Wikipedia:Reference desk/Miscellaneous: Difference between revisions
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A recent news item [https://www.denverpost.com/2021/02/21/united-airlines-engine-failure-debris-colorado-denver/] reports that a [[Boeing 777]] had an engine failure. How far can such a plane fly on only one engine? I read the Wikipedia article, but did not see that info. If the engine failure had happened midway between US mainland and Hawaii, could the plane have enough distance to reach an airport? [[User:RudolfRed|RudolfRed]] ([[User talk:RudolfRed|talk]]) 01:10, 22 February 2021 (UTC) |
A recent news item [https://www.denverpost.com/2021/02/21/united-airlines-engine-failure-debris-colorado-denver/] reports that a [[Boeing 777]] had an engine failure. How far can such a plane fly on only one engine? I read the Wikipedia article, but did not see that info. If the engine failure had happened midway between US mainland and Hawaii, could the plane have enough distance to reach an airport? [[User:RudolfRed|RudolfRed]] ([[User talk:RudolfRed|talk]]) 01:10, 22 February 2021 (UTC) |
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:Flying a twin-engined airliner (such as the 777) further than 1 hour away ''at its cruising speed with one engine failed'' from a possible landing field is known as "extended twin operations", "extended operations", or [[ETOPS]] for short: the concept has also been extended to aircraft with more than two engines, and usually refers to flights at least partially over water or remote land terrain. |
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:Every civil airliner is given an ETOPS rating that gives the upper limit of the ''permitted'' flying time with one engine out that it is allowed to get from any airfield(s) it could divert to and land at. No flight plan should be made or accepted that breaches this limit. |
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:The rating for the 777 [[Boeing 777#Entry into service|was originally ETOPS-180]]: this was later increased to ETOPS-207 in at least some circumstances: bear in mind that as with most types of airliner, there are several variants with different capabilities. My ''extremely'' rough estimate is that this would translate to about 2,000 miles, but doubtless more knowlegeable responders can and will correct this. Of course, this is an indication of what a flight plan should stay within, not the actual capability of the aircraft, which presumably is somewhat greater. |
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:According to various issues of [[Flight Magazine]] I read some years ago, airline personnel amongst themselves refer to ETOPS as "Engines Turning Or Passengers Swimming." {The poster formerly known as 87.81.230.195} [[Special:Contributions/2.125.75.168|2.125.75.168]] ([[User talk:2.125.75.168|talk]]) 01:56, 22 February 2021 (UTC) |
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February 15
Shampoo use
The typical reason o f using shampoo is to remove the unwanted build-up of sebum in the hair without stripping out so much as to make hair unmanageable. Do we need shampoo or not? It's hard to say as it can't always work for everyone but what is thus no poo moment what makes it different from using shampoo does it clean scalp the same way?
Shampoo#No Poo Movement — Preceding unsigned comment added by 203.220.94.221 (talk) 08:07, 15 February 2021 (UTC)
- We don't "need" shampoo, or at least we managed perfectly well without it until 1814. The same could be said about millions of commercial products. If you find it useful, go ahead and buy it. More information at shampoo and no poo.--Shantavira|feed me 10:33, 15 February 2021 (UTC)
- Coincidentally, we seem to have had rather a lot of shampoo related questions recently. Alansplodge (talk) 18:45, 15 February 2021 (UTC)
- Yes, all of them from Australia. ←Baseball Bugs What's up, Doc? carrots→ 21:01, 15 February 2021 (UTC)
- So oodways? Clarityfiend (talk) 02:55, 16 February 2021 (UTC)
- Maybe. ←Baseball Bugs What's up, Doc? carrots→ 20:59, 16 February 2021 (UTC)
- I haven't used shampoo for over 30 years. Can't say I've ever missed the experience. PaleCloudedWhite (talk) 21:59, 16 February 2021 (UTC)
- Eek. ←Baseball Bugs What's up, Doc? carrots→ 02:16, 17 February 2021 (UTC)
- A la Patrick Stewart? Clarityfiend (talk) 05:06, 17 February 2021 (UTC)
- Not a big deal. I hardly ever use soap per se. I use sorbolene, as my skin is sensitive to the wrong pH, and it's neutral. -- Jack of Oz [pleasantries] 21:12, 17 February 2021 (UTC)
- I haven't used shampoo for over 30 years. Can't say I've ever missed the experience. PaleCloudedWhite (talk) 21:59, 16 February 2021 (UTC)
- Maybe. ←Baseball Bugs What's up, Doc? carrots→ 20:59, 16 February 2021 (UTC)
- So oodways? Clarityfiend (talk) 02:55, 16 February 2021 (UTC)
- Yes, all of them from Australia. ←Baseball Bugs What's up, Doc? carrots→ 21:01, 15 February 2021 (UTC)
- Coincidentally, we seem to have had rather a lot of shampoo related questions recently. Alansplodge (talk) 18:45, 15 February 2021 (UTC)
I thought the movement against shampoo's idea was that we should use real poo on our hair. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 22:30, 17 February 2021 (UTC)
- Nah, they poo-pooed that idea. Clarityfiend (talk) 03:43, 18 February 2021 (UTC)
