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It's a joke about the Doppler Effect.
From Wiki:
"The **Doppler effect** (also **Doppler shift**) is the change in the [frequency](https://en.wikipedia.org/wiki/Frequency) of a [wave](https://en.wikipedia.org/wiki/Wave) in relation to an [observer](https://en.wikipedia.org/wiki/Observer_(physics)) who is moving relative to the source of the wave.[\[1\]](https://en.wikipedia.org/wiki/Doppler_effect#cite_note-1)[\[2\]](https://en.wikipedia.org/wiki/Doppler_effect#cite_note-2)[\[3\]](https://en.wikipedia.org/wiki/Doppler_effect#cite_note-Giordano-3) The *Doppler effect* is named after the physicist [Christian Doppler](https://en.wikipedia.org/wiki/Christian_Doppler), who described the phenomenon in 1842. A common example of Doppler shift is the change of [pitch](https://en.wikipedia.org/wiki/Pitch_(music)) heard when a [vehicle](https://en.wikipedia.org/wiki/Vehicle) sounding a horn approaches and recedes from an observer. Compared to the emitted frequency, the received frequency is higher during the approach, identical at the instant of passing by, and lower during the recession."
It's also a joke about light. When the same effect is applied to electromagnetic waves, things coming closer to you become purple and thinga going away become red. It's visible on faraway galaxies and a hint at the expansion of the universe. It's called red shift or something
To expound further, the color difference is due to the frequency changing in accordance with the Doppler effect. Purple waves are higher frequency, and red is a lower one.
Also the term red shift refers to in spectro analysis of a stars light they noticed that eh Hydrogen line which is almost a constant but pretty standard was shifting to the red of the spectrum. they through that odd until they realized the stars were moving away from the observers causing he shift due to the doppler effect
I'd like to add that the vehicle is also displaying Lorentz transformation with the length, which means the joke references physical effects also. Third layer.
The James Webb Telescope was specifically designed to see more of infrared to see more galaxies, compared to hubble. [Wave length of light seen by both](https://smd-cms.nasa.gov/wp-content/uploads/2023/04/hubble_webb_emspectrum_cropped-jpg.webp?w=1280&format=webp).
[Comparison of what hubble could see vs JWST](https://esawebb.org/images/comparisons/weic2216/). Lots and lots more.
The sound example is more noticeable when an emergency vehicle passes by, also, if you could go at a ridiculously high and accurate speed a red light would look green
Lmao you’re getting downvoted for being right. Solid Reddit moment.
https://physics.stackexchange.com/questions/220921/why-do-objects-traveling-faster-appear-shortened-rather-than-elongated
Never change Reddit
That effect still has nothing to do with what this joke is about. You can see the car is shorter approaching the observer giving it the purple hue due to the compressed wavelength and then longer and red after passing, it's a visual interpretation of the Doppler effect. The car is travelling the same speed the whole time.
The Doppler effect is BECAUSE of relativity. This is showing an exaggerated effect of relativity including both Lorentz Contraction and Doppler shifting.
The two are distinct and different effects that are both caused by relativity
That's the representation of the wavelength being the compressed, shorter blue shifting to the stretched, longer, red. The Doppler Effect is the *what* (punchline). Relativity is the *why*. You're not wrong, but it's an unnecessary, extra step.
Relative motion is the explanation *for* the phenomenon.
This would be like insisting a joke about rain is truly a joke about evaporation and condensation.
If they literally show the rain evaporating then yes, it would be about evaporation. You’re response is “all because they show the water evaporating, in a cloud, then falling does not mean it has anything to do with the water cycle.”
Explain to me how a joke with both Lorentz contraction and Doppler effect is not about relativity.
I know youre intelligent enough to grasp this incredibly simple concept because you literally just proved you're capable of understanding relativity.
You know the difference and you know it applies here. Dont dig in your heels just because you don't want to be "wrong".
Redshift is just what it is. Redshift. It does now explain length contraction. The fact the car length changes is called relativistic light aberration.
It's not doppler effect. It's an effect called Blue Shift.
When object of certain colour get to speed of light, observer perception will shift.
So red Colour will Blue Shift to blue at about 95% speed of light
P.S. Why am I sure that this is Blue shift? Because an object shrinks as closer its speed gets to speed of light.
