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Wikipedia:Reference desk/Archives/Science/2016 April 2

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April 2

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Book recommendations on the history of automotive engines

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Hello, Science Reference Desk. I am looking for recommendations on full-length, non-fiction books (or equivalently-detailed internet resources) that review the modern history of automobile engines. I'm looking for a book that goes into considerable depth beyond our articles. For context, this query is prompted by some extensive reading I have already conducted; I've absorbed about everything I can from our articles... This morning on BBC World Service radio, I learned that after switching to 1.6 liter, six cylinder turbocharged hybrid engines, Formula 1 cars are now completing laps faster than when they used ten cylinder, 3.0 liter BMW engines just a few years ago (interview paraphrased in the web news story). This progress seems incredible, and it's no surprise that it's flared some brand rivalry! I'm trying to determine whether these technology results are representative of progress across the entire automotive industry, or if F-1 engines have evolved so far out on their own branch of the technology tree that these improvements cannot translate to ordinary cars - (needless to say, turbo-compound engines used in these racecars look an awful lot like turbocharged aircraft engines!); or if the new race results are consequences of other changes independent of engine performance. Nimur (talk) 16:34, 2 April 2016 (UTC)[reply]

doubt you'll find a full-length general interest book specifically about what you're looking for....vaguely related though: this is among the greatest (and best-selling) pop autobiographies ever written and about American auto industry...has all kinds of cool stuff about the creation of the Ford Mustang.. Iacocca: An Autobiography 68.48.241.158 (talk) 19:14, 2 April 2016 (UTC)[reply]
I'd second that. It generally takes a while to get good technical books about motor sport, so I don't believe there is detailed information about the latest engines in book form. If you were to buy Autocourse from the last few years, you could start to read some of it. The other issue you'll face is that F1 isn't just about engine power: aerodynamics have a huge part to play, and the influence of changing regulations on the amount of aerodynamic assistance makes a huge effect on lap times. For example, the Coandă effect had a huge influence on F1 design a few years ago, but is pretty much outlawed now. Also, note that unrestricted 1.6 turbo engines would blow 3 litre NA engines into the weeds: in the 1980s both were allowed: the 3L engines produced 5-600 BHP; the 1.5L turbos knocked out well over 1000 BHP in qualifying form. And a final comment: the F1 fraternity does not refer to the current generation as the "engine": they are power plants, comprising an internal combustion engine, a turbo with a heat recovery system (MGU-H) and a kinetic recovery system (MGU-K) with a battery storage system and an electric power unit to boost output. If you read in places like https://www.formula1.com/ some of this will be covered.--Phil Holmes (talk) 19:29, 2 April 2016 (UTC)[reply]
Indeed, thank you for the terminology correction! Nimur (talk) 15:25, 3 April 2016 (UTC)[reply]
You might want to try a magazine like Popular Mechanics. While not exclusively devoted to car engines, I bet they go into more detail than car magazines, which tend to be very superficial on mechanical details. If you go to a library with those in stock, you can probably find quite a bit of detail on car engines found in issues over the decades. StuRat (talk) 19:25, 2 April 2016 (UTC)[reply]
Cough. I'd be a little surprised if Popular Mechanics covered the design parameters of Formula One systems pushing out around 900 BHP from 1.6L power plants. They tend not to be home maintenance projects. The estimate from Bernie Ecclestone today was that Mercedes-Benz spent around $700M developing theirs, so it's a bit more than a garage project.--Phil Holmes (talk) 20:55, 2 April 2016 (UTC)[reply]
For Formula One, yes, it's uber advanced, everything custom. Other racing classes can be done in one's garage, one of my neighbors was a race car driver and was always working on his race car. Engines have improved tremendously over the course of my life, with increasing compression, greater efficiency and even transmissions being more efficient in using the energy the engine delivers to them. I wonder at times, just what will the next half century bring?Wzrd1 (talk) 20:59, 2 April 2016 (UTC)[reply]
Thanks guys. Nimur (talk) 13:56, 3 April 2016 (UTC)[reply]

Do bacterium have feelings/aspirations?

