I pity the fool who goes to school near death valley. 50 years old - still waiting to get their 2 grade science grade. They can't complete their raindrop lab.
@@DackxJaniels That might be actually why this simple experiment is almost never done in schools (It is somewhat likely that someone had tried it in a school setting.) The experiment is very weather depended so you need to prepare it for one of those rainy days. And I think having that prep work and then the experiment on standby is a bit more of a hassle then in worth. Though of course there plenty of places in the world that get rain pretty regular so it might be something worth doing then.
Fraser Steen Experiments might be interesting but they are not that efficient tools for learning. But they might spark interst. However, they interfere routine, which is the most important oart of learning.
I'm a Naval Architect. I've always been told at uni that the two resistances ships have to overcome are friction resistance and wave-induced resistance. Once or twice been told that wave-induced resistance was different from friction resistance because of surface tension... But never quite understood why and that's something this video addresses perfectly. Hydrogen bonds cause water molecules to stay together, and that gives rise to this potential energy on the very surface (or the boundary layer between two fluids, in this case, water and air). This channel is just one marvellous thing for all of the curious people who love science and don't really have someone to learn from or talk to about it. Froude was right and didn't even know why! PS: now friction resistance which encompasses tons of different resistances like pressure resistance, viscous resistance, viscous pressure resistance, etc is a whole world apart... *As Sir Horace Lamb would put it: **_I am an old man now, and when I die and go to heaven, there are two matters on which I hope for enlightenment. One is quantum electrodynamics and the other is the turbulent motion of fluids. About the former, I am really rather optimistic._*
@pjd412 Shouldn't low aerodynamic drag be a much flatter shape, shard-like? I don't think I can agree: practical aerodynamics is a very ancient subject manifesting in spears and arrows for example, which do not look at all like the stereotypical drop shape.
Seems i am watching this channel for quite so time now. For the first time I notice the professor is turning old! I hope he stays well for a long time. I always love listening to his explanations. It makes it look so easy (until you do the math).
Hi Brady, I would love to see some follow up videos with the professors. It could be interesting to hear how developments such as gravitational wave astronomy and just the passage of time may have modified previous statements / answers to your questions.
I feel like rain drops in summer that go along with thunderstorms are much bigger than a few millimeters. Rain seems really diverse from my perspective at least, where you can either have a very tiny spray or very big blobs...
That was FASCINATING! I NEVER would have guessed that when raindrops get too big they basically explode from the "rising" air flow!! That's soooooo COOL!!! -First time I watch a video = LIKED! -First time I liked a video = SUBSCRIBED!! I just CANNOT WAIT to explore the rest of your videos!!! Wo0T-W0oT!!
Actually rain can form in a different way. The kind of rain that Mike described, where vapor is condensing on little particles, forming small drops, and those can bump into each other forming bigger drops (coalescence), takes many hours or even days to develop any rain. That is the sort of rainy day stuff, where a large cloud deck (stratus) is formed in a weather front for example. When you get a shower from a smaller cloud (cumulus) or a thunderstorm (cumulonimbus), rain develops in a different way. Water vapor condenses into tiny droplets at the base of the cloud and move to higher in the cloud due to convective motion. The temperature drops with the altitude and below about 12 degrees Celsius, ice crystals start forming. Water vapor (100% relative humidity) sublimates on the ice crystals, creating snow. As the ice crystals grow, the relative humidity drops, and therefore the water droplets evaporate and so the humidity stays high. The liquid water droplets "feed" the vapor that then sublimates into ice. When the ice crystals grow big enough they start to fall and get in warmer air at lower altitude where they melt into raindrops. Also on their way down they encounter a lot of droplets so they grow bigger due to coalescence. This process is way quicker and is the reason that a thunderstorm can develop rain in (much) less than an hour.
You forgot to mention if the common visual image of a raindrop is real or not. I am left to assume that raindrops are spheres and never go into that well down drop shape. I imagine a drop shape comes from when a portion leaves a larger portion and some adhesion occurs so a bit is drawn off slower and the sphere elongates. But does this mean water drops should always end up spherical?
