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May 10

Chemical diagram

Hello, does anyone know what "E" means in this diagram?

https://en.wikipedia.org/wiki/Cinnarizine#/media/File:Cinnarizine.svg ~2026-28220-47 (talk) 09:57, 10 May 2026 (UTC)

• E–Z notation. Abductive (reasoning) 10:10, 10 May 2026 (UTC)

  Thank you. ~2026-28220-47 (talk) 17:14, 10 May 2026 (UTC)

Flow of the entire ocean?

What's the order of magnitude, in Sverdrups, of the entire flow / circulation of the world's oceans? -- Avocado (talk) 16:48, 10 May 2026 (UTC)

• 10,000 sverdrups. If the Gulf Stream is 150 sverdrups at its max, and the Antarctic Circumpolar Current is 125, then all the other surface currents bring that up to 1,000 sverdrups. But then the internet says the deep ocean currents are 90% of all currents. Abductive (reasoning) 19:07, 10 May 2026 (UTC)

Those dimensions don't fit. A sverdrup is a volume per time, which is also a velocity integrated over some surface area, typically the cross sectional area of some straight or ocean current. For the flow of the world's oceans, you have to integrate over the volume of the ocean, giving length to the fourth divided by time. Or did I misinterpret your question? PiusImpavidus (talk) 19:08, 10 May 2026 (UTC)

Obviously the flow of the entire ocean is 0. But if you just sum up all the currents then you can estimate total sverdrups. Abductive (reasoning) 19:22, 10 May 2026 (UTC)

I'm an idiot, so it's not obvious to me. Explain, please? ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:08, 11 May 2026 (UTC)

Sure, if you look at the ocean current and thermohaline circulation articles you will see that all the ocean's waters circulate, some along the surface, some returning below, making their net movement zero. They have to, otherwise all the water would build up on one side of the Earth. Abductive (reasoning) 02:33, 13 May 2026 (UTC)

Is this connected to why the Pacific sea level is higher than the Atlantic? ←Baseball Bugs ^{What's up, Doc?} carrots→ 02:47, 13 May 2026 (UTC)

No, the Pacific is less dense. Even so, since it is consistently 20 cm higher, the net flow is zero. Abductive (reasoning) 02:53, 13 May 2026 (UTC)

OK, that sort of makes sense. (Maybe I should change my user name to Atlantic.) ←Baseball Bugs ^{What's up, Doc?} carrots→ 11:36, 13 May 2026 (UTC)

One way of defining the total flow is by integrating the infinitesimal volume-velocity vector over the volume. Measured relative to the centre of mass of a closed system of a flowing fluid, this will yield the zero vector, even in the case of a fluid uniformly circulating in a doughnut-shaped ring, in which the desired result would be the volumetric flow rate through any cross section. A more interesting way is by integrating the magnitude of the flow rate, which can only be 0 in the case of total stagnancy. Applying this to the case of a ring, we see the dimensionality problem; we get dimension ${\mathsf {T^{-1}L^{4}}}$ instead of the dimension of the sverdrup, ${\mathsf {T^{-1}L^{3}}},$ as pointed out above by a fearless yet devout editor. Also, turbulence may unduly form a high contribution.

One way to give a sound (but perhaps not very satisfying) definition may be by considering all ways of partitioning the volume into compartments separated by two-dimensional permeable walls. (Such a partitioning can be modeled mathematically as a directed graph whose nodes are the compartments and whose edges ate the walls, labeled with the flow rate through that wall. If these flow rates are properly signed, this graph should satisfy Kirchhoff's junction rule.) Now define the global flow rate as the absolute value of the maximal flow rate through any wall of any way of partitioning. Considering only a finite number of partitionings will give a lower bound. Adding up flows instead of taking the maximum will usually mean double counting (as would happen when placing two walls in a ring).  ​‑‑Lambiam 09:47, 11 May 2026 (UTC)

Are the calculus functions gradient, divergence and curl called for here? ~2026-21660-55 (talk) 12:23, 11 May 2026 (UTC)

