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This video is chapter 6 in my series on special relativity, and it covers the topic of relativistic addition of velocity: aka, how things that are moving relative to one inertial reference frame, which is moving relative to another reference frame, what speed or velocity are those things moving relative to the second frame. We’ll show this using the Lorentz transformation of moving worldlines, enacted with a mechanical minkowski diagram, aka mechanical Lorentz transformation, aka spacetime globe.
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Minute Physics provides an energetic and entertaining view of old and new problems in physics — all in a minute!
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Thank you for this. Due to corona making all my classes online. My class on special relativity and related subjects has been entirely just "read the book" kinda stuff. Really love the fact that there are explainations like this that help provide intuition for topics like lorentz transformations, lorentz invariance, and relativistic addition of velocity.
Oh boy time to confuse the AP Physics 1 students by telling them to launch an object at 50,000 km/s while going 250,000 km/s
This guy needs to slow down
I sincerely want to ask.. isn't this puzzle that, everything we see in this world is bcoz of light hitting our retina at a speed of 299…km/hr.
Wat if sm other organism has sm other sense which can percept particles faster than speed of light… Then speed more than c is possible. If this is true then in twin paradox even if time measured by both would b different, the difference in aging would only b bcoz of change in gravitational conditions, physical conditions etc.. But not at all bcoz of time.. It's just dat they measured time differently… Which they can always match back…
Plz if sumone wud like to respond…
Wow. I was calculating the formula with normal velocities, just to see how much different it is from simply adding the two normal velocities together and here is the result.
If you ride in a train with the velocity of 50 km/h and you throw a ball in the direction the train is going also with the velocity of 50 km/h, then the ball will fly with the velocity of 99,999999999999785665294924554643 km/h.
Hi. Do you have a video explaining why the speed of light is constant?
0.6c + 0.6c is not 1.2c ,cause you have decided to make C as constant and 100% meeting the X axis. But relativistic speed of light is still possible. you can exceed speed of light. Infact what so special about the C number that all observers feel the same.
Where's mass increase coming into play?
Why experiment is important in physics explain in full detail.
How is the 1+vu/c^2 at the bottom of the equation derived?
Why speed of light is constant ?plz make video on it.i can't find it on yt
What I Understand ……………… C = Speed of light
Can you please show us from where the equation comes , I mean the proof of the equation .
https://youtu.be/ugjkTB__6nU
it's confusing. this "speed perspective" is not because the space time itself is expanded right? like how we perceive a distant galaxy, since that distant galaxy let's say, static?
so that why that static distant galaxy is moving more than the speed of light
Where did you get that thing? I want one too.
if we see sound, then cosmic speed limit for us is 330ms^-1, no
First, you are moving, but that's not important right now. You're making a false assumption which has led to a schism in uunderstanding how acceleration and velocity works. To wit, you confuse Rate – the effort involved – with Time. Terrible fallacy. I mean, come on. Light speed is not infinity, so your statement about it must be false. Do you not even remember whhen you yourself said that while traveling ahead on a train does not simply add your speed to the train's speed to make the total speed, but that there was still a positive acceleration? The Given in this equation you put forth is incorrect. You don't KNOW how the universe actually works because you cannot properly TEST it. Experiments up until now have been too small and too much supposition to get anything definitively true, and things in nature fly in the face of conventional knowledge, leading one to the inevitable conclusion that we do not actually understand enough.
Once again, this explanation, like so many others, gives the impression that "relative" velocity is a "real" velocity. And this is where these explanations always go wrong. Firstly, to get a more logical understanding of the subject, start by replacing the word “relative” with the word "perceived". From the beginning, the narrator is already talking about the velocity “perceived” by an external observer as if it is the “real” velocity. But don’t forget, the “real” velocity of the person firing the pellet is still 0.6c, the “real” velocity of the pellet is still 0.6c. That didn’t miraculously change. It is just the “perceived” velocity that “appears” different to the external observer. Secondly, ask yourself why the Lorentz Transformation incorporates the speed of light? Because the equation is meant to be used by an external observer to measure or predict the “real” state of an object in a moving frame of reference and light is what that observer uses to “perceive” the object from their own frame of reference. It should not be used to conclude that the “real” velocity of an object can never exceed the speed of light, as the video seems to purport. On the contrary, the correct conclusion should be that the Lorentz Transformation can only be used for measuring objects with a “real” combined velocity less than the speed of light, because the observer is limited by the light needed to perceive them. Other equations, perhaps using red and blue shifts, may permit to extend that limit. But always remember, “Relativity" does NOT equal "Reality".
Question: if you have something moving faster than the speed of light relative to you, and you're moving 60% the speed of light to someone else, how fast is the object from their perspective?
Crothers, S.J., Special Relativity and the Lorentz Sphere, Physics Essays, V.33, No.1, p.15, 2020, http://vixra.org/pdf/1911.0013v2.pdf
Abstract: The Special Theory of Relativity demands, by Einstein’s two postulates (i) the Principle of Relativity and (ii) the constancy of the speed of light in vacuum, that a spherical wave of light in one inertial system transforms, via the Lorentz Transformation, into a spherical wave of light (the Lorentz sphere) in another inertial system when the systems are in constant relative rectilinear motion. However, the Lorentz Transformation in fact transforms a spherical wave of light into a translated ellipsoidal wave of light even though the speed of light in vacuum is invariant. The Special Theory of Relativity is logically inconsistent and therefore invalid.
So, would it be fair to say that the speed of light could be considered as 100% possible speed? Therefore, traveling at 60% speed of light and firing a death pellet at 60% speed of light once over would instead be calculated as 60% speed of light plus 60% of that speed, aka additional 36% of the speed of light? So it's a multiplicative addition, not an absolute one. Going by that logic, though, it would seem that it's not possible for any material thing to achieve speed greater than 50% the speed of light, or else it would be possible to surpass it, by propelling another on top of that. In other words, nothing able to propel another thing can at the same time be able to go at more than 50% the speed of light? I'm interested in knowing whether it's provable that a material object capable of carrying another object can theoretically travel at more than that speed.
As much as I understand the fact that "they don't exactly add up", I still can't really conceptualize it.
It makes sense from the spacetime globe and from the equations that nothing can go faster than the speed of light, but that's because the equations and spacetime globe were specifically designed around that result. How do we know they're right? Is the universal speed limit an experimental result? How do we know we just can't measure anything faster? (I'm genuinely curious and also playing devil's advocate)
Honestly, I'm so used to sci-fi jargon, I didn't even think twice about "death pellet" until I read the comments.
LOL we don't need brilliant. We already have the intuitive understanding because of YOU! 🙂
I wonder, whats the speed of a photon relative to the Frame of reference of another photon traversing in the same direction
But WHY CAN'T WE TRAVEL FASTER THAN 'c'??????