The "common" raindrop shape most likely comes from seeing something drip. Just before a drop falls from something wet, it looks "drop shaped". After that you would need special equipment to see the real shape.
They are actually flattish at the bottom once they start falling, due to effects of the wind. There's some vids around. Funny thing I see it with my naked eyes living in a 30 story apt in the middle of the building. During a storm, the air that hits the building where I am has nowhere to go but up (as seen when I open the balcony door, and one to the hallway heh). So often the wind speed upwards = the falling speed and I get rain drops floating around the balcony almost perfectly suspended in air. In snowstorms it's often I see nothing but upwards snow if there's a north wind.
That was fun, thanks. Enjoyed the discussion of the early experiments. But there was some fascinating physics left out, such as how rain drops could collect/merge with other drops as it falls...depends on size (effective cross-section radius) of falling drop and target drop. What would be really cool is to discuss how ice crystals form and grow in cold clouds to generate snow. Much different process than the collision/coalescence process he described. I always enjoy the atmospheric phenomena discussions in Sixty Symbols!
Nice video. I worked on this topic long time ago; the Marshall-Palmer size distribution is out of time, because of the behaviour of the diagram near to zero. Many other size-distributions came out, I remember the beautiful papers of Ulrich, and many other physicists, in the 80' and 90's. Some multiparameter Gamma-distributions were born, which more or less adapted their shape to experimental data. But the big question which came from the Marshall-Palmer work, was: what's the relationship between Rainfall rate and the size of drops?
Nice video, but what has to be mentioned as I think, is, that without hail there would be no rain. Coalescing clouddrops can only form very tiny droplets. Bigger raindrops were frozen before, and when they melt, they become raindrops. That's where all those interresting phenomena occur. - And sometimes the hailstone has no time to melt before hitting the ground. The story of raindrops is very interresting indeed, and full of wonders (one of which is the rainbow of course).
I'm in Southwest Florida, USA and one thing I've noticed about storms is that the initial rain that falls is much bigger in size than the actual storm. It's not very intense with the big droplets, but it seems the individual droplets are bigger at the start of the storm the the main part of the storm.
there are down-drafts at the edge of a thunderstorm. when the surrounding air is moving along with the drop, the air resistance is lower, so drops can grow bigger.
i always wondered about the speed at which your car is travelling and the number of drops/amount of water which hits your windshield in the rain. I imagine there are difference in stopped , slow, faster relative to the speed of the falling rain, very fast when aerodynamics become significant, size/amount/speed of rain etc etc, some rich discussion there maybe.
Perfect timing for me; was re-watching the third matrix movie last night and couldn't help myself cringing a little at one of the final scenes where there's a slow-motion CGI shot of Neo's fist going through the rain, hitting Smith in the face, where the falling rain drops are shaped like long rods.. Of course by the movies own logic that can be explained by the matrix glitching out and losing som of the calculations that deal with surface tension and air resistance, but as far as realism goes it looked kind of comically bad to my now-older eyes :p
Seems like at least some of the shrapnel drops could be re-lifted to the upper deck of the cloud via updrafts... or is that really a niche phenomenon? I recall hearing that hail is formed when a storm has these strong updrafts that keep throwing a raindrop to the top of the cloud, where it freezes, then falls and wets again, to be re-lifted to re-freeze. This is how hail chunks the size of robin eggs or bigger are formed... or so I was told.
So what would happen if you'd simulate rain in a big vacuum chamber? If there's no air resistance will the drops of water be larger, would they not balloon up?
Some of the water in a cloud is in liquid form, that's why we see them, so I'm curious as to what causes the water to start to fall out as rain? Clouds can pass over a large region before they start to condense as rain, is it just the cloud getting dirty from some saturated amount of "seeds"?
It basically has to do with surface tension. The liquid water you mention is attached to small dust particles. As the liquid water further condenses, the surface tension keeping it held around the dust breaks and causes it to fall to earth.
I guess there being wind would change things a bit. Also the atmospheric pressure. Like hail that forms in an upwards current until the wind can't hold it in the air anymore and then it falls down. Would a less dense atmosphere, or a lesser gravity, imply larger raindrops, or even streams of water?