The gradient is the same mathematical entity as the gradient vector field, of which the velocity field in mathematical physics is an instance. The divergence of the flow velocity field of an incompressible fluid is 0. This can be seen as a continuous version of Kirchhoff's rule. The curl tells us how fast the velocity vector changes direction along the path length. A tight turn means a high curl. Since we are only interested in the magnitude of the flow and not the direction, it is unlikely to be relevant.  ​‑‑Lambiam 15:19, 11 May 2026 (UTC)

May 13

age of old trees

I always thought the bristlecone pine was the longest-lived tree, reaching almost 5000 years old, and the article confirms this. But this news story describes a supposedly 13,000 year old Palmer oak. What's going on? Is the oak part of a clonal colony? The article about Palmer oaks doesn't say anything about that, unlike the article about aspens. ~2026-28007-36 (talk) 07:11, 13 May 2026 (UTC)

Part of a clonal colony sounds right. There's this paper. Sean.hoyland (talk) 07:29, 13 May 2026 (UTC)

Yes. It's mentioned in the Palmer oak article, with a link to Jurupa Oak, the individual tree (colony).  Card Zero  (talk) 08:50, 13 May 2026 (UTC)

The second paragraph of Quercus palmeri#Description says precisely that:

"Quercus palmeri usually grows in small populations, some of which are actually all clones of a single plant. One such clone in the Jurupa Mountains in Riverside County, California, named the Jurupa Oak, was determined to be over 13,000 years old, a single individual living as a relict from the Pleistocene. It is therefore one of the oldest living plants in the world."

{The poster formerly known as 87.81.230.195} ~2026-27434-43 (talk) 15:05, 13 May 2026 (UTC)

FWIW the sole surviving clonal colony of the shrub Lomatia tasmanica in Tasmania is estimated to be at least 43,600 years old. Shantavira|^{feed me} 08:39, 15 May 2026 (UTC)

I think with vegetative clonal entities we start to run into ambiguosities when we think about "a tree" and its "age" as if these mean the same as for a plant such a bristlecone pine that reproduces sexually and is definitively made up of single individuals.

As a related question, what is the "age" of a single-celled organism such as an amoeba that reproduces by binary fission? When it does, do we have two individuals with the same age as previously, or one 'older' original and one 'younger' with no easy way to decide which is which (though there is sometimes a slight difference) or two new individuals of zero age? If the first of these, is that age effectively the age of the species, which may be measured in millions of years? {The poster formerly known as 87.81.230.195} ~2026-27434-43 (talk) 05:23, 17 May 2026 (UTC)

May 17

Looking for examples for use at WP:YWAB

At WP:YWAB I have a bunch of examples of mainstream and fringe topics such as geology vs. flood geology and Holocaust studies vs. Holocaust denial.

I would like to add a note about topics that are not clearly fringe and not clearly accepted science, such as Ball Lightning or The Hum. I am having trouble thinking of good examples that are familiar to most readers. I was thinking earthquake light but that article is seeing a lot of disruption by a fringe pusher. Can anyone think of any good examples? And what should I call them? Unsolved mysteries? --Guy Macon (talk) 05:56, 17 May 2026 (UTC)

For weird stuff see List of unexplained sounds and Bloop. In general Category:Unexplained phenomena covers a lot of phenomena, though some are already explained, like Paulding Light. Things a bit outside science could be Ghost hunting, Cryptozoology. Stuff that is currently in science but I think is dubious: Dark matter, Dark energy, String theory. Graeme Bartlett (talk) 08:06, 17 May 2026 (UTC)

Forteana? Or anomalous phenomena perhaps.  Card Zero  (talk) 08:46, 17 May 2026 (UTC)

Found another: Star jelly.

Bloop is certainly an anomalous phenomena, but unlike earthquake lights we don't have skeptics arguing the the bloop never happened, just scientists wondering what caused it. Should that be what I am looking for when I put together my "somewhere between fringe and mainstream" list? Or should I limit myself to things that might not even exist, like lights generated by earthquakes?

