When I was a kid my dad always watched the discovery channel so I watched with him. Till this day I love science especially astronomy. The point is I will watch your videos with my daughter so she can know its okay to like science. I won't force her into it but I want her to see you a successful, happy, woman of science...along with others. Thank you for what you do.
When I read the joke on your credits screen at 8:13 onwards, I thought to myself: 'If we could nominate a queen of puns, I would surely nominate Physics Girl'.
@5:32 For anyone intrigued/fascinated by the geometrical optics effects: also read up on iridescence (what gives soap bubbles, opal gem stones and ammolite fossils their rainbow colors).
Dude I had one prof that actually made everybody come out knowing less. He explained the simplest topics in the most round about ways. He was basically trying to say that in java there is no super class object separate from the child object, they are just the same object, but they search for methods in different locations... which I'm pretty sure nobody thought there was a separate super object, but he thought we did.... so his examples he named all the variables fred1 fred2 and fred3 and confused the shit out of everybody for life (except me because I finally asked him wtf is up with his brain)... if anybody has ever had this prof in their life... theyd recognize him by the fred variables and his catch phrase "its not rocket science people!"...
@@SquirrelASMR When I was 17-18, I had a physics teacher that literally wrote the book, that is the formula compilation book for all subjects from math through chemistry to physics. So there is nooo doubt that he had a sever case of knowledge. Him as a teacher? Well... there is that saying about paint, you know...
Hi Physics Girl. Mr. Pedant here. You said a raindrop was about 1mm in diameter and but in mist or fog, some water droplets are about 1 micrometer, which you pronounced as /my-CHRAHM-eter/. Actually that is the name of the instrument for measuring small lengths. The lengths themselves are call /my-cro-ME-ters/. See the Meriam-Webster Dictionary. In Canada, when we switched to the SI ("metric system"), we standardized the pronunciation of all the names for fractions and multiples of basic units. So we no longer say /ki-LAHM-eter/ for a length (distance), but /kiloh-ME-ter/ to be consistent with milli-, centi- and deci- meter.
It is just how larger water drops fall and the middle flattens out due to the air hitting it as it falls. If the drop is too big, it splits into 2 smaller drops. The headphones shape is halfway from one drop splitting into 2.
I will always remember my college physics professor making us memorize "the index of refraction of light is wavelength dependent" and having to put those words on the exam.
I see circular rainbows all the time when flying (which I do twice a week), small ones near the sun are common, circular ones around the sun I've seen several times, rings around the moon are pretty common, and double or triple rainbows are even more common. Spider web rainbows I have never seen (and I'm okay with that...) and I may have seen white rainbows but assumed the colors were washed out or blocked by clouds or other visibility limiters in the foreground. Yet another cool video!
Funny thing about those halo like things you see from airplanes, is the fact that the center of those is always the eyes of the one seeing them. Taking a picture or video like you did therefore allows one to see where in the airplane you were sitting. With normal cellphone cameras it is often quite hard to get it focused correctly though. Mine are always from the very front of the plane, but then i am sitting on the flightdeck anyway. The most amazing halos i have seen were those around a full moon. Especially if there were two or even three around the moon. And yes, that actually does happen if there is enough humidity in the air (but no clouds).
There's even weird materials /structures with an index of refraction such that waves moves faster than light through it. (light still moves at the speed of light, and so does the wavefront, just the waves go faster)
So cool! I once witnessed a white moon-bow. It was a full moon with no clouds on one side of the valley, with cloud cover and light mist on the other side catching the light. No photo worked cause it was at night, but still one of the most magical moments for me.
When I was a kid I used to create small full circle rainbows with a garden hose, using my thumb to make a fine mist and spraying it at just the right spot.
Hey, i have some feedback! I clicked on the video with the White Rainbow title and thumbnail. I was curious because i didn't know it was even possible. I wouldn't click on this title and thumbnail. (Spider Rainbow) Because i know what a rainbow looks like. You're probably experimenting with it and that's cool. I just thought it would help to hear it like this instead of looking at the numbers. But i really enjoyed the video anyway. Learned some things again! Thank you and keep doing what you're doing.
And that paper. It's a REVIEW paper: 255 references! It pretty much covers the entire field of droplet interactions, a true master-course. When I was a software engineer doing research in sensors and instrumentation, I had the task of developing algorithms to do color correction for a digital video camera that took 100,000 frames per second. The interactions of light on the surface of a semiconductor use math just like that in the above paper. It felt like I was seeing some old friends I've been away from for far too long. Who now speak in a foreign language...
When light goes through a material slower than the speed of light, don't the photons actually still travel at the speed of light? It's just that they get absorbed and re-emitted a bunch and that process takes up some time.
I had that same question, this video from Fermilab explains what's happening more clearly than anything else I found. ruclips.net/video/CUjt36SD3h8/видео.html
Actually she did, but not explicitly. Its just a matter of perspective, when you sit in the plane above the clouds and look opposite direction of the sun. The plane itself doesn't play any role at all (except that it also casts a shadow which you see in th middle of the rainbow, but also a skydiver would see that around his own shadow)
@@simonk5896 Right. I was flying high last summer in a powered para-glider and went above clouds. I could see my wings shadow and my bodies shadow, and the ring rainbow was around my head. The sunlight hitting the clouds was being reflected and refracted back towards the sun. My head was just between them so I could see it.