I would imagine that the downdraft that often occurs at a storm front might prevent the large drops from experiencing a ballooning effect, hence large heavy raindrops?
Awesome stuff dude. Honest question though: isn't it the surface being too large that causes the big ballooned raindrops to burst ? Similarly, it's the lackluster surface tension of a tiny droplet -shrapnel- that causes it to remain in a stable state and not burst, right?
3:37 how can the drops be bigger close to the ground if once threy break they dont reform again? And on top of that shouldnt the increase in air presure decrease the amount of water necesarry for the drop to burst?
3:54 did he say clouds are made of water vapor? Cluds are made of tiny liquid droplets suspended in the air (or sometimes ice crystals). I know it's a common misconception but wasn't expecting to hear something like this in this channel /:
Why do the droplets (or ice crystals) stay together to be clouds? Or is it just that the region of the cloud is the region where the conditions are such that the droplets form? (I'm thinking of partly cloudy to mostly sunny conditions, not fully cloudy.)
Great conversation. That animation at 8:00 was really off-the-mark. It looked nothing like actual raindrop shape or what was being described. The video goes on to show actual raindrops just 30 seconds later. Why this error?
so I guess not every raindrop is formed around microdust particle, after raindrop bursts dust will stay only with single drop and rest of them fall on the ground as a water only, right?
So rains with bigger droplets are most likely from lower clouds? The end conclusion about the distribution coming from the shrapnel doesn't quite make sense, because there are some rains that have bigger drops than others.
Pretty sure clouds are composed of small droplets of water, not water vapor. They surely contain water vapor, but water vapor is invisible, so you wouldn't see it. Has anyone done an experiment to see if water vapor condenses without a seed? You could purified air. I am sure we could make some. How big is the typical seed? How does seed size affect droplet formation?
If a raindrop has a microscopic piece of dust at its core, and the drop grows to large size, that raindrop will then explode. But only one or a few of the resulting drops will dust cores. Alternately, as a drop grows and falls, it will clear the air of microdust, trapping them internally, so all the resulting micro raindrop will have an even density of dust.
Minutephysics - 'Why Raindrops Are Mathematically Impossible' if you want to see why raindrops need that starting seed. TL;DR, small starting drops (talking atoms worth) evaporate faster than they grow. Rain's Dirty Little Secret - minuteRarth for a more basic description
To simple, this was a brain experiment more than the whole study of physics inside clouds. It's ok but you never mentioned the other important variables: altitude/temperature, time and freezing moments, and how what you described is but a tiny fraction of a cloud and its inner turbulence. A cloud is more complex physically than a star, and imo equally beautiful… you just weren't up for the challenge, I guess.
Thank " god " for people who love minutiae! So that I can learn from their sufferings, they give me knowledge. Thanks again. Edit: butterflies and cyclones.
You should get into another department on Nottingham University, who is using ML to stop slavery in pakistan.. Al Jazeera has an episode on it, it is really interesting.
Calling it surface tension is not really accurate and perhaps a too-classical perspective. The whole droplet is holding that shape, not just the surface.
Having been a pilot for many years and flying through various inclement weather situations I have the following observations to bounce off the physicists. 1. There is time for the rain drip to cycle through the various sizes due to updrafts. A perfect example is a hail stone. It starts small and freezes at height, then falls and picks up water on the surface. It gets picked up again and refreeze. Like an onion it has layers and each layer is a trip through the storm. The stronger the storm, the more layers and larger of the hail. Therefore, if the storm is the same as a hail storm, but the water doesn't freeze, why wouldn't it still go through the cycle? 2. Flying through the mid level of nimbostratus is where I have hit what I would consider the largest raindrops I have seen. At those points it sometimes is like going through a sheet of water, there doesn't seen to be individual drops just a wall of water to punch through.
@@JoseAbell I think that is more metaphorical -- the rain is so dense that it "feels" like a solid (especially if you are moving into it). I've experienced something like this in thunderstorms in the midwest where it is like being embedded in a waterfall.