Dark matter is perfect: "an invisible and hypothetical form of matter". Is the evidence for Dark Energy any better? Our articles on the two sure make it look that way.

Ghost hunting and Cryptozoology are pure fringe/pseudoscience. Not what I am looking for.

Has anyone seriously claimed that a String (physics) (or better yet, a Brane) is an actual physical object that we can examine, like we can with a Black hole? --Guy Macon (talk) 12:11, 17 May 2026 (UTC)

Heinrich Schliemann discovered, or uncovered, and to some extent assembled, the legendary city of Troy, when he dug straight through it, and he unscientifically misidentified "Priam's Treasure" as belonging to King Priam, because he wanted his woo-woo theory to be true. By accident, it was true, except in all the details.  Card Zero  (talk) 15:00, 17 May 2026 (UTC)

That's some fine sciencing there, Heinrich. --Guy Macon (talk) 16:13, 17 May 2026 (UTC)

Dark matter and energy are both utterly and absolutely mainstream physics. Even though we can't directly observe them, their existence is considered very well supported by the evidence. Questioning their existence is more likely to be considered fringe by scientists. The meaning of "hypothesis" and "hypothetical" in science is in no way equivalent to "fictional".

String theory and branes are also taken seriously and considered legitimate hypotheses in mainstream physics, even if considered to be backed by less evidence so far than dark matter/energy have. From what I understand, string theory is now considered less likely to be true than it was a decade or two ago, as experiments have ruled out certain versions, but it's in no way fringe.

None of these are pseudoscience. None are considered remotely as questionable by physicists as flood geology is by geologists. They'd be very poor candidates for "we're biased against theories that are contradicted by evidence". -- Avocado (talk) 00:31, 18 May 2026 (UTC)

There is a long-standing debate whether it is justified to position string theory within the scope of the natural sciences, as it does not follow the paradigm of the scientific method. It is comfortable as a mathematical theory, just like braid theory and sheaf theory. These names use a different sense of the term theory. String theory can also be positioned in the scope of "speculative physics", which is not essentially different from rock-hard science fiction.  ​‑‑Lambiam 09:01, 19 May 2026 (UTC)

Quantum field theory is also a theory. And large swaths of modern physics are basically math. That doesn't change the fact that the bulk of real physicists take both QFT and string theory seriously -- including those who don't think string theory is correct. String theory is widely studied in academia. It's published in major, respectable scientific journals. Some of its predictions have been tested empirically at the LHC and certain classes of it ruled out by the scientific method. People get degrees for studying it and spend their lives working on it at highly regarded physics departments of universities around the world.

It's certainly not proven. Intelligent and educated people can believe it to be false without their stance being antiscientific. But it's not something that the vast majority of serious scholars in the broader field it's a part of scoff at as ridiculous or dismiss as unscientific, the way you would get a consensus of geologists that "flood geology" is absurd. It's not at all in the same category as Holocaust denial or Atlantis or astrology or phrenology as something that Wikipedia should be "biased against" because it's contradicted by the evidence. And if you don't believe me (I'm certainly not a physicist myself, just an interested layperson who tries to pay attention to what the actual scientists are saying), I'm sure there's a consensus to be reached one way or another over at WP:Physics. -- Avocado (talk) 10:53, 19 May 2026 (UTC)

Quantum field theory has stood its ground – actually exceptionally well – in making predictions that were experimentally confirmed. Arthur Eddington had a theory about fundamental dimensionless physical constants being algebraic numbers. A theory, perhaps. A scientific theory, not. String theory, as a theory about physical reality, does not have a better track record. The fact that it is studied around the world by respected scientists does not make it more scientific than it is.  ​‑‑Lambiam 06:56, 20 May 2026 (UTC)

You and I are clearly not going to convince one another to change our minds about the status of stringy theory as a theory. But do you really believe it should be bucketed with astrology as something that Wikipedia is "biased against"? -- Avocado (talk) 11:37, 20 May 2026 (UTC)