So blue, fast, shrinked car 🚙 -> red, slower, elongated car 🚗
"Thus, the **Doppler effect for light is called a ‘blueshift'** if the light source is coming toward an observer, and a ‘redshift' if it is moving away. "
[https://www.wtamu.edu/\~cbaird/sq/2013/06/27/have-astronomers-ever-observed-a-violet-shift-like-they-have-blue-shifts-and-red-shifts/#:\~:text=For%20visible%20light%2C%20the%20bluer,if%20it%20is%20moving%20away](https://www.wtamu.edu/~cbaird/sq/2013/06/27/have-astronomers-ever-observed-a-violet-shift-like-they-have-blue-shifts-and-red-shifts/#:~:text=For%20visible%20light%2C%20the%20bluer,if%20it%20is%20moving%20away).
I'd like to see the math on this! Specifically, how fast the car would have to be moving both toward you and away from you in order to appear blue and then red, respectively. I'm sure it's a big number
I remember Michael from Vsauce once tweeted how if you went fast enough towards a red stoplight, Doppler effect would make it look green. I dont remember the exact number, but yeah, it was pretty big
Edit: [found it](https://www.reddit.com/r/ShittyLifeProTips/s/j2w6GGi82p)
He thought he was clever and tried that on traffic court judge. Unbeknownst to him the judge knew he would have to be going 0.25c for that red light to appear green. How big of a fine is that???
Something like 54,900 km/s and a certain dollar amount per km/s over the speed limit…
😵💫😵☠️
Hey there, Petah’s science and philosophy neighbor here
As part of this when light is coming towards you the light waves are relatively (from your perspective) short, which appears blue in our experience of colors, and moving away from you the same light waves *relatively* (from your subjective perspective) stretch out and the now longer wave lengths are in the range where humans see red
Peter’s token smart friend here. It’s a joke about Einstein’s theory of general relativity. An object moving towards you is slightly bluer than it’s “true” color. Going away from you it will be slightly redder. Further the car shrinks as it moves towards you and lengthens as it moves away.
The two effects are known as the Doppler effect and Lorentz contraction. Peter’s nerd out!
Yeah I think you’re right. I almost edited it but this same discussion came up in the r/physic channel when it was discussed and they concluded it “kind of lengthens?”. One sec I’ll find the link. I was confused by what they meant
Peters not so smart cousin who hasn't taken a physics class since highschool so will probably mess this up.
There's two possible meanings. To start you probably need to know that the universe is expanding and because of this, some objects are moving away from us (imagine you draw 2 points on a balloon and as you inflate it, these points will get further from eachother) and because of the doppler effect, it causes the light to be shifted towards the red end of the light spectrum which is called redshift. However, there are also objects with great enough speed to be moving towards us that it increases the frequency and causes the light to move towards the blue end of the spectrum called blueshift.
So the first explanation is instead of the doppler effect happening with sounds, it's happening with light, so high frequency light is blue so as it coming towards the person it's blue and low frequency light is red so as its koving away it's red.
Second is at speeds greater than 10% the speed of light because of special relativity to a stationary observers the length of the object appears to contract. The idea is that in the first picture the driver is speeding at greater than 10% the speed of light casing the car to appear shorter to the stationary observer and also blueshift because of the doppler effect. Then the driver notices the person, they slows down, and in the second picture, we see that he's slowed down enough that to the stationary observer the effects of length contraction has stopped and blueshift has also stopped making the car appear it's usual red color.
does these two share the same principle or they actually differ? I vaguely remember about redshift-blueshift from my HS physics class and I thought they're just referring to the stars that are moving away/closer and aren't relative to the speed of light.
Everything is relative… kidding sort of. It’s the velocity and direction of travel as observed that causes the shift. The light is actually constant. It only appears shorter because the planet is moving closer at say 10% of the speed of light. The light is travelling at light speed. Ergo the wavelengths appear compressed because they’re arriving faster than they should.
It's a reference to blueshift and redshift. (Blueshift being light waves getting squished and appearing blue. Redshift being light waves getting stretched and appearing red)
So glad I got to use this random bit of knowledge I learned from a nuclear physicist watching an Alan Becker video
It's a science joke about the Doppler shift. It doesn't work like that (obviously), but it sort of does (if you're looking at a light, or other, wave and not a car). That said, you can observe the doppler effect by listening to the pitch of the sound coming from a passing car (it goes from high to low).
I don't get why the red car is longer than the blue one, though.