Refraction: Change in direction of propagation of light as a result of its travelling at different speeds at different mediums. Dispersion: The separation of white light into it's seven constituent colours. (Which happens due to bending) Total Internal Reflection: The complete reflection of a light ray reaching an interface with a less dense medium when the angle of incidence exceeds the critical angle.(Thus the light is coming from a denser medium and when it is incident on the rearer medium it bends) In all the above 3 statements there is this process happening which is BENDING OF LIGHT But when I see the diagrams of all the three they are different, the diagram for Refraction shows only white light bending, the diagram for Dispersion shows white light splitting into 7 colours and the diagram for TIR shows bending of light then dispersion then TIR taking place then bending again and refraction (ALL 3 of them happen) Just like for a rainbow Why doesn't dispersion take place while refraction happens, and when does Refraction take place and when does Dispersion take place?
About the speed of light , i dont think that it changes from one medium to another but the photons absorbed by different materials differently so it appears in different wavelength , love your videos
Back in 2007 I took a photo of the fishing fleet at Alert Bay on Cormorant Island, British Columbia, and when I viewed the photo later there was a clearly visible white rainbow (or fog rainbow as I called it) over the group of fishing boats. Turned out to be a very cool pic!
I saw a rainbow at night once back when I lived in Port St. Lucie, Florida. Not a lot of light pollution there and it was a full moon out when I saw it. It had no color but instead, it had a dark to light greyscale. I looked it up and sure enough, it's a thing. I'm glad I had the opportunity to see it. Truly amazing.
Using a scanner with fragile material protected in Mylar sheets can give you subtle diffraction patterns. Have also seen rainbows along beside riding on the road when crews have been a bit messy cleaning up after repainting with reflective paint :-)
I kinda knew all that except for the angles and the "pilot glory's", never heard of them before. However you made me think of a question that I can't get an answer to, at least no better answer than "atmospheric distortion". Why do stars twinkle different colours, often seemingly cycling through a sequence of colours, and if it is cyclic why is it cyclic? Also, why don't all stars cycle through the same sequence of colours? These questions have bugged me for decades. :P Love all your vids Diana!
In some of the white rainbow photos, you can see they actually form multiple rings! Repeated areas of light and dark like that are very representative of diffraction!
This video is perfect for my son. He’s learning all about wavelengths in science Thai month and this week he is working with visible light. This video will be a great supplement to the curriculum. Thank you Dianna!
This is actually so interesting and you explain this in an easy way to understand. It's gonna be so awesome seeing you with Starset ☺️ also so cool seeing the mask in this video
I used to play around with 3D software and an IOR chart was always helpful when applying materials to objects. Different materials have a different IOR. This was more in depth and interesting. Thanks!
Wonder if Physics Girl has ever covered Scheerer's Phenomenon? Didn't have an explanation for the longest time, and even though I eventually stumbled across the reason, I still find joy in its simple beauty.
I was on a island and walked out on a small peninsula when I saw rain heading my way. I thought about heading for cover until I saw a rainbow had formed and was headed straight for me. I couldn't let this opportunity "pass by" 😉. So I stood there and let the rain soak me and the rainbow pass around and over me. Even though my perspective changed and the rainbow vanished as it got close, I saw a boat in the ocean and imagined they saw the full effect of the rainbow passing over me and wondering if the pot of gold passed by JUST beyond my grasp. No pics as this was before iPhones but I will never forget this once in a lifetime occurrence. Thanks for this video and reminding me of this day.
A similar rainbow to the one on the shadow of airplanes is a rainbow halo around the shadow of your head looking down on a road that has freshly painted stripes! I'm guessing it's because of tiny droplets of the reflective is scattered all over the road's surface. It's super cool but distracting when cycling!
I find it interesting that the differences in the index of refraction based on color/wavelength isn't taught in some physics classes, given how absolutely critical that information is to anything that uses optics, like astronomy, photography, videography, etc.
Partially true but forgot about the secret space mirrors used when the sun dims, you know the mirrors are in place when the sun light looks crystal white. It’s kinda hard to not notice it because it’s soo blinding white, as our sunlights is naturally yellowish white. Oh and also when Stratospheric aerosol injection is in use not only for the purpose of Solar radiation management when mirrors are in place, but for other various programs and projects as well❤️🗝🌀
Yora "intuition" has little to do with biological evolution in the first place - having it the way it is probably does, but the "contents" of your intuition don't - it is (un)intuitive for you just because you're (un)familiar with it. BTW, evolution is not a thing nor can it think - it's a process, it doesn't want or give you anything, nor is trying to achieve something(like "good enough"), it just happens.
Light goes at light speed all the time in every medium. Even if it wants to stop at a drive in it does at light speed. What brings me to an interesting question: Is there any medium, in which something else can move faster than light through it? Love the channel. Learning something new every time.