There is also a range of medical treatments that will span a spectrum from well proven to alternative, to fringe, to totally bogus. Stuff outside science may be in Alternative medicine. Stuff in the unclear area might be aromatherapy, red light therapy, Chiropractic. Some recent treatments for alzheimer's are claimed to be scientific, but are dubious money makers for some drug companies. Graeme Bartlett (talk) 00:39, 19 May 2026 (UTC)

Thanks! Good suggestions. In particular, take a look at [ https://www.amazon.com/s?k=red+light+therapy ]. Lots of money being made there -- stringing together a bunch of red LEDs is pretty cheap. Alas, I don't seem to qualify. Looking at Amazon, the treatments seems to only be for scantily clad females... --Guy Macon (talk) 12:34, 19 May 2026 (UTC)

May 18

Wine

Why is most wine 12.5% ABV? Martinevans123 (talk) 18:57, 18 May 2026 (UTC)

Above that, alcohol kills yeast. --jpgordon^{𝄢𝄆𝄐𝄇} 19:27, 18 May 2026 (UTC)

Thanks. But some wines (only reds?) can be 13% - 15%? Martinevans123 (talk) 19:48, 18 May 2026 (UTC)

My answer was overly simple. It's also a function of how much sugar is in the grapes in the first place, and which yeast is being used. --jpgordon^{𝄢𝄆𝄐𝄇} 20:33, 18 May 2026 (UTC)

Also, the vintner can adjust a wine's strength by blending and dilution, and may want to tailor the strength to keep it consistent from year to year, and to target a particular market. {The poster formerly known as 87.81.230.195} ~2026-27434-43 (talk) 23:31, 18 May 2026 (UTC)

Well, it isn't. Some are 11, but the vast majority of Australian reds I buy are 13-14%. They are mostly shiraz or <late edit cabinet> cabernet from the south, not (in theory) the Murray which is where the volume grapes are grown. In practice many boutique vineyards blend in some of high sugar content grapes, rather like the French used to with Algerian wines. Whites are in the 13-14.5% range, I like heavy chardonnays. If you look for sherry style white wines they can hit 16% with no fortification, such as Montilla, and I think some Australian sherry style finos hit that with no fortification as well. In general the cheap wines tend to have lower ABV so as to keep the shelf price down. Greglocock (talk) 23:34, 18 May 2026 (UTC)

Thanks for the additional detail. Maybe more needs to be added at Winemaking#Crushing and primary (alcoholic) fermentation. It currently just says "Alcohol of more than 12% can be achieved by using yeast that can withstand high alcohol. Some yeasts can produce 18% alcohol in the wine however extra sugar is added to produce a high alcohol content." I'm aware that sherry is a very different thing (... and I remember frequenting Yates Wine Lodge in Nottingham...) I wonder how one would discover the proportions of wines at a given ABV across the world? Thanks. Martinevans123 (talk) 07:21, 19 May 2026 (UTC)

This seems like a decent place to start, though it's not a direct answer to your question. The base data seems to only get down to the white/red split, not the individual breakdowns by ABV segment. Matt Deres (talk) 16:46, 19 May 2026 (UTC)

Thanks, that's very interesting. Martinevans123 (talk) 16:48, 19 May 2026 (UTC)

User:Greglocock, do you keep your cabinets in the cabernet? :) -- Jack of Oz ^{[pleasantries]} 23:21, 19 May 2026 (UTC)

_{Nah, we're posh. Cardboard box in the garage.} Greglocock (talk) 00:01, 20 May 2026 (UTC)

I don't like heavy wines. A kilo a litre is plenty. DuncanHill (talk) 00:06, 20 May 2026 (UTC)

OH, got it. corrected Greglocock (talk) 00:45, 20 May 2026 (UTC)

Bless you. -- Jack of Oz ^{[pleasantries]} 22:18, 22 May 2026 (UTC)

Locoweed and Datura

Our article on locoweed claims that it is incorrect to refer to Datura species as locoweed. The claim has a source but the source does not say it is incorrect; instead, it says that Datura is locoweed.

