depict the quantization of Maxwell’s electromagnetic field into a photon but the absorption of a massless photon by a body does not increase the mass of an object; consequently, m = 0 and E = mc2 = 0. The energy-momentum,
E2 = (mc2)2 + (pc)2…………………………………………..36
is used to justify Einstein’s energy equation E = mc2 where the photon rest mass (m = 0) forms,
E = pc = hc/λ = hγ…………………………………………..37
But the term m = 0 that formed E = pc (equ 37) produces E = mc2 = 0. In addition, the photon energy (hγ) is represented with the units of the kinetic energy (g . m2 / s2 ) since h = 6.55 x 10-27 erg . s and erg = g . m2 / s2 yet a photon is massless. Compton's photon momentum (p = h/λ) was used to justify Planck’s photon energy equation hγ but a radiometer does not function in a vacuum. Crookes (1873) radiometer was used to justify the photon momentum but the Cookes radiometer is an open system (fig 12). Nichols' (1901) radiometer was used to justify Compton's photon momentum but Nichols radiometer is also an open system (fig 13). The NASA Solar Sail (ACS3) is used to justify the photon momentum but the negative result of the radiometer in vacuum proves the NASA solar sail is fictional. Plus, Einstein’s energy equation E = mc2 is a systemic problem since, in modern physics, the electric (m ⋅ kg ⋅ s-3 ⋅ A-1) and magnetic (kg ⋅ s-2 ⋅ A-1) fields are represented with the unit of mass (kg) yet electromagnetic fields are massless; consequently, massless photons can produce a force or momentum which voids Einstein’s energy equation E = mc2.
I know it's omitted for the sake of brevity, but would be nice to know why we think the cat's kinetic energy is different when we accelerate to v before and after the flash
Men 🔥👑
Women ☕🤡
𝙑𝙑𝙤𝙢𝙚𝙣 𝙧 𝙏𝙧𝚊ട𝙝
0:49 If the emission of the light does not alter the motion of the cat why should the observer in the spaceship measure a decrease in kinetic energy?
man physics is too easy and science biology when can it be harder
hold on but i thought that E = mc^2 wasn't even the whole equation because light has no mass and it still has energy?? isn't there something with momentum?
Shit teacher
Actually understanding this gave me a brain blast
Yeah right, exactly what i thought
Point of perspwctive doesn't effect an event. That part of relativity is a joke.
Oh ok
… that he ALSO derived … this is something that is derivable in plain old mechanics … mind you, not trivial … hence, … you know:: Einstein
A great communicator 🙂
Instructions unclear, now I have a radioactive cat.
But what about weight object still has energy
Wow. I had no idea the proof was this “simple”. That Einstein guy was pretty smart.
Talking to fast
Best explanation ever😃😃😃
1:47 that velocity is constant, because you are in the same ship moving at velocity V, which at the end does not matter, because all the V^2 cancelled out. Mathematics is like a beautiful human, attractive, painful to understand, hard to learn, very useful and you cannot live without it.
Thank god you got better at this cause these past two minutes might be the confusing I’ve ever experienced
One of the worst explanations of this formula I ever encountered. What makes it even worse is that it is correct.