I once saw a ‘moonbow’ on a stag do. A totally clear night sky on Bodmin Moor, with a full moon and a tiny bit of drizzle. A single, bright, clear bow of white light.
A double rainbow is caused when the light reflects internally twice before refracting, instead of the one internal reflection of a normal rainbow. In principle, there is nothing to stop the light reflecting internally indefinitely, causing many rainbows, though each one is fainter then the one before it. Third and fourth order rainbows are towards the sun, while fifth and sixth order rainbows fill the gap between the first and second order.
2:33 as far as i know violet and red will not travel at different speeds. as they enter media their wavelength and frequency will change accordingly to keep the velocity of the both the colors same. higher the frequency lower the wavelength vice versa, wavelength of red is more than that of violet so its frequency is less. velocity=wavelength*frequency and frequency of light will not change as it changes medium but frequency of monochromatic light will change to keep the velocity constant as the wavelength of the monochromatic light also changes
My favorite rainbow phenomenon would have to be the lunar corona. I see this especially during the winter and I only see it during a full moon. This is what I see when I see a lunar corona: Blue light at the edge of the moon, no red or other colors, just blue Further out, a circular rainbow around the moon Even further out, a faint double rainbow, but this time with the colors in the opposite direction to that of the more prominent rainbow, so if red is on the outward edge of the prominent rainbow, in the faint double rainbow, the red is on the inward edge.
The weirdest thing about rainbows is that the light is being reflected back at you inside the rain drops, not being scattered/refracted/diffracted as it comes towards you. Light is fantastically complicated. Also, not really related at all but Diana saying "micrometer" made me think... English is absurdly inconsistent. We say kilometre and micrometre as one word, but milli metre is split up. Kilo gram too.
I was actually aware of light having different speeds in different mediums, it's what causes chernkov radiation. When something travels ftl in a medium
4:30 This is actually very similar to Brocken effect which has pretty spooky lore around it. It was described by Johann Esaias Silberschlag in 1780 after he saw it on the summit of Brocken in Hertz mountains. Thing is, that instead of a shadow from a plane inside the glory you see shadow of yourself. And because it's not a place where you expect to see a shadow, some people think that it's a spirit/ghost or in some cases Jesus. Spooky part is actually limited to Polish mountains ( started in Tatry mountains around 1930 ) and claims, that if you saw one such thing, you gonna die in the mountains soon. If you manage to spot this phenomenon for a third time however, the bad woowoo mojo mambo jumbo is going to go away. I heard that from a friend and we saw it the day after, made me laugh pretty hard and spooked my friend substancially :)
The index of refraction is one of the reasons why i disbelieve in cosomical idea of gravitional waves planetary distances. As soon as domains change the speed of light. Then all that measurement stuff goes out the window. Its kinda like the butterfly effect.
I’ve got a few pictures I got of one in the middle of the night. I was amazed and happy to have seen one. And tell them I have never seen or heard of one.
Hey Diana! I was at sea once at night with a full moon behind us, and ahead of us was a rainstorm - the moon created a rainbow ahead just like the sun might have during daytime - it was mostly white, but we could make out subtle red on the outer edge, and violet on the inner edge, just like daytime rainbows. It never occurred to me that this could happen! It was stunning, and it’ll be burned into my brain forever. Sorry I don’t have a picture to share though 🌈. Loved your video as usual :)
I see rainbows often in the office - one of the conference rooms with glass walls refracts light and casts a long rainbow on the floor that also reflects on other glass walls.
The ether medium has the same properties as air does. So while sound diffracting around an object causes dispersion of the frequencies, so too does light diffracting around an object. Refraction is just sound or light diffracting around multiple objects, then arriving at a distant location through all of those obstacles, we know that as an atmosphere to light. A continuum spectrum from a pulsar at 200 LY, does the same thing thru the Inter-Steller Medium, the red end of the spectrum arrives about 1/2 sec ahead of the Gamma end. Dispersion is also seen from supernova and Fast Radio Bursts, all due to the fluid nature of the ether medium. The other thing the affects refractive index, as well as affecting the speed of light through an atmosphere, is the magnetic flux density of an atmosphere, such as in a glass lens. The Earth actually refracts light, at sunrise, over 1000 times as much as the Sun's atmosphere refracts light.
So, if the droplets can be within the range of the wavelength of light, then that means they can block and reflect certain wavelengths but not others. This would cause those colours to be filtered out, altering the perceived colour. I suspect this is only a small part of it, as a rainbow would require droplets of a relatively wide range of sizes
Many years ago I was on an airplane passing over Desert Regions of the west (USA) maybe Nevada, I dont know. Anyway, upon looking down and out of the window I saw a large white ring on the ground. I was only able at the time to conclude (by assumption) that what I was seeing was more like the effect of a reflective sign material. Could have been glass beads in the sand or something similar. It was, at the time strange and puzzling. Thank you for helping me understand that the answer to everything, once again, is 42. (Sigh of relief) 😎
1:50 it is really should not be a surprise. There was an interesting research on stopping the light with special crystals (thing to google - stop light physics)
There probably isn't a "right" way to pronounce micrometre, but generally I feel like when I hear someone use a short "o" (like kilometre, especially with slightly more emphasis on the "o") I think of a the measuring device (helpfully distinguished in British spelling as a micrometer); and when they use a long "o" (like nanometre) I think of the unit of distance. I wonder if that's why we use the term "micron"...