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Lets take paramecium for example. Does paramecium have feelings, such as happiness and sadness? Moreover, how do they know what they are doing? Surely they must have aspirations, such as "I must eat 6 pieces of algae today and then reproduce". --FallinggoApartio (talk) 19:51, 2 April 2016 (UTC)[reply]

Did you mean to post this yesterday? DrChrissy (talk) 19:54, 2 April 2016 (UTC)[reply]
No. That would require nerve cells and a brain. Think of a computer program, does it have feelings and aspirations, or does it just do what it is programmed to do, without any thought at all ? StuRat (talk) 19:54, 2 April 2016 (UTC)[reply]
StuRat, be careful what you assume to require nerve cells and a brain. Some organisms can surprise you.
"Studies on Physarum have even shown an ability to learn and predict periodic unfavorable conditions in laboratory experiments. Professor John Tyler Bonner, who has spent a lifetime studying slime molds argues that they are "no more than a bag of amoebae encased in a thin slime sheath, yet they manage to have various behaviours that are equal to those of animals who possess muscles and nerves with ganglia – that is, simple brains." --Slime mold#Behavior
--Guy Macon (talk) 06:13, 3 April 2016 (UTC)[reply]

Ultimately there is no way to know whether a paramecium has subjective experience, aka qualia. That's what makes it subjective. But it does seem unlikely. --Trovatore (talk) 19:58, 2 April 2016 (UTC)[reply]
If you're a materialist I think it's pretty safe to say that single-celled organisms don't have "feelings" or mental "experiences", any more than your skin cells do. Thought requires a brain. --71.110.8.102 (talk) 22:14, 2 April 2016 (UTC)[reply]
Yes, materialists would say that, that's true. However materialists really cannot explain the hard problem of consciousness. The extremists among them, the "eliminative materialists", simply deny that it's a problem. --Trovatore (talk) 22:44, 2 April 2016 (UTC)[reply]
Given what we know about qualia (nothing), I see absolutely no reason to think that single-celled organisms don't (or do) have qualia, whether or not you're a "materialist". -- BenRG (talk) 04:00, 3 April 2016 (UTC)[reply]
They respond to stimuli. Maybe between stimulus and response there are intermediate states that, once we've figured out what qualia are, we'll recognize as qualia. Maybe not. -- BenRG (talk) 04:00, 3 April 2016 (UTC)[reply]
"Paramecium lack"??? I'm almost used to seeing "bacteria" used as a singular noun, but "paramecium" as a plural is new to me. --Trovatore (talk) 04:06, 3 April 2016 (UTC) [reply]

Sedan vs. Hatchback

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What advantages do sedans have over hatchbacks? Is it just a question of aesthetics? --Llaanngg (talk) 20:41, 2 April 2016 (UTC)[reply]

Hatchbacks potentially allow for more storage space than a sedan, given the large hatch access to the storage area and the two-box design that merges passenger and cargo compartments. clpo13(talk) 20:52, 2 April 2016 (UTC)[reply]
I think you read the Q backwards, he was asking for advantages of the sedan. StuRat (talk) 21:00, 2 April 2016 (UTC)[reply]
Whoops, you're right. Dunno what I was thinking. clpo13(talk) 21:03, 2 April 2016 (UTC)[reply]
Disadvantages of hatchbacks:
1) They get hot, due to all that extra window surface area, and it being more horizontal than in a sedan. (Could be an advantage in winter, if not covered in snow.) I had a game melt back there (King Oil). Louvers can help here, but they impair visibility somewhat.
2) The contents of the cargo area can be seen, both looking messier and tempting thieves. There can be some type of cover used to prevent this.
3) The opening height can be higher, and the hatch heavier, making it harder for short people to close the hatch.
4) The pneumatic(?) cylinders that hold them open can fail, and if the hatch falls on your head, it could cause serious injury.
5) Smells in the hatch area intrude on the passengers more. Imagine a bag of manure.
6) More window area to clear of ice in winter.
7) The more horizontal hatch is more likely to shatter in a hail storm. StuRat (talk) 21:00, 2 April 2016 (UTC)[reply]
What hatches have a more horizontal rear window than a sedan? Iapetus (talk) 13:55, 4 April 2016 (UTC)[reply]
Hyundai Accent, for one. Compare that with sedans, many of which have a nearly vertical rear window. StuRat (talk) 14:51, 4 April 2016 (UTC)[reply]
Interesting - in the UK, it seems that most sedans (or saloons, to use the local term) have much more inclined rear windows. (From personal observations, I'd say typically about 40-50 degrees. These images seem to support that). Iapetus (talk) 17:05, 7 April 2016 (UTC)[reply]
That's two sedans you compare. This is the hatchback version:
Thanks, removed Hyundai Accent Sedan to avoid confusion. The spoiler on the top looks like it would help protect the rear windshield from hail. StuRat (talk) 15:25, 4 April 2016 (UTC)[reply]
That's the point, StuRat. I wanted to know why would someone prefer a sedan. I could only think about advantages of hatchbacks over sedans, like the example above your answer. They also have a bigger trunk lid for bulky objects. In a sedan, even if you had space for a fridge, you won't get into the trunk. Llaanngg (talk) 21:02, 2 April 2016 (UTC)[reply]
Safety could also be an issue. Sedans might have the center of gravity lower than a hatchback. Scicurious (talk) 21:10, 2 April 2016 (UTC)[reply]
And if you get rear-ended, the trunk can collapse and provide more protection. This paper only mentions that the car is more likely to remain driveable, but presumably there is some safety benefit for occupants as well. --69.159.61.172 (talk) 21:15, 2 April 2016 (UTC)[reply]