I had always thought of locoweed as referring to Datura. Does anyone have knowledge and sources to clarify the issue? --Trovatore (talk) 22:55, 18 May 2026 (UTC)

I think our article is using the source as an example of incorrect use. Really it is a bad reference as you say. Also it is user generated content, and so classed as unreliable. Graeme Bartlett (talk) 00:44, 19 May 2026 (UTC)

Yes, I understood that. My question is, is it actually incorrect? I had always thought of locoweed as meaning Datura. --Trovatore (talk) 05:41, 19 May 2026 (UTC)

For a descriptivist, there is no such thing as "actually" incorrect. The term locoweed is not a term of art. Quoting Datura stramonium § Etymology and common names:

"Common names for Datura stramonium vary by region and include thornapple, [...], locoweed, [...], and devil's cucumber."

Datura ceratocaula is called "torna-loca" ("goes crazy") in Mexico.

In veterinary use, the term locoweed is used primarily in connection with the cause of locoism, livestock gradually getting poisoned by chronically ingesting swainsonine-producing plants. The deliriant effect on livestock from ingesting scopolamine-producing plants such as Datura species is AFAIK not referred to as "locoism".  ​‑‑Lambiam 08:28, 19 May 2026 (UTC)

The OED gives two meaning for "locoweed". The first is "loco", meaning "Any of several leguminous plants of either of the closely related genera Astragalus and Oxytropis (both of the subfamily Faboideae) found in the western and south-western United States" (which it then associates with loco disease, and the second "Originally and chiefly North American slang.= marijuana". DuncanHill (talk) 00:13, 20 May 2026 (UTC)

All these senses can be found at Locoweed (disambiguation).  ​‑‑Lambiam 08:45, 20 May 2026 (UTC)

Not the last one. Matt Deres (talk) 12:22, 20 May 2026 (UTC)

If you mean the "marijuana" one, it's on the dab page as Cannabis. Deor (talk) 12:49, 20 May 2026 (UTC)

May 20

Zinc acetate decomposition

Hi! I am a very amateur chemist and I've been trying to synthesize zinc acetate by the addition of vinegar to a strip of zinc metal, and evaporating the vinegar by letting it sit in air. I am able to produce white crystals that I believe to be zinc acetate, but after a few days of letting them sit out, they have turned orange. The orange color seems to disappear (or rather become very diluted) upon re-adding vinegar. What could be causing this orange color, and how could I figure out what the product is?

Previous tests indicate the solubility of the orange product is 8 g/100 mL.

I suspect the product to be basic zinc acetate but I cannot corroborate this with online sources as they do not provide info on basic zinc acetate's color or solubility.

UnbihexiumFan (talk | contribs) 15:47, 20 May 2026 (UTC)

Sounds like Zincite. Did some iron get involved maybe?  Card Zero  (talk) 17:09, 20 May 2026 (UTC)

Probably not zincite, as it's a form of zinc oxide which has a much lower solubility. I don't think there's any source of iron so I don't know how it would get there. I also don't know why the color would only appear on prolonged standing if it was iron, leading me to suspect it is a colored zinc compound. Not sure what it would be though, and I'm not sure how I would identify the product.

Regarding the AI response below, all the compounds listed are very insoluble in water, so it can't be any of those.

I'm really regretting not running solubility tests immediately after precipitation... but I can probably isolate more of the white crystals before they decompose and test that.

UnbihexiumFan (talk | contribs) 22:53, 20 May 2026 (UTC)

An AI response The following discussion has been closed. Please do not modify it.

This response with references was given by CoPilot on May 20th 2026 Your orange discoloration is almost certainly iron contamination forming iron(III) acetate or mixed basic iron salts, not a zinc compound. This matches the suggestion in the thread that it “sounds like zincite,” but zincite is ZnO and yellow, not orange — the color points much more strongly to Fe³⁺ compounds.

The fact that the orange color disappears when you add vinegar again is a key diagnostic clue: iron(III) hydroxides/oxides dissolve in acetic acid, forming pale yellow iron(III) acetate complexes.