Pilot glories: I am a retired airline pilot - and a former hang glider pilot. The "pilot glories" I have observed for almost 50 years are not so much about a rainbow forming around the shadow of a flying aircraft as the fact that the light is more intense immediately around the shadow itself than the surrounding area. My personal theory was that since any heavier-than-air aircraft stays aloft by forcing a considerable amount of air downwards when passing through it, the momentary pressure differential in the air caused the air to act like a weak lens, concentrating the light around any shadow formed by an aircraft. This phenomenon is easily seen when a shadow is observed on clouds, snow or even water and the ground. What I always found very interesting is the fact that this effect is very similar whether you are observing the brightness around the shadow formed by a 200 ton jet you are flying in at 500 knots or a 400kg ultralight at 80 knots. I have even observed this phenomenon when flying a hang glider - total weight a mere 120kg and very low speed! For some reason the speed or weight of the aircraft does not appear to be a determining factor... Riddle me this, Physics Girl!
OMG! I really love your videos! The way you present all kinds phenomena is so enthusiastic, that makes me wanna go out learning everything about physics! Well done! Keep up!
When I was a kid my dad always watched the discovery channel so I watched with him. Till this day I love science especially astronomy. The point is I will watch your videos with my daughter so she can know its okay to like science. I won't force her into it but I want her to see you a successful, happy, woman of science...along with others. Thank you for what you do.
aww
Legend. Keep it up. I wanna be doing the same soon!
There are plenty pf bright women in physics and astronomy.
@@jjeherrera that's why I said "others". I was just thinking that this video is also something that she can get started with. its rainbows...😁
Last summer caught a double rainbow ! Under my username.
(reads title)
Me: Oh my god Diana, you can't just ask rainbows why they're white.
Typical Physicists....🤣🤣
She changed the title!
@@dereksmalls6238 NOOO, my movie reference no longer works =(
@@facelesshalo5174 I feel for you, I really do.
I WANT MY PINK SHIRT BACK! I WANT MY PINK SHIRT BACK!!
When I read the joke on your credits screen at 8:13 onwards, I thought to myself: 'If we could nominate a queen of puns, I would surely nominate Physics Girl'.
I almost missed it ! Thank you for making me notice
And Simone Giertz
@@arantes6 you're most welcome, arantes6 😊
Physics Girl:"Maybe you knew. Now you do."
Notorious BIG: "If you don't know. Now you know."
Notorious PHY?
@@falxonPSN Notorious DNA
I bet she didn’t know that until just now. She likes metal, rock
So part of Biggie's soul lives on in Dianna.
@@falxonPSN PHYS*
@5:32 For anyone intrigued/fascinated by the geometrical optics effects: also read up on iridescence (what gives soap bubbles, opal gem stones and ammolite fossils their rainbow colors).
And humming birds too..
short and simple: your videos bring me happiness
I've learned more from Physics Girl than my college professor that simply gave us homework without bothering to teach us.
Haven’t we all
lol
Dude I had one prof that actually made everybody come out knowing less. He explained the simplest topics in the most round about ways. He was basically trying to say that in java there is no super class object separate from the child object, they are just the same object, but they search for methods in different locations... which I'm pretty sure nobody thought there was a separate super object, but he thought we did.... so his examples he named all the variables fred1 fred2 and fred3 and confused the shit out of everybody for life (except me because I finally asked him wtf is up with his brain)... if anybody has ever had this prof in their life... theyd recognize him by the fred variables and his catch phrase "its not rocket science people!"...
Then your professor must suck or doesn't take his job seriously.
@@SquirrelASMR When I was 17-18, I had a physics teacher that literally wrote the book, that is the formula compilation book for all subjects from math through chemistry to physics. So there is nooo doubt that he had a sever case of knowledge.
Him as a teacher? Well... there is that saying about paint, you know...
And knowing the explanation only adds to their beauty.
Hi Physics Girl. Mr. Pedant here. You said a raindrop was about 1mm in diameter and but in mist or fog, some water droplets are about 1 micrometer, which you pronounced as /my-CHRAHM-eter/. Actually that is the name of the instrument for measuring small lengths. The lengths themselves are call /my-cro-ME-ters/. See the Meriam-Webster Dictionary. In Canada, when we switched to the SI ("metric system"), we standardized the pronunciation of all the names for fractions and multiples of basic units. So we no longer say /ki-LAHM-eter/ for a length (distance), but /kiloh-ME-ter/ to be consistent with milli-, centi- and deci- meter.