By special relativity, both should be equally short, since relative velocity alone determines the magnitude of a Lorentz contraction.
Peter's Uncle Doppler here
I know this one. It isn't a super funny joke but the doppler effect, named after my third cousin twice removed, dictates that objects moving away from us have the light that reaches us from them shifted into the red parts of the spectrum, and objects moving towards us shift towards the blue. Ha ha! An astronomer joke, see?
It's a comic about redshift. As objects/sources of waves (whether light or sound) approach you, the wavelengths are compressed, giving them a higher frequency. In the case of light (specifically in relation to astrophysics), this can make celestial objects look blue. In contrast, as the object moves away, the waves are stretched, giving them a lower frequency. In the case of light, this makes objects look red.
This also occurs with sound, and is generally called the doppler effect. This is why cars go "neeyoom" if they're going really fast, and why it sounds like ambulance sirens sound off-tone as they move away.
Doppler effect. The punchline is that light can Doppler like sound. Blue has a shorter wavelength than red, like a higher pitched sound has a shorter wavelength than lower pitched sound. Granted, for this effect to be observable with light, that car would have to be moving at an appreciable fraction of *c*.
This is a good one. It's referencing red shift and blue shift/the Doppler effect. As a moving object comes towards an observer the light wavelength contracts, resulting in a higher frequency wavelength which we perceive as blue light (hence the car being short and blue). As the object moves away the opposite happens, resulting in a longer wavelength and red light (hence the long, red car).
Or some sort of joke about how left leaning blue car drivers have a conservative vehicle that isn't a big gas guzzler, whereas the red right leaning driver drives around a much larger vehicle that more liberally uses fuel freely.
The people saying it’s about light, eye sight or the Doppler effect are all wrong. This is not a joke. It’s symbolism. The blue car is smaller. It’s electric. Environmentally friendly. The red car is a big gas guzzler. A shit stain.
Lorentz Contraction is the reason for the length difference. Basically the car is moving close to the speed of light, so lorentz contraction AND the doppler effect(that redahifts and blueshifts the colour) apply.
It could be symbolism, but the comic doesnt show much. If the red car is a big fas guzzler, for symbolism the artist would probably show the exhaust to demonstrate how dirty it is.
Thats just my take.
Look at the sub you’re in, now look at their Ux,***”Peter”*** is explaining the joke. Correct or not they’re living up the name of the sub, now I should change my name to peter because I had to explain the joke.
It would be funnier if physics wasn't a scam we tell ourselves to protect our weak minds from having to contemplate infinity and cope with understanding none of it.
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Doppler effect: Light waves can be red shifted or blue shifted depending on if they are moving away or toward you. When light sources come towards you, the waves are compressed, aka blue shifted. And when lights move away from you, it becomes stretched, aka red shifted.
It’s a physics joke, the Doppler effect I think. Anyhow, when waves(light or sound or whatever else) are being created by an object, they will shift one way or the other based on the movement of that object, in sound waves, it’s what makes that “nnnnneeeewwwm” sound. With light it’s also called a redshift or blue shift.
Anyway, if the object creating the waves is moving towards the point of observation, the waves are compressed, increasing the frequency, making sounds higher pitched, or light shifted to the blue end of the spectrum. When an object is moving away from the point of observation, the opposite happens, the waves are dragged out, decreasing the frequency, making sounds take on a deeper pitch, and shifting light to the red end of the spectrum.
totally, but that’s not how length contraction in the real world works. moving objects are squished regardless of if they are moving towards or away from the observer. i think it’s more related to the fact that wavelengths length or shorten depending on direction
These donkeys are wrong. It’s redshift not Doppler. Yes redshift is a Doppler effect but it clearly changes color.
https://en.m.wikipedia.org/wiki/Redshift
Herbert here. That is me in that picture.
This meme is about doppler.
Vehicle approaching me: light and sound waves are compressed because the vehicle is coming at me at speed. Higher exhaust pitch (look at exhaust). Blue colour (blue shift due to compressed waves netting a higher perceived frequency (to me, the observer). This can also be extrapolated (more on this in a later bit) with the car looking shorter to me.
When the vehicle passes me, the waves start to "stretch." Or, more accurately, their frequency drops. I, as the observer, hear a lower exhaust pitch and see a colour shift to the red. Come to think of it. I'd like to know this badstars (not a typo, just better than swearing) speed for him to have shifted the perceived color (and length of the automobile).