Reminds me of Douglas Adams book.. I think it was"So Long and Thanks for the Fish"... With a truck driver who is constantly in rain. And has his own scale of different rain types.
Fascinating! He should talk about the weather on other planets too. For example, he could talk about how raindrops of liquid methane on Titan would fall differently than on Earth.
Would they not also fall faster though due to the thinner atmosphere? I wonder if one effect would cancel or partially tend to cancel out the effect of the other? Would be fascinating to see. Even if that is true, slightly larger droplets at a greater velocity would make for some effect.
What about sulfuric acid raindrops on Venus? Different surface tension, different atmospheric pressure and different g value might mean there's enough time for multiple cycles of formation-disintegration…
I know! I'd never heard it explained that way before. Surface tension has always been something that I just took as given without thinking about "why does this exist?", but suddenly it makes so much sense.
Veritasium put out a fascinating video on period doubling, the Feigenbaum constant, and the practical effects in real life like population modeling. I couldn't help but think that falling raindrops fit into this phenomenon. If given enough time falling through atmosphere, would we see chaotic droplet splitting/recombining and witness period doubling?
That flour-raindrop experiment is beautifully simple. Definitely should be done in schools a lot more.
I pity the fool who goes to school near death valley. 50 years old - still waiting to get their 2 grade science grade. They can't complete their raindrop lab.
@@DackxJaniels That might be actually why this simple experiment is almost never done in schools (It is somewhat likely that someone had tried it in a school setting.)
The experiment is very weather depended so you need to prepare it for one of those rainy days. And I think having that prep work and then the experiment on standby is a bit more of a hassle then in worth. Though of course there plenty of places in the world that get rain pretty regular so it might be something worth doing then.
@@Cythil The only place to do this experiment is next to a lit BBQ. Thats the only way to ensure it rains.
Fraser Steen Experiments might be interesting but they are not that efficient tools for learning. But they might spark interst. However, they interfere routine, which is the most important oart of learning.
Doesn't rain for 3-5 months in a row in the summer in the bay area.
I'm a Naval Architect. I've always been told at uni that the two resistances ships have to overcome are friction resistance and wave-induced resistance. Once or twice been told that wave-induced resistance was different from friction resistance because of surface tension...
But never quite understood why and that's something this video addresses perfectly. Hydrogen bonds cause water molecules to stay together, and that gives rise to this potential energy on the very surface (or the boundary layer between two fluids, in this case, water and air). This channel is just one marvellous thing for all of the curious people who love science and don't really have someone to learn from or talk to about it.
Froude was right and didn't even know why!
PS: now friction resistance which encompasses tons of different resistances like pressure resistance, viscous resistance, viscous pressure resistance, etc is a whole world apart... *As Sir Horace Lamb would put it: **_I am an old man now, and when I die and go to heaven, there are two matters on which I hope for enlightenment. One is quantum electrodynamics and the other is the turbulent motion of fluids. About the former, I am really rather optimistic._*
Im so grateful to Brady and Professor Merrifield for making these clips. Interesting science!
This is exactly the information I have been searching for most my life. I just did not know it. But now that I do, I am happy.
Yesssss I missed you Sixy Symbols!
The stereotypical rain drop shape I guess comes from a dripping water tap.
It does.
@pjd412 Shouldn't low aerodynamic drag be a much flatter shape, shard-like? I don't think I can agree: practical aerodynamics is a very ancient subject manifesting in spears and arrows for example, which do not look at all like the stereotypical drop shape.
??
That was a really good explanation of surface tension, that makes a lot of sense.
Seems i am watching this channel for quite so time now. For the first time I notice the professor is turning old! I hope he stays well for a long time. I always love listening to his explanations. It makes it look so easy (until you do the math).
Hi Brady,
I would love to see some follow up videos with the professors. It could be interesting to hear how developments such as gravitational wave astronomy and just the passage of time may have modified previous statements / answers to your questions.
More Mike Merrifield please!!