Why this happens When you dissolve zinc metal in vinegar:

Zn + 2   CH₃COOH → Zn(CH₃COO)₂ + H₂ But unless your zinc is very pure, it usually contains iron impurities. Also, if you used steel tools, a steel container, or even tap water, Fe²⁺/Fe³⁺ can enter the solution.

When the solution evaporates, the pH rises and iron(III) precipitates as:

FeO(OH) (yellow–orange)

Fe₂O₃·H₂O (orange–brown)

basic iron(III) acetate (orange)

All of these are orange solids with solubilities in the range of a few g/100 mL — matching your observation of ~8 g/100 mL.

Why adding vinegar removes the color Acetic acid converts the insoluble iron(III) hydroxides/oxides into soluble iron(III) acetate:

FeO(OH) + 3   CH₃COOH → Fe(CH₃COO)₃ + 2   H₂O Iron(III) acetate is pale yellow, so the strong orange color disappears.

Is it basic zinc acetate? Unlikely. Basic zinc acetates are white or colorless, and no known zinc acetate species is orange. The color is diagnostic for iron.

How to confirm experimentally Here are simple, safe tests you can do at home:

1. Magnet test Dry the orange powder and bring a strong magnet near it. If it contains iron oxides/hydroxides, you may see slight attraction.

2. Potassium thiocyanate test (if available) Add a drop of KSCN to a small sample dissolved in vinegar. A blood‑red color confirms Fe³⁺.

3. Ammonia test Add household ammonia to a small amount of the orange solid in water:

Rusty orange precipitate → Fe(OH)₃

White precipitate → Zn(OH)₂

4. Flame test Zinc gives no characteristic flame color. Iron contamination may give a golden spark effect.

References Here are authoritative sources confirming the chemistry:

Iron(III) hydroxide/oxide colors: orange–brown (standard inorganic chemistry texts)

Iron(III) acetate is yellow–brown and forms from Fe³⁺ + acetate Greenwood & Earnshaw, “Chemistry of the Elements,” 2nd ed.

Zinc acetate and basic zinc acetates are white CRC Handbook of Chemistry and Physics

Iron impurities in zinc metal are common and dissolve during acid attack Vogel’s Qualitative Inorganic Analysis

Is your vinegar pure acetic acid in water? Spirit vinegar or industrially produced acetic acid should be purer than fermented products that may have extra brown coloured content when they dry out. Based on Zinc acetate you may have produced the dihydrate. Graeme Bartlett (talk) 01:03, 21 May 2026 (UTC)

Store bought white vinegar.

Zinc acetate dihydrate is probably the initial product of course, but there's likely something going on that turns it orange upon aging. I've observed this in multiple samples, and at first I thought it was due to me adding isopropyl alcohol in a futile attempt to extract Zn acetate from the solution, but clearly the same is happening w/o isopropyl alcohol. What impurities in vinegar would cause the discoloration?

UnbihexiumFan (talk | contribs) 02:10, 21 May 2026 (UTC)

I wonder if the impurities in the vinegar have accidentally created a lake pigment with the zinc cation. Mike Turnbull (talk) 15:53, 22 May 2026 (UTC)

What kinds of impurities would be in my vinegar?

UnbihexiumFan (talk | contribs) 16:04, 22 May 2026 (UTC)

May 22

Alternatives to fuel

As we have bikes and buses running on rechargeable large battery, can planes fly without fuel? Big planes like Boeing in future?

Induction cooker takes lots of time to cook compared to fuel. Will any alternative exist for cooking where one don't need to purchase fuel?

https://www.theguardian.com/environment/2026/apr/24/global-oil-crisis-changed-fossil-fuel-industry-for-ever-iea-chief-fatih-birol

https://www.ft.com/content/f3034a00-2ea3-4aa0-aab3-ba0d48af4048?syn-25a6b1a6=1 ~2026-30783-03 (talk) 10:45, 22 May 2026 (UTC)

Hmm, not really. Small planes that use batteries can fly for an hour or so, but long range is unlikely if you want a decent payload. Greglocock (talk) 11:40, 22 May 2026 (UTC)

You mention bikes. The first aircraft was pedal-powered, built by two bicycle builders. It couldn't fly. They strapped a gas-powered engine to it just to get it to fly a short distance.

