Sixty Symbols - 2019-09-01
All about how raindrops form and fall. Featuring Professor Mike Merrifield. More links and info below ↓ ↓ ↓ More with Professor Merrifield: http://bit.ly/Merrifield_Playlist Our weather-themed playlist: http://bit.ly/Weather_Videos Professor Merrifield on Twitter: https://twitter.com/astromikemerri Deep Sky Videos astronomy videos: https://www.youtube.com/user/DeepSkyVideos Papers from this video... STUDIES OF RAINDROPS AND RAINDROP PHENOMENA ftp://ftp.library.noaa.gov/docs.lib/htdocs/rescue/mwr/032/mwr-032-10-0450.pdf THE DISTRIBUTION OF RAINDROPS WITH SIZE https://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%281948%29005%3C0165%3ATDORWS%3E2.0.CO%3B2 Single-drop fragmentation determines size distribution of raindrops 10.1038/nphys1340 Visit our website at http://www.sixtysymbols.com/ We're on Facebook at http://www.facebook.com/sixtysymbols And Twitter at http://twitter.com/sixtysymbols This project features scientists from The University of Nottingham http://bit.ly/NottsPhysics Patreon: https://www.patreon.com/sixtysymbols Sixty Symbols videos by Brady Haran http://www.bradyharanblog.com Email list: http://eepurl.com/YdjL9
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.
@Zeedijk Mike ditto :)
"...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?
@0x0 That's the point! You missed the joke, physicists tend to simplify things, cows are never genus-0. Although they are not tori either, consider noses and mouths.
@0x0 Because the math is easier on a sphere than a torus!
@0x0 I hope the torus/bull pun was intended... I highly appreciated it.
@IceMetalPunk the pun was intentional but I was totally serious with what I said
Isn't round just don't the property of not having any sharp edges? By this definition of round pretty much everything is round.
Always great to see Prof. Merrifield!
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.
@Jose A. Abell M. 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.
Happy to see u back prof
My favorite weatherman is back!
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.
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.
Brady's reaction: "Huh..."
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.
@Martin Grundy 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…
@Adam Renwick And way different temperatures as well. I suppose it depends on how high up the raindrops form. If it's still at a very high atmospheric density, then I imagine the raindrops may not even fall fast enough to break up in the same way. I don't know. It depends on the Reynolds number I imagine.
I don't think the physics would be very different. Different temperatures, densities, molecular makeup, but it's still about liquid drops falling through a gas. I could be wrong but the processes that involve sfc tension, coalescence, collisions would still primarily depend on aerodynamics. Well, maybe the electrostatic forces in some dry atm could influence drop growth...maybe. Fun to think about.
@John Callahan But how fast the droplets fall determines whether or not you have turbulent flow. So the atmospheric density, surface tension, gravity, etc. should matter.
I've been missing sixty symbols vids! Always love a Professor Mike vid as well.
Yesssss I missed you Sixy Symbols!
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?
He could have saved himself some time by just asking Forrest Gump. He's had more than enough experience to provide some insight :)
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.
“The raindrops that fall in your head are probably more or less round” i think something in me shattered because of that statement 😔
Rain drops turn into little umbrellas, and I think that's really lovely.
I didn't know it was my birthday today. Thanks for the 60 symbols vid!
That was a really good explanation of surface tension, that makes a lot of sense.
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 love the relaxed chat vibe of this channel.
Great video, thank you! I was just thinking about making a shader for rain, making raindrops different in size for different types of weather would be a very neat little detail :)
1:50 this imperial to metric conversion is bad even for a physics channel.
06:20 "From the raindrop's perspective" should be this man's autobiography.
Search YouTube for "The Elements in Six Dimensions"
brilliant, thank you! (:
Would love to hear a similar discussion of how interstellar hydrogen and ‘dust’ behave in star formation !
It's amazing how you can still learn something new about something as common as raindrops.
I love that a few droplets from the top of the ballooning drop actually travel upward momentarily after the burst.
"fallen 10 miles" excuse me wtf?
@smartereveryday needs to get his phantom out and find out what rain really looks like
7:50
You can do that yourself the easy way for me was keeping a mouth full of water then while at a great hight just open your mouth towards the ground and the water in your mouth will fall and there’s a high chance a single large water droplet will be present with a bunch of smaller ones around it but halfway down the large droplet will be whole but it’ll explode in midair creating lots of other droplets then it hits the ground lol I found that out and how water works like that when I was a teen lol thought it was cool because I never seen a droplet explode in midair like that
Neat topic and followup questions, thank you!
I loved seeing the professor (no Brady :' ( ) at the university open days! It truly felt like meeting a celebrity of mine.
I was surprised to hear no mention of the "shot tower" used in days past to manufacture musket balls/round shot. There is a beautiful example of one such in downtown Melbourne, under a dome forming part of a railway station cum shopping mall called Melbourne Central. Basically, it's just a tall tower made of brick from the top of which measured drops of molten lead were allowed to fall to a bed of sand. The height of the tower gave the molten lead time to form a ball and grow sufficiently cool as to retain that shape upon reaching the bottom.
When you say he took drops of known size at 1:40, how exactly can one create drops of known sizes?
The solemn tone of the last segment made me think you were going to till us that Professor Merrifield had passed or something
I like the cable organization, congrats to the IT
Thank you! As always amazing!
Awesome video! Will we be seeing any more videos with Professor Ed?
Brady's questions where quite on spot in this video.
So if large raindrops go kaboom on the way down, how do we occasionally get downpours where the individual drops are huge?
9:58 I want this GIF for my life
Just yesterday my son asked me about clouds and rains and ping... With almost perfect timing this great video pops up thx
"we nei:d a sei:d"
That something so commonplace would turn out to be so fascinating!
Thanks for that explanation Prof Merrifield.
awesome video. how many times were you gonna ask that same question at the end tho? lol
Fraser Steen - 2019-09-01
That flour-raindrop experiment is beautifully simple. Definitely should be done in schools a lot more.
Cythil - 2019-09-02
@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.
Charlie Quick - 2019-09-02
@Cythil The only place to do this experiment is next to a lit BBQ. Thats the only way to ensure it rains.
Moist Mayonese - 2019-09-03
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.
Kevin Luo - 2019-10-08
Doesn't rain for 3-5 months in a row in the summer in the bay area.
Timothy Reeves - 2020-09-27
Charlie Quick or you can wash your car. That often works.