"rainbowy edition"
That's why we love physicsgirl
Assume the W̶a̶t̶e̶r̶ ̶d̶r̶o̶p̶l̶e̶t̶ [cow] is a perfect sphere
Fun fact: if the sun were to be replaced by Sirius, we'd have violet sky.
Fun fact: we'd all be dead.
Siriusly?
We would have Sirius issues.
Don't ask about Uranus...
@@MitzvosGolem1 Respectable dad joke.
fun fact: the sun is green.
@@Kiwi_Ladd I am a grandpa now little girl born two months ago!!!!!!:-)
waitwaitwaitwait. wait! "catastrophy theory"? water drops look like headphones?! MAKE A VIDEO ABOUT *THAT*!
It is just how larger water drops fall and the middle flattens out due to the air hitting it as it falls. If the drop is too big, it splits into 2 smaller drops. The headphones shape is halfway from one drop splitting into 2.
@EveryDay Yep, it is showing the air hitting the bottom and almost breaking through the middle when it breaks into smaller drops.
But light does travel at speed of light in a material, it just travels longer path because it is bouncing from atom to atom.
I will always remember my college physics professor making us memorize "the index of refraction of light is wavelength dependent" and having to put those words on the exam.
Well you still remember that so his methods worked lol
It only worked if it made you understand.
I see circular rainbows all the time when flying (which I do twice a week), small ones near the sun are common, circular ones around the sun I've seen several times, rings around the moon are pretty common, and double or triple rainbows are even more common. Spider web rainbows I have never seen (and I'm okay with that...) and I may have seen white rainbows but assumed the colors were washed out or blocked by clouds or other visibility limiters in the foreground. Yet another cool video!
Funny thing about those halo like things you see from airplanes, is the fact that the center of those is always the eyes of the one seeing them. Taking a picture or video like you did therefore allows one to see where in the airplane you were sitting. With normal cellphone cameras it is often quite hard to get it focused correctly though.
Mine are always from the very front of the plane, but then i am sitting on the flightdeck anyway.
The most amazing halos i have seen were those around a full moon. Especially if there were two or even three around the moon. And yes, that actually does happen if there is enough humidity in the air (but no clouds).
Oh, dear. They’re the farts of unicorns. I thought everyone knew that.
Vortex farts, that's why they are circular.
There's even weird materials /structures with an index of refraction such that waves moves faster than light through it. (light still moves at the speed of light, and so does the wavefront, just the waves go faster)
So cool! I once witnessed a white moon-bow. It was a full moon with no clouds on one side of the valley, with cloud cover and light mist on the other side catching the light. No photo worked cause it was at night, but still one of the most magical moments for me.
When I was a kid I used to create small full circle rainbows with a garden hose, using my thumb to make a fine mist and spraying it at just the right spot.
Hey, i have some feedback!
I clicked on the video with the White Rainbow title and thumbnail. I was curious because i didn't know it was even possible.
I wouldn't click on this title and thumbnail. (Spider Rainbow) Because i know what a rainbow looks like. You're probably experimenting with it and that's cool. I just thought it would help to hear it like this instead of looking at the numbers. But i really enjoyed the video anyway. Learned some things again! Thank you and keep doing what you're doing.
Wow, for sure my physics class in both high school and uni left out that bit about light refracting different by wavelength. TIL. Thanks!
And that paper. It's a REVIEW paper: 255 references! It pretty much covers the entire field of droplet interactions, a true master-course.
When I was a software engineer doing research in sensors and instrumentation, I had the task of developing algorithms to do color correction for a digital video camera that took 100,000 frames per second. The interactions of light on the surface of a semiconductor use math just like that in the above paper. It felt like I was seeing some old friends I've been away from for far too long. Who now speak in a foreign language...
wow that Alexandru photo is gorgeous
*_instead of a pot of gold_* what would be at the end of a white rainbow?
When light goes through a material slower than the speed of light, don't the photons actually still travel at the speed of light? It's just that they get absorbed and re-emitted a bunch and that process takes up some time.
i was thinking that the light just takes a longer path through materials and not a straight line??????
I had that same question, this video from Fermilab explains what's happening more clearly than anything else I found. ruclips.net/video/CUjt36SD3h8/видео.html
The sources mentioned in the description are AMAZING & very insightful! Optics is a beautiful!
perfect timing for such a video :D
Was just messing around with refraction and reflection functions
as well as with fresnel :D
"Why Do These Strange Rainbows Form Around Planes?"
Proceeds to not explain why these strange rainbows form around planes
Right? There are so many other titles she could have used. Just clickbait.
Actually she did, but not explicitly. Its just a matter of perspective, when you sit in the plane above the clouds and look opposite direction of the sun. The plane itself doesn't play any role at all (except that it also casts a shadow which you see in th middle of the rainbow, but also a skydiver would see that around his own shadow)
@@simonk5896 Right. I was flying high last summer in a powered para-glider and went above clouds. I could see my wings shadow and my bodies shadow, and the ring rainbow was around my head. The sunlight hitting the clouds was being reflected and refracted back towards the sun. My head was just between them so I could see it.
technically, light always travels at the same speed, but in materials, light bounces off the particles "slowing" it down.