Then, you mention buses. Modern commercial aircraft is essentially a bus with wings. That is the point - get as many people from point A to point B as possible with the least amount of resources spent.

Flying without fuel implies you are referring to electric. All-electric vehicles use either a very long power cable or batteries (or both). It is not reasonable to run power lines through the sky for planes to slide on. Batteries are required. From this point, it all about the potential energy. Avoiding the physics notation, let's put it like this: If you had a milk jug full of fuel, you could take off in a small plane, circle, and land, and likely have some fuel left over. To do that with batteries, you would have nearly 100 pounds of batteries, basically a second passenger. For a commercial aircraft, the battery would take up the entire aircraft. There would be no room for passengers or baggage. Yes, batteries are getting smaller and lighter, but this isn't an issue of making them 10% better. We need to make then over 1,000% better. So, that isn't the plan.

The plan that is common is to switch fuels. For example, we could switch to hydrogen fuel. We could use nuclear fuel. It is possible that future aircraft will fly for hours on a pebble-sized fusion fusion fuel source. Or, we might have a massive leap in technology and suddenly people can just teleport anywhere they want to go. Of course, what fuels those teleporters? A Hemi V8? ~2026-16820-81 (talk) 11:55, 22 May 2026 (UTC)

There is the solar cooker. The fuel is billions of tons of hydrogen 93 million miles away, but there is no charge. -- Verbarson  ^talk_edits 14:23, 22 May 2026 (UTC)

The first aircraft was pedal-powered, built by two bicycle builders. It couldn't fly. Where on earth did you get this nonsense from? At no point did the Wright brothers ever construct a pedal-powered aircraft. AndyTheGrump (talk) 14:43, 22 May 2026 (UTC)

@~2026-30783-03 Wikipedia has many articles in Category:Electric_aircraft. They use energy from many conventional sources to generate the electricity to charge the batteries when on the ground. To take just one example, see Beta Technologies Alia. Mike Turnbull (talk) 15:44, 22 May 2026 (UTC)

There's a theoretical limit to the energy density of batteries. There's still room for improvement, but not enough for long range flight. Trains are usually electric, electric buses are common, although those on battery power do suffer from high mass, even electric boats exist, but electric aeroplanes for anything more than really short hops seem unlikely. For the record: my bike is still 100% muscle-powered.

And induction cooking works just fine, assuming your electric service connection was designed for it. Just as responsive and fast as natural gas and without the indoors NOx emission. I switched from natural gas to induction a few years ago; wouldn't want to go back. Other forms of electric cooking are worse though. PiusImpavidus (talk) 18:07, 22 May 2026 (UTC)

To add a formula (this is the science desk, after all), the range of a battery powered aeroplane is approximately

$R=e\cdot B\cdot \eta \cdot \rho _{L/D}/g$

with $R$ the range, $e$ the specific energy of the batteries, $B$ the fraction of the aeroplane's loaded weight devoted to batteries, $\eta$ the efficiency of the propulsion system, $\rho _{L/D}$ the lift-to-drag ratio and $g$ the acceleration of gravity. You need some more energy to climb, but you get it back on descend. Current electric aeroplanes have a range of a few tens of kilometres. An airliner needs a range of around a thousand kilometres at least, so one has to gain about a factor of 30. $e$ can be improved, but not that much. $B$ and $\eta$ are already a significant fraction of 1 and can't be more than that. $\rho _{L/D}$ is about 16–20 for modern jet airliners and around 60 for gliders, so there's some room for improvement, but only if one accepts small aeroplanes with huge wingspan, cruising well below transonic speed. In other words, too short range for transoceanic flight and too slow to compete against land transport. There may be a role for electric aeroplanes in bush flying and island hopping.