Just yesterday my son asked me about clouds and rains and ping... With almost perfect timing this great video pops up thx
I feel like rain drops in summer that go along with thunderstorms are much bigger than a few millimeters. Rain seems really diverse from my perspective at least, where you can either have a very tiny spray or very big blobs...
That was FASCINATING! I NEVER would have guessed that when raindrops get too big they basically explode from the "rising" air flow!! That's soooooo COOL!!!
-First time I watch a video = LIKED!
-First time I liked a video = SUBSCRIBED!!
I just CANNOT WAIT to explore the rest of your videos!!! Wo0T-W0oT!!
Actually rain can form in a different way. The kind of rain that Mike described, where vapor is condensing on little particles, forming small drops, and those can bump into each other forming bigger drops (coalescence), takes many hours or even days to develop any rain. That is the sort of rainy day stuff, where a large cloud deck (stratus) is formed in a weather front for example. When you get a shower from a smaller cloud (cumulus) or a thunderstorm (cumulonimbus), rain develops in a different way. Water vapor condenses into tiny droplets at the base of the cloud and move to higher in the cloud due to convective motion. The temperature drops with the altitude and below about 12 degrees Celsius, ice crystals start forming. Water vapor (100% relative humidity) sublimates on the ice crystals, creating snow. As the ice crystals grow, the relative humidity drops, and therefore the water droplets evaporate and so the humidity stays high. The liquid water droplets "feed" the vapor that then sublimates into ice. When the ice crystals grow big enough they start to fall and get in warmer air at lower altitude where they melt into raindrops. Also on their way down they encounter a lot of droplets so they grow bigger due to coalescence. This process is way quicker and is the reason that a thunderstorm can develop rain in (much) less than an hour.
I'm amazed by Brady's question. They are so precise
You forgot to mention if the common visual image of a raindrop is real or not. I am left to assume that raindrops are spheres and never go into that well down drop shape. I imagine a drop shape comes from when a portion leaves a larger portion and some adhesion occurs so a bit is drawn off slower and the sphere elongates. But does this mean water drops should always end up spherical?
The "common" raindrop shape most likely comes from seeing something drip. Just before a drop falls from something wet, it looks "drop shaped". After that you would need special equipment to see the real shape.
Without gravity raindrops should have a spherical form, because then it has the smallest surface area for a given volume.
They are actually flattish at the bottom once they start falling, due to effects of the wind. There's some vids around. Funny thing I see it with my naked eyes living in a 30 story apt in the middle of the building. During a storm, the air that hits the building where I am has nowhere to go but up (as seen when I open the balcony door, and one to the hallway heh). So often the wind speed upwards = the falling speed and I get rain drops floating around the balcony almost perfectly suspended in air. In snowstorms it's often I see nothing but upwards snow if there's a north wind.
Thanks for that explanation Prof Merrifield.
Keep them coming please this is my fav channel on youtube more of prof ed copeland please
Truly fascinating
It's 4 am (Austria), what am I doing here? Can't stop watching these videos!
Great video! Very informative
That was fun, thanks. Enjoyed the discussion of the early experiments. But there was some fascinating physics left out, such as how rain drops could collect/merge with other drops as it falls...depends on size (effective cross-section radius) of falling drop and target drop. What would be really cool is to discuss how ice crystals form and grow in cold clouds to generate snow. Much different process than the collision/coalescence process he described. I always enjoy the atmospheric phenomena discussions in Sixty Symbols!
I almost went to school at Newcastle just to see you. We really appreciate you
Fascinating!
Excellent video.
Nice video. I worked on this topic long time ago; the Marshall-Palmer size distribution is out of time, because of the behaviour of the diagram near to zero. Many other size-distributions came out, I remember the beautiful papers of Ulrich, and many other physicists, in the 80' and 90's. Some multiparameter Gamma-distributions were born, which more or less adapted their shape to experimental data. But the big question which came from the Marshall-Palmer work, was: what's the relationship between Rainfall rate and the size of drops?
thats the best explanation of surface tension
Got a typo here at 1:52/11:40. ... med 0.16 - 0.32 cm ... large 0.14 - 0.36 cm. Just love watching your video.