Zachary Peterson
Very Wrong!
It's electromagnetic wave interactions. No "bouncing".
@@makeracistsafraidagain then what are the "interactions", light has both properties of a wave and a particle, it bounces off of things
1:50 lol that's badass.
The last time I was this early, the cosmos was still forming...
And, Physicsgirl was explaining that.
The cosmos is still forming and never stopped. 🌌
Very few women like to be reminded of their age, you know.
Light does go at the same speed in a vacuum and through materials, just the path followed isn't the same.
Refraction: Change in direction of propagation of light as a result of its travelling at different speeds at different mediums.
Dispersion: The separation of white light into it's seven constituent colours. (Which happens due to bending)
Total Internal Reflection: The complete reflection of a light ray reaching an interface with a less dense medium when the angle of incidence exceeds the critical angle.(Thus the light is coming from a denser medium and when it is incident on the rearer medium it bends)
In all the above 3 statements there is this process happening which is BENDING OF LIGHT
But when I see the diagrams of all the three they are different, the diagram for Refraction shows only white light bending,
the diagram for Dispersion shows white light splitting into 7 colours and the diagram for TIR shows bending of light then dispersion then TIR taking place then bending again and refraction (ALL 3 of them happen) Just like for a rainbow
Why doesn't dispersion take place while refraction happens, and when does Refraction take place and when does Dispersion take place?
About the speed of light , i dont think that it changes from one medium to another but the photons absorbed by different materials differently so it appears in different wavelength , love your videos
Back in 2007 I took a photo of the fishing fleet at Alert Bay on Cormorant Island, British Columbia, and when I viewed the photo later there was a clearly visible white rainbow (or fog rainbow as I called it) over the group of fishing boats. Turned out to be a very cool pic!
I saw a rainbow at night once back when I lived in Port St. Lucie, Florida. Not a lot of light pollution there and it was a full moon out when I saw it. It had no color but instead, it had a dark to light greyscale. I looked it up and sure enough, it's a thing. I'm glad I had the opportunity to see it. Truly amazing.
The markers were a nice touch! @PhysicsGirl
Using a scanner with fragile material protected in Mylar sheets can give you subtle diffraction patterns. Have also seen rainbows along beside riding on the road when crews have been a bit messy cleaning up after repainting with reflective paint :-)
@2:42 Yes! That _is_ very interesting. I had never heard an explanation of WHY white light splits into a rainbow.
This is really amazing!! Nature has some crazy stuff and it's wonderful to see them explained, thank you for your content :))
I kinda knew all that except for the angles and the "pilot glory's", never heard of them before.
However you made me think of a question that I can't get an answer to, at least no better answer than "atmospheric distortion". Why do stars twinkle different colours, often seemingly cycling through a sequence of colours, and if it is cyclic why is it cyclic? Also, why don't all stars cycle through the same sequence of colours? These questions have bugged me for decades. :P
Love all your vids Diana!
In some of the white rainbow photos, you can see they actually form multiple rings! Repeated areas of light and dark like that are very representative of diffraction!
This video is perfect for my son. He’s learning all about wavelengths in science Thai month and this week he is working with visible light. This video will be a great supplement to the curriculum. Thank you Dianna!
Loved that your first rainbow pic was from Phil Plait.
This is actually so interesting and you explain this in an easy way to understand. It's gonna be so awesome seeing you with Starset ☺️
also so cool seeing the mask in this video
I used to play around with 3D software and an IOR chart was always helpful when applying materials to objects. Different materials have a different IOR. This was more in depth and interesting. Thanks!
Wonder if Physics Girl has ever covered Scheerer's Phenomenon? Didn't have an explanation for the longest time, and even though I eventually stumbled across the reason, I still find joy in its simple beauty.
Thanks @Physics Girl/Dianna you inspire me to question and experience the world around me in new ways. Science excites me
loved seeing this pop up on my feed, i was just reading up on sundogs yesterday!
Thank you so much for this Dianna! I've seen glories a few times, took photos and mad videos for searching afterwards but kept forgetting. Now I know!
I was on a island and walked out on a small peninsula when I saw rain heading my way. I thought about heading for cover until I saw a rainbow had formed and was headed straight for me. I couldn't let this opportunity "pass by" 😉. So I stood there and let the rain soak me and the rainbow pass around and over me. Even though my perspective changed and the rainbow vanished as it got close, I saw a boat in the ocean and imagined they saw the full effect of the rainbow passing over me and wondering if the pot of gold passed by JUST beyond my grasp. No pics as this was before iPhones but I will never forget this once in a lifetime occurrence. Thanks for this video and reminding me of this day.
I was watching this with my nephew and the moment you said refraction he was like nope I'm out I didn't come here to learn math
You need to foster an appreciation in him of both math and the sciences - at least enough that he recognizes the difference.
Some will never learn... pity.
A similar rainbow to the one on the shadow of airplanes is a rainbow halo around the shadow of your head looking down on a road that has freshly painted stripes! I'm guessing it's because of tiny droplets of the reflective is scattered all over the road's surface. It's super cool but distracting when cycling!