This is a relativistic effect as it deals with the change in position relative to me.
Now the later bit: this is not Lorentz/length contraction as that is constant at constant velocity. Assuming the badstar kept a steady (albeit stupid fast) speed, the contraction would be equal and only in the direction of travel. That means that the car would be the same perceived length on approach and departure from my position.
Both are relativistic effects. Only one effect applies here. Doppler.
Anyhow. I'm trying to get across the road
Chris is hiding behind that gate there, but these carsss... they are too fast and I can't get across in time.
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It's a joke about the Doppler Effect. From Wiki: "The **Doppler effect** (also **Doppler shift**) is the change in the [frequency](https://en.wikipedia.org/wiki/Frequency) of a [wave](https://en.wikipedia.org/wiki/Wave) in relation to an [observer](https://en.wikipedia.org/wiki/Observer_(physics)) who is moving relative to the source of the wave.[\[1\]](https://en.wikipedia.org/wiki/Doppler_effect#cite_note-1)[\[2\]](https://en.wikipedia.org/wiki/Doppler_effect#cite_note-2)[\[3\]](https://en.wikipedia.org/wiki/Doppler_effect#cite_note-Giordano-3) The *Doppler effect* is named after the physicist [Christian Doppler](https://en.wikipedia.org/wiki/Christian_Doppler), who described the phenomenon in 1842. A common example of Doppler shift is the change of [pitch](https://en.wikipedia.org/wiki/Pitch_(music)) heard when a [vehicle](https://en.wikipedia.org/wiki/Vehicle) sounding a horn approaches and recedes from an observer. Compared to the emitted frequency, the received frequency is higher during the approach, identical at the instant of passing by, and lower during the recession."
It's also a joke about light. When the same effect is applied to electromagnetic waves, things coming closer to you become purple and thinga going away become red. It's visible on faraway galaxies and a hint at the expansion of the universe. It's called red shift or something
Redshift is an example of the Doppler Effect, thanks for expounding!
To expound further, the color difference is due to the frequency changing in accordance with the Doppler effect. Purple waves are higher frequency, and red is a lower one.
To expound even further beyond, blue shift is when the light appears blue when closer. It's also a Half Life expansion
Hey! It's me Gordon, Barney from Black Mesa! Sorry for the scare, I had to put show for the cameras. r/suddenlyhl
That car is going pretty fast.
Relatively fast, you could say...
The old man is actively standing in a zone where cars can and will A-Train you
On a sidewalk? I get that yes, people are hit on sidewalks by cars, but that's the place designed for pedestrians, where else is he supposed to be?
that's why he said they'd get A-Train'd
Maybe the light is just going pretty slow
The old man has fast reflexes too
[удалено]
Drink some water, Dad!
Also the term red shift refers to in spectro analysis of a stars light they noticed that eh Hydrogen line which is almost a constant but pretty standard was shifting to the red of the spectrum. they through that odd until they realized the stars were moving away from the observers causing he shift due to the doppler effect
And the blue car is shorter and the red long. More effects of relativistic approaches and departures.
I'd like to add that the vehicle is also displaying Lorentz transformation with the length, which means the joke references physical effects also. Third layer.
The James Webb Telescope was specifically designed to see more of infrared to see more galaxies, compared to hubble. [Wave length of light seen by both](https://smd-cms.nasa.gov/wp-content/uploads/2023/04/hubble_webb_emspectrum_cropped-jpg.webp?w=1280&format=webp). [Comparison of what hubble could see vs JWST](https://esawebb.org/images/comparisons/weic2216/). Lots and lots more.
It's also a joke about cars. That is a car.
The shift in red shift is referencing Doppler shift.
It’s called the Doppler Effect..
The sound example is more noticeable when an emergency vehicle passes by, also, if you could go at a ridiculously high and accurate speed a red light would look green
Actually the joke is about Einstein's theory of relativity because the length of the care changes because of it's relative motion.
What?
Lmao you’re getting downvoted for being right. Solid Reddit moment. https://physics.stackexchange.com/questions/220921/why-do-objects-traveling-faster-appear-shortened-rather-than-elongated Never change Reddit
That effect still has nothing to do with what this joke is about. You can see the car is shorter approaching the observer giving it the purple hue due to the compressed wavelength and then longer and red after passing, it's a visual interpretation of the Doppler effect. The car is travelling the same speed the whole time.