Nice video, but what has to be mentioned as I think, is, that without hail there would be no rain. Coalescing clouddrops can only form very tiny droplets. Bigger raindrops were frozen before, and when they melt, they become raindrops. That's where all those interresting phenomena occur. - And sometimes the hailstone has no time to melt before hitting the ground. The story of raindrops is very interresting indeed, and full of wonders (one of which is the rainbow of course).
Neat topic and followup questions, thank you!
I'm in Southwest Florida, USA and one thing I've noticed about storms is that the initial rain that falls is much bigger in size than the actual storm.
It's not very intense with the big droplets, but it seems the individual droplets are bigger at the start of the storm the the main part of the storm.
there are down-drafts at the edge of a thunderstorm. when the surrounding air is moving along with the drop, the air resistance is lower, so drops can grow bigger.
So cool!
i always wondered about the speed at which your car is travelling and the number of drops/amount of water which hits your windshield in the rain. I imagine there are difference in stopped , slow, faster relative to the speed of the falling rain, very fast when aerodynamics become significant, size/amount/speed of rain etc etc, some rich discussion there maybe.
The beard really adds an air of regality to Professor Merryfield.
Perfect timing for me; was re-watching the third matrix movie last night and couldn't help myself cringing a little at one of the final scenes where there's a slow-motion CGI shot of Neo's fist going through the rain, hitting Smith in the face, where the falling rain drops are shaped like long rods.. Of course by the movies own logic that can be explained by the matrix glitching out and losing som of the calculations that deal with surface tension and air resistance, but as far as realism goes it looked kind of comically bad to my now-older eyes :p
9:58 I want this GIF for my life
Seems like at least some of the shrapnel drops could be re-lifted to the upper deck of the cloud via updrafts... or is that really a niche phenomenon? I recall hearing that hail is formed when a storm has these strong updrafts that keep throwing a raindrop to the top of the cloud, where it freezes, then falls and wets again, to be re-lifted to re-freeze. This is how hail chunks the size of robin eggs or bigger are formed... or so I was told.
So what would happen if you'd simulate rain in a big vacuum chamber? If there's no air resistance will the drops of water be larger, would they not balloon up?
In a vacuum, the drops would boil into vapor. Liquids usually don’t stay liquid without pressure.
Brady's questions where quite on spot in this video.
Some of the water in a cloud is in liquid form, that's why we see them, so I'm curious as to what causes the water to start to fall out as rain? Clouds can pass over a large region before they start to condense as rain, is it just the cloud getting dirty from some saturated amount of "seeds"?
It basically has to do with surface tension. The liquid water you mention is attached to small dust particles. As the liquid water further condenses, the surface tension keeping it held around the dust breaks and causes it to fall to earth.
the drops need a certain size and therefore mass to be heavy enough to overcome air resistance.
I guess there being wind would change things a bit. Also the atmospheric pressure. Like hail that forms in an upwards current until the wind can't hold it in the air anymore and then it falls down. Would a less dense atmosphere, or a lesser gravity, imply larger raindrops, or even streams of water?
He could have saved himself some time by just asking Forrest Gump. He's had more than enough experience to provide some insight :)
Please explain hail next.
At what size will the surface tension of the water be too much for the aero to cause the parachute and subsequent breakup.
I would imagine that the downdraft that often occurs at a storm front might prevent the large drops from experiencing a ballooning effect, hence large heavy raindrops?
Awesome stuff dude.
Honest question though:
isn't it the surface being too large that causes the big ballooned raindrops to burst ?
Similarly, it's the lackluster surface tension of a tiny droplet -shrapnel- that causes it to remain in a stable state and not burst, right?
Maybe in England the raindrops only get to 1 mm in size but here in Arizona they get big enough to hurt you. Explain that!
06:20 "From the raindrop's perspective" should be this man's autobiography.
what about solar forcing of rain through ionization or particles?
Someone's never been in tropical rain. I've been in four inches in four minutes, that stuff was coming down the size of small marbles.
so, if the drops break up to smaller pieces right away, what is the process that causes larger drops to reach the group (as in the nasa picture)
brilliant, thank you! (:
3:37 how can the drops be bigger close to the ground if once threy break they dont reform again?