1 Aesthetics maybe

2 Weight, that side glass weighs, as does the ring bulkhead for the tailgate

3 CGZ

4 Body torsional stiffness

5 squeaks and rattles

6 temperature control

7 tailpipe emission ingress

8 tailpipe noise ingress

That list is definitely the sound of straws being grasped, the differences are slight and the practicalities favor the hatch for most people I'd have thunk. In India hatchbacks are lower status than sedans, hence the wide availability of models that would be hatchbacks anywhere else with a funny little bustle trunk. Greglocock (talk) 22:43, 2 April 2016 (UTC)[reply]

CGZ?Scicurious (talk) 22:47, 2 April 2016 (UTC)[reply]
Higher Center of Gravity in the Z (vertical) direction. StuRat (talk) 22:49, 2 April 2016 (UTC)[reply]
Yeah, that accident at CGZ? Caused by a hatchback. The more you know ====* clpo13(talk) 22:51, 2 April 2016 (UTC)[reply]
  • Other than style, the only disadvantage they list is that potential thieves can view what's in the back. That's my point #2. I also notice that Greg's unreferenced list and Scur's unrefed response got no criticism from you, showing you are on a one-man vendetta against me. Should you really bring your personal grudges here ? Or can you just list your refs without the personal attack next time ? StuRat (talk) 07:10, 3 April 2016 (UTC)[reply]
It's difficult to find objective information on this subject, but there's this post on Reddit where someone has at least gone to the trouble of collating a number of responses to find the most popular features of sedans. To summarise, the top advantages were (i) looks, (ii) price, (iii) availability, (iv) trunk security and (v) acoustics. --Heron (talk) 09:07, 3 April 2016 (UTC)[reply]
Following up on the security issue, which surprises me ... in the UK every hatchback that I have used has had a rigid horizontal parcel shelf which conceals the contents of the boot/trunk/cargo area when the rear hatch is closed. The parcel shelf can be removed to maximise carrying space, but this would be a temporary measure for a specific purpose. Are parcel shelves not standard equipment on US hatchbacks ? Gandalf61 (talk) 12:28, 3 April 2016 (UTC)[reply]
Parcel shelves in hatchbacks are often inadequate or unsafe for heavy parcels. The Toyota Prius has no shelf, only a thin retractable plastic roller blind. AllBestFaith (talk) 14:42, 3 April 2016 (UTC)[reply]
Yep, that's the same down here (Poland), and as far as I remember, in Western Europe that's also the case. Unless the owner removed it for whatever reason, they all seem to have. It seems to be not only a case of security against thieves, but it's also about safety, to maintain the cargo in place in case of a rollover accident. Llaanngg (talk) 14:47, 3 April 2016 (UTC)[reply]
Benefits of the hatchback is storage and storage with open hatch when demanded. The closed hatch can give an aerodynamic benefit. Many sedans can not flip the passenger seats to use it as storage. Hatchback and sedans differ also in the static structure of the body. Some can not offer a large and low door step. Some shorter hatchbacks offer large doors like customs, some longer doors are narrow, but offer a lower step. This is neccessary when the roof ends more far than on customs and the passenger seats can not stabilize the car body when flipable. --Hans Haase (有问题吗) 09:01, 7 April 2016 (UTC)[reply]

Do we use the calories in alcohol as energy?