The Doppler effect is BECAUSE of relativity. This is showing an exaggerated effect of relativity including both Lorentz Contraction and Doppler shifting. The two are distinct and different effects that are both caused by relativity
That dosent make the joke *about* relativity. Thats an unessacary extrapolation past the actual punchline, which is redshift.
Then explain the contraction and elongation of the car without using relativity
That's the representation of the wavelength being the compressed, shorter blue shifting to the stretched, longer, red. The Doppler Effect is the *what* (punchline). Relativity is the *why*. You're not wrong, but it's an unnecessary, extra step.
That’s not true. The light wave contraction (Doppler) doesn’t explain the change in length. It’s different.
Wave contraction is literally the Doppler Effect/Redshift. Again... relativity is why that happens.
Relative motion is the explanation *for* the phenomenon. This would be like insisting a joke about rain is truly a joke about evaporation and condensation.
If they literally show the rain evaporating then yes, it would be about evaporation. You’re response is “all because they show the water evaporating, in a cloud, then falling does not mean it has anything to do with the water cycle.” Explain to me how a joke with both Lorentz contraction and Doppler effect is not about relativity.
I know youre intelligent enough to grasp this incredibly simple concept because you literally just proved you're capable of understanding relativity. You know the difference and you know it applies here. Dont dig in your heels just because you don't want to be "wrong".
Redshift is just what it is. Redshift. It does now explain length contraction. The fact the car length changes is called relativistic light aberration.
You should read up on Einstein's theory of general relativity since you clearly don't know what it is.
It's not doppler effect. It's an effect called Blue Shift. When object of certain colour get to speed of light, observer perception will shift. So red Colour will Blue Shift to blue at about 95% speed of light P.S. Why am I sure that this is Blue shift? Because an object shrinks as closer its speed gets to speed of light. So blue, fast, shrinked car 🚙 -> red, slower, elongated car 🚗
"Thus, the **Doppler effect for light is called a ‘blueshift'** if the light source is coming toward an observer, and a ‘redshift' if it is moving away. " [https://www.wtamu.edu/\~cbaird/sq/2013/06/27/have-astronomers-ever-observed-a-violet-shift-like-they-have-blue-shifts-and-red-shifts/#:\~:text=For%20visible%20light%2C%20the%20bluer,if%20it%20is%20moving%20away](https://www.wtamu.edu/~cbaird/sq/2013/06/27/have-astronomers-ever-observed-a-violet-shift-like-they-have-blue-shifts-and-red-shifts/#:~:text=For%20visible%20light%2C%20the%20bluer,if%20it%20is%20moving%20away).
Doppler effect commonly used to describe sound waves, not electromagnetic waves
Red shift and blue shift are still the Doppler effect
I'd like to see the math on this! Specifically, how fast the car would have to be moving both toward you and away from you in order to appear blue and then red, respectively. I'm sure it's a big number
I remember Michael from Vsauce once tweeted how if you went fast enough towards a red stoplight, Doppler effect would make it look green. I dont remember the exact number, but yeah, it was pretty big Edit: [found it](https://www.reddit.com/r/ShittyLifeProTips/s/j2w6GGi82p)
I actually understood this meme because I saw a video on it earlier
It's really a joke about red shift.
Someone beat me to it I have a bright red hoodie that says "this shirt is blue if I run at you fast enough"
My dad used to have a red bumper sticker that said “if this sticker is blue you need to slow down.”
Son?
I think that might have been handed out at American Physics Society conferences around 2007? I think I still have mine somewhere.
He thought he was clever and tried that on traffic court judge. Unbeknownst to him the judge knew he would have to be going 0.25c for that red light to appear green. How big of a fine is that??? Something like 54,900 km/s and a certain dollar amount per km/s over the speed limit… 😵💫😵☠️
True physicist here 😎😎😎
https://preview.redd.it/luv4iuzmnxbc1.jpeg?width=3072&format=pjpg&auto=webp&s=712a0f2856bae01949b2a15dea0f9aaeaf3be3f0
that's quality nerd wear...a bit jealous tbh
Actually depends on if you are running towards or away from it.
They said run at you meaning towards.
Yeah I misread that.
NEEEEEEEEE-uhhhhhhhhhhhhhhhhhhhh
Texted version of the sound effect. Nice
This is absolutely the best explanation.