I find it interesting that the differences in the index of refraction based on color/wavelength isn't taught in some physics classes, given how absolutely critical that information is to anything that uses optics, like astronomy, photography, videography, etc.
Partially true but forgot about the secret space mirrors used when the sun dims, you know the mirrors are in place when the sun light looks crystal white. It’s kinda hard to not notice it because it’s soo blinding white, as our sunlights is naturally yellowish white.
Oh and also when Stratospheric aerosol injection is in use not only for the purpose of Solar radiation management when mirrors are in place, but for other various programs and projects as well❤️🗝🌀
"Maybe you knew. Now you do." That basically sums up most of the video. I knew somethings about rainbows, but not *that* much. Now I do. Thanks.
It's great to hear this explanation. I particularly like moonbows.
"Nature is crazy."
Nature is _counterintuitive._
Your intuition is counternatural
@Canol Onar that's why quantum mechanics is so counterintuitive, but it works every time.
@@tinldw Brains are not intelligently designed. Evolution gave us "eh, good enough".
Martiddy - Sama just because you know nothing about modern theoretical QM frameworks doesn't mean that it "works every time"
Yora "intuition" has little to do with biological evolution in the first place - having it the way it is probably does, but the "contents" of your intuition don't - it is (un)intuitive for you just because you're (un)familiar with it.
BTW, evolution is not a thing nor can it think - it's a process, it doesn't want or give you anything, nor is trying to achieve something(like "good enough"), it just happens.
Light goes at light speed all the time in every medium. Even if it wants to stop at a drive in it does at light speed.
What brings me to an interesting question: Is there any medium, in which something else can move faster than light through it?
Love the channel. Learning something new every time.
I once saw a ‘moonbow’ on a stag do. A totally clear night sky on Bodmin Moor, with a full moon and a tiny bit of drizzle. A single, bright, clear bow of white light.
Ive seen one of the circle rainbows around the moon once and it was genuinely one of the coolest things ive ever seen :)
This is very illustrative. You get some similar phenomena, such as the gloria effect in some nuclear reactions.
Great video topic. Thank you, PG!! Is "rainbow gem" the actual name for what I call "sun stripes?" The sky....never the same show twice.
“Light Pillars” are fun phenomena too!
A double rainbow is caused when the light reflects internally twice before refracting, instead of the one internal reflection of a normal rainbow. In principle, there is nothing to stop the light reflecting internally indefinitely, causing many rainbows, though each one is fainter then the one before it. Third and fourth order rainbows are towards the sun, while fifth and sixth order rainbows fill the gap between the first and second order.
Refracting, defracting or just reflecting. You bring a rainbow to my day, Physics Girl:-)
I always wanted to know what this glory rainbow seen from a plane is! Thank you for the video :)
2:33 as far as i know violet and red will not travel at different speeds. as they enter media their wavelength and frequency will change accordingly to keep the velocity of the both the colors same. higher the frequency lower the wavelength vice versa, wavelength of red is more than that of violet so its frequency is less. velocity=wavelength*frequency and frequency of light will not change as it changes medium but frequency of monochromatic light will change to keep the velocity constant as the wavelength of the monochromatic light also changes
My favorite rainbow phenomenon would have to be the lunar corona. I see this especially during the winter and I only see it during a full moon.
This is what I see when I see a lunar corona:
Blue light at the edge of the moon, no red or other colors, just blue
Further out, a circular rainbow around the moon
Even further out, a faint double rainbow, but this time with the colors in the opposite direction to that of the more prominent rainbow, so if red is on the outward edge of the prominent rainbow, in the faint double rainbow, the red is on the inward edge.
This is how physics classes should be conducted, and they often are by enthusiastic physics teachers. Keep it up
Even after finding out why and how these things happen, it doesn't make them any less glorious.
The weirdest thing about rainbows is that the light is being reflected back at you inside the rain drops, not being scattered/refracted/diffracted as it comes towards you. Light is fantastically complicated. Also, not really related at all but Diana saying "micrometer" made me think... English is absurdly inconsistent. We say kilometre and micrometre as one word, but milli metre is split up. Kilo gram too.
I was actually aware of light having different speeds in different mediums, it's what causes chernkov radiation. When something travels ftl in a medium
42: The answer to life, the universe and everything... and rainbows!
But what is the question?
Love your presentation style!
There is one more type you could cover. Moonbows. These are very specific in condition and location which makes them rarer, but just as amazing.
4:30 This is actually very similar to Brocken effect which has pretty spooky lore around it. It was described by Johann Esaias Silberschlag in 1780 after he saw it on the summit of Brocken in Hertz mountains. Thing is, that instead of a shadow from a plane inside the glory you see shadow of yourself. And because it's not a place where you expect to see a shadow, some people think that it's a spirit/ghost or in some cases Jesus. Spooky part is actually limited to Polish mountains ( started in Tatry mountains around 1930 ) and claims, that if you saw one such thing, you gonna die in the mountains soon. If you manage to spot this phenomenon for a third time however, the bad woowoo mojo mambo jumbo is going to go away. I heard that from a friend and we saw it the day after, made me laugh pretty hard and spooked my friend substancially :)
a delightful explanation of a beautiful range of phenomena
Thanks ! Great info, going to share with my coworkers who were asking about sun dogs.