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Do we transform the energy contained in alcohol as energy? Could we keep alive longer drinking alcoholic beverages like vodka instead of just drinking water? --Scicurious (talk) 21:07, 2 April 2016 (UTC)[reply]

Yes we use it as energy, but no, you can't stay alive on ethanol alone, as we need many other nutrients. StuRat (talk) 21:09, 2 April 2016 (UTC)[reply]
I don't mean staying alive on ethanol alone. But given the choice to drink just water, or, water and vodka, what would let's use survive for a longer period? --Scicurious (talk) 21:12, 2 April 2016 (UTC)[reply]
That is going to depend on the balance between the water and the vodka. Admittedly the alcohol will have a small nutritional value - but it also has a fairly high toxicity which could cause organ damage if you took too much of it. 217.44.50.87 (talk) 21:33, 2 April 2016 (UTC)[reply]
Also, ethanol causes you to lose more water, as it increases urine production by interfering with vasopressin. So if running out of drinkable water is a problem, best to avoid the liquor. --71.110.8.102 (talk) 22:11, 2 April 2016 (UTC)[reply]
I seem to recall a case of a shipwreck, where they had their cargo of sugar and rum, and fresh water on the island. Some consumed the sugar and rum, while others just drank water, and the latter group lived longer. Not sure if this really happened, and even if it did, they may have died more quickly from overdoing it. A small enough dose of sugar and rum (with water) probably would have been better than water alone. StuRat (talk) 21:53, 2 April 2016 (UTC)[reply]
Do you mean sugar mixed with the rum? Otherwise, I don't see any reason for not drinking water with sugar. --Scicurious (talk) 22:11, 2 April 2016 (UTC)[reply]
No, not mixed. I'm not sure which is worse, sugar-water or rum. StuRat (talk) 23:04, 2 April 2016 (UTC)[reply]
Any citation for this nonsense, Stu?--TMCk (talk) 23:16, 2 April 2016 (UTC)[reply]
I've made no claim that to have stated a fact here, so there's nothing to reference. "I seem to recall..." means I'm not positive. I was hoping somebody else might recognize the story and have the facts. But, since Jayron apparently can't live without endlessly ranting at me, let's let him get his fill. (I was hoping that eventually he would have the sense to keep such rants off the Ref Desk, but alas he doesn't seem to.) StuRat (talk) 07:19, 3 April 2016 (UTC) [reply]
You said "No, do not mix." followed by a false rational and there is no "I seem to recall..." (not that it would matter much). You more than strongly implied the false fact that a sugary soft drink is at least almost as bad as wodka in a survival situation. One can only hope nobody, including youself, remembers and applies your ideas in a lifethreatening situation: "Throw the pop of the raft. The guy from the ref-desk said it could be even worse than wodka."--TMCk (talk) 14:54, 3 April 2016 (UTC)[reply]
I thought he was asking if the rum was already mixed with sugar when they were shipwrecked, and I said "No, not mixed". And the "I'm not sure which is worse, sugar-water or rum" means exactly that, I'm not sure. I'm not implying anything, so please stop reading things into it and only look at what was actually said. The "I seem to recall..." was on my previous reply where I introduced the story. Since all you said was "this nonsense" without saying what you consider to be nonsense, I had no idea what you were complaining about, and thought it might be the entire shipwreck story. If you are going to ask for citations, be specific about what claim you want the citation for. StuRat (talk) 06:23, 4 April 2016 (UTC) [reply]
Have you ever considered using one of those?--TMCk (talk) 14:16, 4 April 2016 (UTC)[reply]
Stu doesn't believe in providing citations for anything he says. He has said so repeatedly in the past. He believes everything he says is so blatantly obviously true, it doesn't need references. Which questions why it needs saying at all, if that were true. However, getting Stu to provide even a single reference to any question he answers is a futile endeavor. He will refuse to do so, and will instead now pick through your personal editing history for the one time you answered a question 3 years ago without a reference, and hold that aloft as why he doesn't have to provide references ever for any of his ridiculous speculations. Then he'll attack you relentlessly for that one answer you gave three years ago, trying to deflect the legitimate criticism against himself for never providing a single reference ever. --Jayron32 03:24, 3 April 2016 (UTC)[reply]
Re: "Stu doesn't believe in providing citations for anything he says", I've provided many refs for questions on this very page, so you are quite obviously lying. StuRat (talk) 07:23, 3 April 2016 (UTC) [reply]
A useful cut-and-paste: [ Citation Needed ]. (Note that it has three links in it, not one.) --Guy Macon (talk) 06:24, 3 April 2016 (UTC)[reply]
Indeed, if everything that you have is water, sugar and rum, I don't see why someone wouldn't take at least some sugar besides water. Maybe he should go lightly with the rum, though. Scicurious (talk) 23:42, 2 April 2016 (UTC)[reply]
And how does the alcohol get digested/converted to energy by our bodies? Alcohol is not present (or only scarcely) in nature, so, why would we be able to process it into energy? Scicurious (talk) 14:40, 3 April 2016 (UTC)[reply]
Good question. One wishes there was an easily available online encyclopedia with an article about the topic. Shock Brigade Harvester Boris (talk) 15:06, 3 April 2016 (UTC)[reply]
As for why, ethanol is harmful if not metabolized, and it may just be an accident that it gets metabolized into a form that provides us with energy. On the other hand, if somewhere in our evolutionary past was an animal that ate rotting fruit, it may have had enough evolutionary pressure to use that energy to develop such a trait, and then passed it down to us. StuRat (talk) 14:33, 4 April 2016 (UTC)[reply]