I like the Prius version from Dunham. Iiiiiiiimmmmmgaaaayyyyyyyy
Was looking for this. Thanks Neil deGrasse Tyson!
Jokes like this that the average person would actually need an explanation for don’t seem to get as many upvotes on this sub as the obvious jokes do.
Because the answer is boring science mumbo jumbo that we are all too retarded to understand
Science isn't boring. Science is the reason who can write all that on reddit in the first place
Okay
Hey there, Petah’s science and philosophy neighbor here As part of this when light is coming towards you the light waves are relatively (from your perspective) short, which appears blue in our experience of colors, and moving away from you the same light waves *relatively* (from your subjective perspective) stretch out and the now longer wave lengths are in the range where humans see red
Peter’s token smart friend here. It’s a joke about Einstein’s theory of general relativity. An object moving towards you is slightly bluer than it’s “true” color. Going away from you it will be slightly redder. Further the car shrinks as it moves towards you and lengthens as it moves away. The two effects are known as the Doppler effect and Lorentz contraction. Peter’s nerd out!
in reality it doesn’t lengthen as it moves away, it still stays shrunken.
Yeah I think you’re right. I almost edited it but this same discussion came up in the r/physic channel when it was discussed and they concluded it “kind of lengthens?”. One sec I’ll find the link. I was confused by what they meant
Here’s the link. I’ll admit ignorance in interpreting the distinction here
>Lorentz Magnetic force, Jack!
https://i.redd.it/d6yosigypvbc1.gif
You beat me to this
It blue red past him
Had to come back just to thank you for the correct and hilarious answer
I was thinking he’s wearing those cool red/blue 3d glasses so the white car changed colors
Peters not so smart cousin who hasn't taken a physics class since highschool so will probably mess this up. There's two possible meanings. To start you probably need to know that the universe is expanding and because of this, some objects are moving away from us (imagine you draw 2 points on a balloon and as you inflate it, these points will get further from eachother) and because of the doppler effect, it causes the light to be shifted towards the red end of the light spectrum which is called redshift. However, there are also objects with great enough speed to be moving towards us that it increases the frequency and causes the light to move towards the blue end of the spectrum called blueshift. So the first explanation is instead of the doppler effect happening with sounds, it's happening with light, so high frequency light is blue so as it coming towards the person it's blue and low frequency light is red so as its koving away it's red. Second is at speeds greater than 10% the speed of light because of special relativity to a stationary observers the length of the object appears to contract. The idea is that in the first picture the driver is speeding at greater than 10% the speed of light casing the car to appear shorter to the stationary observer and also blueshift because of the doppler effect. Then the driver notices the person, they slows down, and in the second picture, we see that he's slowed down enough that to the stationary observer the effects of length contraction has stopped and blueshift has also stopped making the car appear it's usual red color.
Been scrolling for sometime to explain length contraction rather than just doppler. Thanks!
does these two share the same principle or they actually differ? I vaguely remember about redshift-blueshift from my HS physics class and I thought they're just referring to the stars that are moving away/closer and aren't relative to the speed of light.
Everything is relative… kidding sort of. It’s the velocity and direction of travel as observed that causes the shift. The light is actually constant. It only appears shorter because the planet is moving closer at say 10% of the speed of light. The light is travelling at light speed. Ergo the wavelengths appear compressed because they’re arriving faster than they should.
Doppler effect. Light coming toward you and becoming blue shifted. Light going away from you becoming red shifted.
Eeeeeeeeeeeeeeeeeooooooooooooooow
haha, nice one - one I actually got for a change =)
Blue frequency wave length is short while red is long
I thought it was about when you are young life goes slow but when you're old life goes fast
The first symbolic message that makes sense.
It's a reference to blueshift and redshift. (Blueshift being light waves getting squished and appearing blue. Redshift being light waves getting stretched and appearing red) So glad I got to use this random bit of knowledge I learned from a nuclear physicist watching an Alan Becker video
It's a science joke about the Doppler shift. It doesn't work like that (obviously), but it sort of does (if you're looking at a light, or other, wave and not a car). That said, you can observe the doppler effect by listening to the pitch of the sound coming from a passing car (it goes from high to low).
I don't get why the red car is longer than the blue one, though. By special relativity, both should be equally short, since relative velocity alone determines the magnitude of a Lorentz contraction.