The index of refraction is one of the reasons why i disbelieve in cosomical idea of gravitional waves planetary distances. As soon as domains change the speed of light. Then all that measurement stuff goes out the window. Its kinda like the butterfly effect.
I’ve got a few pictures I got of one in the middle of the night. I was amazed and happy to have seen one. And tell them I have never seen or heard of one.
Hey Diana! I was at sea once at night with a full moon behind us, and ahead of us was a rainstorm - the moon created a rainbow ahead just like the sun might have during daytime - it was mostly white, but we could make out subtle red on the outer edge, and violet on the inner edge, just like daytime rainbows. It never occurred to me that this could happen! It was stunning, and it’ll be burned into my brain forever. Sorry I don’t have a picture to share though 🌈. Loved your video as usual :)
Whoa. I would love to see a picture of that. What would you think it wound be called?
It sarched it up and it's called a moonbow. I still want to see pictures though.
I see rainbows often in the office - one of the conference rooms with glass walls refracts light and casts a long rainbow on the floor that also reflects on other glass walls.
" 42 " Degrees.!! The Answer to everything, Reference from "The Hitchhikers Guide To The Galaxy"
What a fun video! Thanks Diana! I'm headed to your home state in a week! Maybe I'll see some incredible rainbow phenomena there!
The ether medium has the same properties as air does. So while sound diffracting around an object causes dispersion of the frequencies, so too does light diffracting around an object. Refraction is just sound or light diffracting around multiple objects, then arriving at a distant location through all of those obstacles, we know that as an atmosphere to light.
A continuum spectrum from a pulsar at 200 LY, does the same thing thru the Inter-Steller Medium, the red end of the spectrum arrives about 1/2 sec ahead of the Gamma end. Dispersion is also seen from supernova and Fast Radio Bursts, all due to the fluid nature of the ether medium. The other thing the affects refractive index, as well as affecting the speed of light through an atmosphere, is the magnetic flux density of an atmosphere, such as in a glass lens.
The Earth actually refracts light, at sunrise, over 1000 times as much as the Sun's atmosphere refracts light.
I did an experiment, bending light around a paper staple. The red light bent up to 30 degrees either side of the aiming point, I've got photos.
You should do a video on a Parhelic Circle! We witnessed one and it goes right along with this lesson!
So, if the droplets can be within the range of the wavelength of light, then that means they can block and reflect certain wavelengths but not others. This would cause those colours to be filtered out, altering the perceived colour. I suspect this is only a small part of it, as a rainbow would require droplets of a relatively wide range of sizes
Many years ago I was on an airplane passing over Desert Regions of the west (USA) maybe Nevada, I dont know. Anyway, upon looking down and out of the window I saw a large white ring on the ground. I was only able at the time to conclude (by assumption) that what I was seeing was more like the effect of a reflective sign material. Could have been glass beads in the sand or something similar. It was, at the time strange and puzzling. Thank you for helping me understand that the answer to everything, once again, is 42.
(Sigh of relief) 😎
1:50 it is really should not be a surprise. There was an interesting research on stopping the light with special crystals (thing to google - stop light physics)
There probably isn't a "right" way to pronounce micrometre, but generally I feel like when I hear someone use a short "o" (like kilometre, especially with slightly more emphasis on the "o") I think of a the measuring device (helpfully distinguished in British spelling as a micrometer); and when they use a long "o" (like nanometre) I think of the unit of distance. I wonder if that's why we use the term "micron"...
Pilot glories: I am a retired airline pilot - and a former hang glider pilot. The "pilot glories" I have observed for almost 50 years are not so much about a rainbow forming around the shadow of a flying aircraft as the fact that the light is more intense immediately around the shadow itself than the surrounding area. My personal theory was that since any heavier-than-air aircraft stays aloft by forcing a considerable amount of air downwards when passing through it, the momentary pressure differential in the air caused the air to act like a weak lens, concentrating the light around any shadow formed by an aircraft. This phenomenon is easily seen when a shadow is observed on clouds, snow or even water and the ground. What I always found very interesting is the fact that this effect is very similar whether you are observing the brightness around the shadow formed by a 200 ton jet you are flying in at 500 knots or a 400kg ultralight at 80 knots. I have even observed this phenomenon when flying a hang glider - total weight a mere 120kg and very low speed! For some reason the speed or weight of the aircraft does not appear to be a determining factor...
Riddle me this, Physics Girl!
All the types of rainbows are great, well created.
What about the ring/rainbow-thing around the moon when it's really cold? Something similar?
OMG! I really love your videos! The way you present all kinds phenomena is so enthusiastic, that makes me wanna go out learning everything about physics! Well done! Keep up!
Physics is love🤩❤️
Diana probably sees a lot of rainbows because she's a ray of sunshine.