[HN Gopher] When Water Flows Uphill [video]
___________________________________________________________________
When Water Flows Uphill [video]
Author : ColinWright
Score : 228 points
Date : 2024-06-11 10:33 UTC (1 days ago)
(HTM) web link (www.youtube.com)
(TXT) w3m dump (www.youtube.com)
| theogravity wrote:
| The water ball maze at the end is really cool.
| bcraven wrote:
| It's technically a labyrinth rather than a maze as there's a
| single path.
| ARandomerDude wrote:
| It just needs a Minotaur.
| m_st wrote:
| Barely related, but in Bern Gerechtigkeitsgasse they made an
| almost hidden art installation so that the Stadtbach (city
| stream) flows uphill in a small part. It's very fun to watch.
|
| https://de.wikipedia.org/wiki/Stadtbach_(Aare)
| mavhc wrote:
| How does it work?
| wumms wrote:
| "The city stream is redirected in an underground, invisible
| loop so that it flows backward, or upstream, for a short
| distance. However, the backflow is always just outflow in
| reality. This is because the watercourse has a continuous
| gradient." (translated from a Google result excerpt of this
| paywalled article [0])
|
| [0] https://www.derbund.ch/warum-der-stadtbach-aufwaerts-
| fliesst...)
| tomthe wrote:
| Yes, that seems to be the explanation. I found a few
| pictures here: https://www.komoot.com/de-
| de/highlight/615007 but they also do not show how it works.
| dools wrote:
| I remember watching those little droplets form and bonce arond on
| the old solid stove tops we had when I was a kid, I loved it!
| tomw1808 wrote:
| I remember watching that video. About 10 years ago. Fascinating
| then, fascinating now.
| Karellen wrote:
| "The difference between science and screwing around is writing it
| down"
|
| -- Adam Savage
| eleveriven wrote:
| The importance of documentation
| m-i-l wrote:
| Throughout the video I was wondering what possible practical
| applications there could be. I got it at the end: "we use this
| effect to engage people who are otherwise not so interested in
| science".
| mistermann wrote:
| I wonder if this could be used as the opening scene of a
| persuasive documentary on vaccines, it's pretty mesmerizing.
| Maybe an innocuous "How does it work?" theme with 10 phenomena,
| with one of them being vaccines.
| mdp2021 wrote:
| It is still best to help the ignorant leading it to not being
| mesmerized.
| mistermann wrote:
| When it comes to vaccines in a comprehensive scope, I
| suspect there is no Human that is not at least somewhat
| ignorant (or not all knowing), and delusional to at least
| some degree. The "science" aspect is but one part of a much
| more complex picture.
| mdp2021 wrote:
| So let us have awareness campaigns, and make them
| unassailable by being perfectly honest - instead of
| furthering attempted manipulation ("mesmerizing people
| for persuasiveness through innocuous documentaries about
| the wonderful") as if it were aproblematic behaviour, and
| as if normal actually-adults would not be consequently
| exposed to dubious campaigns, with dubious results.
|
| I do not know about many places around the world, but in
| some areas it is normally told to children in primary
| school that "well, before these milestones you had an
| important risk of measles or poliomyelitis" - just as
| part of the history of science and achievements, primary
| school level. Which again suggests that treating people
| like adults - even very "underage" - remains an important
| recipe to obtain, in the end, Adults.
| theginger wrote:
| Could be used to win bets for free drinks in a bar, shame you'd
| probably get kicked out for wielding dangerously hot metal
| plates before you've had a chance to drink them.
| actionfromafar wrote:
| Never a good idea to drink hot metal plates
| foobarbecue wrote:
| Earlier in the video they say it could be used to cool
| microchips.
| kube-system wrote:
| Seems like a stretch... the examples in the video were around
| 400-500F
| doublerabbit wrote:
| If we somehow ended up extinguishing gravity and we start
| floating upside down. Good to know we can now post water
| upwards.
|
| Although thinking about it, water would float upwards too..
| HPsquared wrote:
| Heat engines are cool. (These are an example of a heat engine:
| something that converts thermal energy into mechanical work)
| nojs wrote:
| If you like watching water flowing uphill, I highly recommend
| paying this spot in Taiwan a visit [1]. It's a very clever and
| convincing optical illusion.
|
| 1. https://eng.taiwan.net.tw/m1.aspx?sNo=0002016&id=A12-00284
| calebm wrote:
| Water flows uphill all the time - all you need is an Eddy
| (https://en.wikipedia.org/wiki/Eddy_(fluid_dynamics))
| kurthr wrote:
| I was just going to say, go to the beach. It's wind rather than
| steam providing the motion, but similar.
|
| Watch the waves roll up the sand slope!
| unnah wrote:
| The practical way to get water to flow uphill is of course the
| https://en.wikipedia.org/wiki/Siphon - always amazing in its
| own way.
| TheRealPomax wrote:
| If you enjoy this bit of physics, and you're wondering if water
| flowing the "wrong direction" is something that happens in real
| life, aside from the other comments about wind-induced
| counterflow, definitely look up the Severn bore[1], too, which is
| a tidal bore that makes the river Severn flow inland twice a day,
| with wave fronts that can be large enough for folks to "surf
| upstream".
|
| [1] https://en.wikipedia.org/wiki/Severn_bore
| krunck wrote:
| The title should include that it is from 2013.
| alamortsubite wrote:
| The grooves at ~2:56 [1] are a result of the machining process?
|
| [1] https://youtu.be/zzKgnNGqxMw?si=0Qlrd-lcyAUvJHg8&t=176
| pge wrote:
| The Leidenfrost effect is also one explanation often given for
| why walking on hot coals without burning your feet is possible.
| The theory is that the sweat on your feet evaporates creating a
| vapor barrier that insulates the feet from heat.
| bragr wrote:
| Huh, this a a solved problem. You can walk on coals because
| both the ashy coals and your skin are poor conductors of heat,
| your feet are only in contact with the coals briefly, and your
| blood flow carries the heat away from the contact points. The
| only trick is to walk gently yet quickly on them.
___________________________________________________________________
(page generated 2024-06-12 23:02 UTC)