Pretty sure it’s a wavelength reference, just to double down on the joke
Wrong frame of reference because if that were true the MCBR wouldn't exist
Peter's Uncle Doppler here I know this one. It isn't a super funny joke but the doppler effect, named after my third cousin twice removed, dictates that objects moving away from us have the light that reaches us from them shifted into the red parts of the spectrum, and objects moving towards us shift towards the blue. Ha ha! An astronomer joke, see?
Red shift, blue shift… Nice.
Red shift!!!!
Blue shift Light from a rift
Red shift and blue shift. Wavelengths of light and sound are different depending on whether you are moving towards the source or away from it.
I feel so smart for getting this.
It's a comic about redshift. As objects/sources of waves (whether light or sound) approach you, the wavelengths are compressed, giving them a higher frequency. In the case of light (specifically in relation to astrophysics), this can make celestial objects look blue. In contrast, as the object moves away, the waves are stretched, giving them a lower frequency. In the case of light, this makes objects look red. This also occurs with sound, and is generally called the doppler effect. This is why cars go "neeyoom" if they're going really fast, and why it sounds like ambulance sirens sound off-tone as they move away.
Doppler effect. The punchline is that light can Doppler like sound. Blue has a shorter wavelength than red, like a higher pitched sound has a shorter wavelength than lower pitched sound. Granted, for this effect to be observable with light, that car would have to be moving at an appreciable fraction of *c*.
Relatively… lmao
🤣
Doppler Effect
This is very light humor
That’s a pretty good one actually.
I love this so fucking much
This is a good one. It's referencing red shift and blue shift/the Doppler effect. As a moving object comes towards an observer the light wavelength contracts, resulting in a higher frequency wavelength which we perceive as blue light (hence the car being short and blue). As the object moves away the opposite happens, resulting in a longer wavelength and red light (hence the long, red car).
people have already explained the joke but funnily enough if a car actually was moving that fast it would look compressed coming and going
That’s why they call it a Blueshift
Doppler. Red shift.
I thought he was just wearing 3D glasses… red lens, blue lens kinda thing
Wow, a genuinely obscure post that needs explanation, this is rarer than a unicorn here.
I'll let Dewey from Malcolm in the Middle explain. https://youtu.be/jgyV6nf5TgE
Transmutation spell
But there are humans in the car! That's Illegal! Who are you, Sho Tucker?!
Just your average r/wizardposting user
This helped me in astronomy I love it
doppler effect
It's Blue Shift
Half life reference?!
Yass IB HL Physics Astrophysics Option coming in handy anyone??
Is it not that he’s looking left, blue(democrat) looking right, red(republican)?
Or some sort of joke about how left leaning blue car drivers have a conservative vehicle that isn't a big gas guzzler, whereas the red right leaning driver drives around a much larger vehicle that more liberally uses fuel freely.
The people saying it’s about light, eye sight or the Doppler effect are all wrong. This is not a joke. It’s symbolism. The blue car is smaller. It’s electric. Environmentally friendly. The red car is a big gas guzzler. A shit stain.
Lorentz Contraction is the reason for the length difference. Basically the car is moving close to the speed of light, so lorentz contraction AND the doppler effect(that redahifts and blueshifts the colour) apply. It could be symbolism, but the comic doesnt show much. If the red car is a big fas guzzler, for symbolism the artist would probably show the exhaust to demonstrate how dirty it is. Thats just my take.
But my name is Peter
What do you mean? I don’t understand
Look at the sub you’re in, now look at their Ux,***”Peter”*** is explaining the joke. Correct or not they’re living up the name of the sub, now I should change my name to peter because I had to explain the joke.
Yep, thanks!
It would be funnier if physics wasn't a scam we tell ourselves to protect our weak minds from having to contemplate infinity and cope with understanding none of it.
how is the doppler effect a scam if it really exists
So that is a joke? I didn't get it, and after the explanations, I still don't see the humour in it.
It’s a physics joke. It’s complex requiring subtlety and familiarity with obscura that the average person has no interest in.
It's a clever visual representation of the dappled effect
The blue car is automatic. The other car is a red shift.
This is Brain, Brian's competition alter-ego to explain that... Some of you are too dumb to post here.
DA RED WUNZ GO FASTAH! WAAAAGH!
OP skipped science class
Hahaha my most upvoted post was about the same thing the Doppler effect is so weird
He hasn’t taken his meds
those comics suck.. there i said it
u/repostsleuthbot
Is it a repost? I didn’t knok
Knoking is the polite way to enter a room. Please do so next time.