Stupid cold fusion questions

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These are all vaguely related to muon-catalyzed fusion, a process that would be the end of the energy problem if only muons were more stable...

1. Muon-catalyzed fusion is said to work because the nuclei are brought much closer together. Nuclei also seem to come closer together in a Bose-Einstein condensate. Apparently though the notion that this means fusion is considered a vulgar error. [1] As I understand it, the nuclei are smeared together in their probability distribution, but if the position of one is known the position of all the others is known to be somewhere else. Despite the talk of a "superatom", the distribution must be fairly broad then. Nonetheless... how dense can a BEC actually get? Does it get anywhere in the ballpark of fusion plasmas? There may be an answer here that I failed to understand - they give densities at a transition point, but I don't understand that to be the BEC itself?

2. It is possible to make a coherent electron source [2]. Does that mean that it is possible to bounce coherent electrons back and forth in a specially shaped chamber (or in a cyclotron-style ring), creating standing waves of electron density into which multiple nuclei might be drawn? And if so, can these waves be made smaller than the ordinary wavelength of electrons (and size of ordinary atoms/covalent bonds) by some clever wave mechanics or by making the electrons go really fast so they pick up relativistic mass comparable to that of a muon? Would that then mean they can undergo the equivalent of muon-catalyzed fusion?

3. If the electron wavelength can't be reduced, is it conceivable to do the same thing with muons, creating a coherent standing wave pattern, and pump the muons to such tremendous speed that their lifespan is extended for relativistic reasons? Wnt (talk) 21:53, 2 April 2016 (UTC)[reply]

If we could answer that Wnt, I don't think any of us would be editing WP. Instead, we would be busy trying to submit our papers to peered review journals in the quite confidence that there is a Nobel Prize waiting for us at the end of it.--Aspro (talk) 23:04, 2 April 2016 (UTC)[reply]
The Wikipedia articles Cold fusion and Muon-catalyzed fusion are not fora for general discussion about cold fusion. AllBestFaith (talk) 14:04, 3 April 2016 (UTC)[reply]
Has someone used them that way? I don't see your point. Wnt (talk) 22:08, 3 April 2016 (UTC)[reply]
The warning appears at Talk:Cold fusion. This mediation has concluded. AllBestFaith (talk) 18:42, 4 April 2016 (UTC)[reply]
OK, so perhaps someone has used them that way, but I still don't see the relevance to Wnt's question. The articles and their talk pages are not fora for general discussion on the subject matter, but questions about the subject matter can certainly be directed to the science refdesk. That's what it's for. --Trovatore (talk) 19:05, 4 April 2016 (UTC)[reply]