And on top of that shouldnt the increase in air presure decrease the amount of water necesarry for the drop to burst?
rain is like star formation....more small than big...nature is relatively similar everwhere
De Broglie effect. Differential speed jet stream and thermo dynamic convection cross flow, compression interaction cloud formation. Thermo dynamic density variation, droplet formation.
Circumference of latitude, different earth surface speed also.
3:54 did he say clouds are made of water vapor?
Cluds are made of tiny liquid droplets suspended in the air (or sometimes ice crystals).
I know it's a common misconception but wasn't expecting to hear something like this in this channel /:
Why do the droplets (or ice crystals) stay together to be clouds? Or is it just that the region of the cloud is the region where the conditions are such that the droplets form? (I'm thinking of partly cloudy to mostly sunny conditions, not fully cloudy.)
Great conversation. That animation at 8:00 was really off-the-mark. It looked nothing like actual raindrop shape or what was being described. The video goes on to show actual raindrops just 30 seconds later. Why this error?
so I guess not every raindrop is formed around microdust particle, after raindrop bursts dust will stay only with single drop and rest of them fall on the ground as a water only, right?
i wish this man was my dad
So rains with bigger droplets are most likely from lower clouds?
The end conclusion about the distribution coming from the shrapnel doesn't quite make sense, because there are some rains that have bigger drops than others.
Maybe they are bigger because the original "Mega Drop" was bigger
Well now you have to do one about the "rain" drop shape of the methane on Titan.
Can't wait to see what the raindrops of liquid methane on Titan looks like :-)
Pretty sure clouds are composed of small droplets of water, not water vapor. They surely contain water vapor, but water vapor is invisible, so you wouldn't see it.
Has anyone done an experiment to see if water vapor condenses without a seed? You could purified air. I am sure we could make some.
How big is the typical seed? How does seed size affect droplet formation?
Daniel Plainview out here taken pictures of snowflakes
raindrop drop top
One question :
Why is this channel called Sixty Symbols?
Look at old videos. Each used to be about a symbol.
I guess they ran out ;)
@@hugopelland Thanks a lot!
I wonder if hail in a supercell is formed from the larger pre-balloon water drop or the small remnants after the inflated water drop pops?
If a raindrop has a microscopic piece of dust at its core, and the drop grows to large size, that raindrop will then explode. But only one or a few of the resulting drops will dust cores.
Alternately, as a drop grows and falls, it will clear the air of microdust, trapping them internally, so all the resulting micro raindrop will have an even density of dust.
Minutephysics - 'Why Raindrops Are Mathematically Impossible' if you want to see why raindrops need that starting seed. TL;DR, small starting drops (talking atoms worth) evaporate faster than they grow.
Rain's Dirty Little Secret - minuteRarth for a more basic description
Don't forget "How mushrooms make it rain", also by MinuteEarth.
To simple, this was a brain experiment more than the whole study of physics inside clouds.
It's ok but you never mentioned the other important variables: altitude/temperature, time and freezing moments, and how what you described is but a tiny fraction of a cloud and its inner turbulence.
A cloud is more complex physically than a star, and imo equally beautiful… you just weren't up for the challenge, I guess.
Thank " god " for people who love minutiae! So that I can learn from their sufferings, they give me knowledge.
Thanks again.
Edit: butterflies and cyclones.
You should get into another department on Nottingham University, who is using ML to stop slavery in pakistan.. Al Jazeera has an episode on it, it is really interesting.
No
8:12 is it a dog or a cat?
:D last sentence answers title 11:07
👽Everybody knows what they know, true knowledge is knowing what you don't know.👽
in Vermont, the man is only known as "Snowflake Bentley"
Since when is astronomy about 'anything that's in our skies'?
but why is the raindrop shape called that
Calling it surface tension is not really accurate and perhaps a too-classical perspective. The whole droplet is holding that shape, not just the surface.
So are raindrops never "raindrop shaped"?