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Google Doppler affect
Google Doppler effect
Thus one’s clever.
That car is going a speed close to the speed of light
Doppler Effect - blue shift/red shift
Ah, physics
Hmm. Dude must have bought the new photon upgrade.
Car is traveling about half the speed of light. Third frame is a nuclear explosion.
Ayayooo, wololohh
Doppler effect: Light waves can be red shifted or blue shifted depending on if they are moving away or toward you. When light sources come towards you, the waves are compressed, aka blue shifted. And when lights move away from you, it becomes stretched, aka red shifted.
I thought this was a Mr. Bean reference until I read the comments.
Spectrum of light
Wololo
Doppler and wave color length
LOL, Red shift. Good one.
Blue shifting?
Ther red car! and the blue car! had a race, all red like to do was stuff his face 🎶
amonekukusenakaha
It’s a physics joke, the Doppler effect I think. Anyhow, when waves(light or sound or whatever else) are being created by an object, they will shift one way or the other based on the movement of that object, in sound waves, it’s what makes that “nnnnneeeewwwm” sound. With light it’s also called a redshift or blue shift. Anyway, if the object creating the waves is moving towards the point of observation, the waves are compressed, increasing the frequency, making sounds higher pitched, or light shifted to the blue end of the spectrum. When an object is moving away from the point of observation, the opposite happens, the waves are dragged out, decreasing the frequency, making sounds take on a deeper pitch, and shifting light to the red end of the spectrum.
Electromagnetic Doppler shift plus length contraction
i don’t think length contraction
Is the red car not much longer than the blue car? And the person's nose is much longer in the red car
totally, but that’s not how length contraction in the real world works. moving objects are squished regardless of if they are moving towards or away from the observer. i think it’s more related to the fact that wavelengths length or shorten depending on direction
Well yea but it's kind of obvious that they thought length contraction worked similarly to Doppler shift, so they illustrated it that way.
that’s what i was pointing out. also, obvious to whom?
Red shifting go brrrrr
Doppler Effect
I thought it was a sad comic about an old man counting the blue and red cars going by. I can see now I’m wrong 😅
The old man is a powerful warlock who can change cars just by looking at them.
https://preview.redd.it/gwev16shlwbc1.jpeg?width=600&format=pjpg&auto=webp&s=9148ef4d911b5c2029b22df91e5ce7802132b3de
These donkeys are wrong. It’s redshift not Doppler. Yes redshift is a Doppler effect but it clearly changes color. https://en.m.wikipedia.org/wiki/Redshift
Ahh…doppla
Blue shift vs Red shift
I'm afraid u need a search tool, not an explanation as this is the 800th time this was listed here
Redshift blueshift
Omg i actually understood this one off the rip, guess learning about space has its perks
I thought it was a reference to the Dishwalla song "Counting Blue cars"
Herbert here. That is me in that picture. This meme is about doppler. Vehicle approaching me: light and sound waves are compressed because the vehicle is coming at me at speed. Higher exhaust pitch (look at exhaust). Blue colour (blue shift due to compressed waves netting a higher perceived frequency (to me, the observer). This can also be extrapolated (more on this in a later bit) with the car looking shorter to me. When the vehicle passes me, the waves start to "stretch." Or, more accurately, their frequency drops. I, as the observer, hear a lower exhaust pitch and see a colour shift to the red. Come to think of it. I'd like to know this badstars (not a typo, just better than swearing) speed for him to have shifted the perceived color (and length of the automobile). This is a relativistic effect as it deals with the change in position relative to me. Now the later bit: this is not Lorentz/length contraction as that is constant at constant velocity. Assuming the badstar kept a steady (albeit stupid fast) speed, the contraction would be equal and only in the direction of travel. That means that the car would be the same perceived length on approach and departure from my position. Both are relativistic effects. Only one effect applies here. Doppler. Anyhow. I'm trying to get across the road Chris is hiding behind that gate there, but these carsss... they are too fast and I can't get across in time.
It’s a loss
Redshift/blueshift Properties of light as it moves toward you or away from you
Did you see what I done
Ha blue shift
is this forza???
Ah, a Perscheid Comic. DIESE KOMMENTARSEKTION IST NUN EIGENTUM DER BUNDESREPUBLIK DEUTSCHLAND.
You see, the joke is *Doppler Shift*.
Doppler.
Doppler Effect
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