Note that the size of the aeroplane doesn't show up in the formula, other than larger aeroplanes having a tendency to lower $\rho _{L/D}$. This is partly because they may have undersized wings to fit at the gates of an airport, partly because bigger aeroplanes need to go faster and their $\rho _{L/D}$ drops when going transonic. We could build an electric airliner the size of an A320 right now, but it would have a range less than 100 km, which it would cover in 15 minutes or so. PiusImpavidus (talk) 10:49, 23 May 2026 (UTC)

The Alia is designed to charge in under an hour, and carry five passengers or cargo for up to 250 nmi (460 km; 290 mi). Not all useful aircraft have to have "a range of around a thousand kilometres at least". Mike Turnbull (talk) 11:22, 23 May 2026 (UTC)

You say "$e$ can be improved, but not that much", but then I compare Lithium-ion battery (Specific energy up to 450 W⋅h/kg) to Lithium–air battery (Specific energy 11,140 W⋅h/kg theoretical). What's up with that?  Card Zero  (talk) 12:07, 23 May 2026 (UTC)

See Comparison of commercial battery types. Look at the energy density by mass. Our Lithium–air battery article doesn't list energy density by mass for the simple reason that they don't exist except as laboratory curiosities.

BTW, here is an electric aircraft that can stay in the air indefinitely without running out of juice: Petróczy-Kármán-Žurovec#PKZ-1 --Guy Macon (talk) 18:02, 23 May 2026 (UTC)

But if this is about "a theoretical limit to the energy density of batteries", the theoretical room for improvement does appear to be enough for long range flight, using batteries that are full of implementation problems and therefore don't exist, but theoretically could.  Card Zero  (talk) 19:36, 23 May 2026 (UTC)

Electric stoves and electric ovens are also a thing, and have been since before WWII, independent of induction cooking -- though a lot of cooks don't like the experience of electric cooktops all that much.

The issue with aircraft is that batteries are a lot heavier per unit of energy than carbon-based fuels. That extra weight causes them to need more energy to fly the same distance, which in turn means a bigger, heavier battery. It would take massive advances in battery technology to make them commercially viable. -- Avocado (talk) 21:04, 22 May 2026 (UTC)

What makes it even worse is that, in contrast to jet fuel, you still have to carry the batteries after they've been depleted. The raw materials are too valuable to just dump them – in addition to the safety and environmental concerns. PiusImpavidus (talk) 09:57, 23 May 2026 (UTC)

Makes me think of some sort of absurd scheme where warehouses are dotted all over the world and they attach the batteries to hang-glider drones that can guide them to warehouses when the flight path passes close enough for the drone to make it to the warehouse with a depleted battery. Wouldn't work so well for really long flights across the Pacific Ocean, unless you detoured close enough to those few scattered islands, though, I suppose. And then you'd need a whole supply chain to ship them back to the major airports. Fun to think about, though! -- Avocado (talk) 13:52, 23 May 2026 (UTC)

Electricity can be transported using these amazing things called wires. Don't need a tanker or drones. NadVolum (talk) 16:18, 23 May 2026 (UTC)

I don't know that I've ever even visited a house with a gas stove. Are electric ranges really that rare outside the US?--User:Khajidha (talk) (contributions) 15:18, 23 May 2026 (UTC)

In the UK it's split about evenly, with electric now being somewhaty more common for ovens and gas still slightly more common for hobs (stove tops); gas used to be more common overall, and older people tend to prefer it because they're so used to it, because it's a little quicker to adjust, and because the flame is actually visible so one can see the adjustment directly. Electric has the advantage of not in itself causing condensation, a significant consideration in colder, damper Britain where houses are often not well ventilated. {The poster formerly known as 87.81.230.195} ~2026-27434-43 (talk) 15:40, 23 May 2026 (UTC)

Electric is rare even in certain parts of the US, fwiw -- especially older cities that were plumbed for gas transmission for heating and light in the 19th and early 20th centuries. I've really only encountered electric in suburbs, though induction is gradually making inroads, especially with new regulations in some places forbidding the installation or replacement of gas stoves. -- Avocado (talk) 16:54, 23 May 2026 (UTC)