I missed the part that raindrops turn into cats and dogs.
"...so the raindrops which fall on your head probably are more or less round."
Isn't everything more or less round to a physicist though?
"Assume a spherical cow..."
@@trafalgarla "In an airless, frictionless space..."
😂😂😂😂
More or less.
@@trafalgarla I never understood the spherical cow metaphor because topologically speaking a cow is more similar to a torus
These videos are like sitting down and having coffee with some extremely bright people , something everyone can benefit from. keep it up.
'
I was actually having a cup of coffee while watching this video.
@@ZeedijkMike ditto :)
Always great to see Prof. Merrifield!
My favorite weatherman is back!
Happy to see u back prof
Having been a pilot for many years and flying through various inclement weather situations I have the following observations to bounce off the physicists.
1. There is time for the rain drip to cycle through the various sizes due to updrafts. A perfect example is a hail stone. It starts small and freezes at height, then falls and picks up water on the surface. It gets picked up again and refreeze. Like an onion it has layers and each layer is a trip through the storm. The stronger the storm, the more layers and larger of the hail. Therefore, if the storm is the same as a hail storm, but the water doesn't freeze, why wouldn't it still go through the cycle?
2. Flying through the mid level of nimbostratus is where I have hit what I would consider the largest raindrops I have seen. At those points it sometimes is like going through a sheet of water, there doesn't seen to be individual drops just a wall of water to punch through.
Guys! Can someone please address this? Sheets of water on the sky? I need a video.
@@JoseAbell I think that is more metaphorical -- the rain is so dense that it "feels" like a solid (especially if you are moving into it). I've experienced something like this in thunderstorms in the midwest where it is like being embedded in a waterfall.
*Brady's reaction:* _"Huh..."_
Reminds me of Douglas Adams book.. I think it was"So Long and Thanks for the Fish"... With a truck driver who is constantly in rain. And has his own scale of different rain types.
Great video, really well paced as well!
Fascinating! He should talk about the weather on other planets too. For example, he could talk about how raindrops of liquid methane on Titan would fall differently than on Earth.
I wanna see that.
With a thinner atmosphere I'd expect droplets could get far bigger before hitting the threshold that would trigger the splitting action.
Would they not also fall faster though due to the thinner atmosphere?
I wonder if one effect would cancel or partially tend to cancel out the effect of the other?
Would be fascinating to see. Even if that is true, slightly larger droplets at a greater velocity would make for some effect.
@@martingrundy5475 The atmosphere is *not* thinner; it's actually *thicker.*
What about sulfuric acid raindrops on Venus? Different surface tension, different atmospheric pressure and different g value might mean there's enough time for multiple cycles of formation-disintegration…
Interesting and the surface tension energy was well explained. Thank you for making this video!
that part really was well-explained.
I know! I'd never heard it explained that way before. Surface tension has always been something that I just took as given without thinking about "why does this exist?", but suddenly it makes so much sense.
So then you are clear about why some liquids have less surface tension than water?
I've been missing sixty symbols vids! Always love a Professor Mike vid as well.
Ahaha, brilliant! I'm really getting back into these science education videos now that my own education has hit a bit of a speed bump.
I didn't know it was my birthday today. Thanks for the 60 symbols vid!
Why does the NASA picture at 3:34 contratict the explaination he gives later in the video??
You're right! It shows bigger drops at low altitudes. I demand an explanation, professor Merrifield!
@@philippegirard6722 Maybe the picture shows mostly the cloud and the splitting happens later OR these raindrops are just too tiny to split (drizzle)
Veritasium put out a fascinating video on period doubling, the Feigenbaum constant, and the practical effects in real life like population modeling. I couldn't help but think that falling raindrops fit into this phenomenon. If given enough time falling through atmosphere, would we see chaotic droplet splitting/recombining and witness period doubling?
I love the relaxed chat vibe of this channel.
How long does it take for a raindrop to fall? What is it's maximum velocity? How much kinetic energy is there in a drop?
So if large raindrops go kaboom on the way down, how do we occasionally get downpours where the individual drops are huge?