- The deal is, when it comes to hygiene, there are really two types of hygiene: cosmetic hygiene and health hygiene. Health hygiene is the sort of things we do to improve our health outcomes: washing hands with soap and water frequently is a way to reduce transmissibility of infectious agents. Brushing your teeth helps you keep them in your head longer and prevents things like gingivitis and tooth decay. Cosmetic hygiene is stuff like wearing deodorant and bathing practices (in general) and things like that. A person's culture may have certain general attitudes towards things like odors, hair and skin textures, and things like that, and those cultural attitudes will shape things like shampoo usage, deodorant and perfumes, bathing frequency, etc. Saying all of that, however, and I want to make this very clear, merely because these behaviors are culturally necessary and not biologically necessary does not make them invalid. A person's social and emotional health is just as important as their physical health, and a person who feels happier because of the interactions they get based on their cosmetics practices is not a bad thing. In other words, there may not be a health reason to shampoo your hair , but if shampooing your hair makes you feel better about yourself, that's a perfectly valid reason to do it. </rant> --Jayron32 17:41, 18 February 2021 (UTC)
- I suspect there are hundreds of millions of people in the world who don't use shampoo and live a perfectly normal life within their own culture. Marketeers and hucksters got us onto this shampoo malarkey and now 'modern' civilisation can't live without it. a bit like shaving or eating with utensils. Richard Avery (talk) 00:09, 19 February 2021 (UTC)
- I think its important where a cultural practice is not harmful, that we don't put down people who participate in that practice. Shampooing and using forks to eat are certainly not necessary practices, but neither are they harmful, and there's no need to treat people who do them as being "duped" or taken in by "hucksters". Merely because someone does things differently than you doesn't mean they should be denigrated for it. --Jayron32 14:44, 19 February 2021 (UTC)
- I tried it once for several months last year. In the end I found the whole idea to be very much a load of, well, poo. It could be also said that it left me scratching my head... Elephas X. Maximus (talk) 01:16, 22 February 2021 (UTC)
- I suspect there are hundreds of millions of people in the world who don't use shampoo and live a perfectly normal life within their own culture. Marketeers and hucksters got us onto this shampoo malarkey and now 'modern' civilisation can't live without it. a bit like shaving or eating with utensils. Richard Avery (talk) 00:09, 19 February 2021 (UTC)
February 17
semi-trash water pump
[1] Can anyone explain what a "semi-trash" water pump is? Is it just slightly better than one that is completely trash, or what? When it says 91 feet total head lift, does that mean it can pump water from ground level to 91 feet high? Not gonna buy it but have been following the madness in Houston (water and power are still out all over, people in apartment complex are portaging swimming pool water upstairs to flush their toilets) so started looking at this stuff. Thanks. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 20:35, 17 February 2021 (UTC)
- added: they do have a full-trash one.[2] I think maybe this has to do with the size of debris (rocks and stuff) that can pass through the pump along with the water, but that is just a guess. Hmm. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 20:38, 17 February 2021 (UTC)
- The first product overview says the ports can pass "soft solids up to 5/8 in. diameter", and the second "solids up to 1-1/4 in. diameter". --Lambiam 21:20, 17 February 2021 (UTC)
- Yeah that's what made me guess about semi vs full trash. Thanks. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 22:31, 17 February 2021 (UTC)
- The total head is the lift measured from the water level to the discharge, and yes, their 91 feet total head lift does mean that it can pump water up to 91 feet above the water level ... at 0 flow. Likewise, its maximum flow of 158 GPM is at 0 head. This is stated explicitly in the manual in it's specification table on page 5:
- Maximum Flow at 0’: 158 GPM
- Maximum Head Lift at 0 Flow: 91 ft.
- Note that the 91 ft maximum head lift implies a maximum discharge pressure of just under 40 psi.
- Page 5 also include a Performance Curve ... which doesn't *quite* seem to match the specification, as it appears to suggest only 151 GPM at 0' but a 97' maximum head lift at 0 flow. -- ToE 00:48, 18 February 2021 (UTC)
Articles regarding smart cities impact on demographics of cities
Hello, I look for articles which describe what impact does a smart city has on a demographics of a population.
Thanks --Exx8 (talk) 22:08, 17 February 2021 (UTC)
- Not an answer, but a comment. A study seeking to establish evidence of the effect will have to address two difficult issues. One is that there is no agreed measure for the smartness of a city, like city IQ. The second is that there may be a causal effect in the other direction, where the demographics drives political and economic decisions on the city's development. Therefore one should not expect much beyond anecdotal evidence of any impact. --Lambiam 08:00, 18 February 2021 (UTC)
- The article smart city elucidates very little. I imagine it's something like an idea of good urban planning that uses plenty of internet-age technology. (It also seems like a good platform for me to run for city council on, since I couldn't be held accountable.) This question would be a good opportunity for someone who knows more to improve the article. Temerarius (talk) 08:18, 18 February 2021 (UTC)
- Unless, ABF, a good platform for city council is all it really is. Elephas X. Maximus (talk) 01:09, 22 February 2021 (UTC)
- The article smart city elucidates very little. I imagine it's something like an idea of good urban planning that uses plenty of internet-age technology. (It also seems like a good platform for me to run for city council on, since I couldn't be held accountable.) This question would be a good opportunity for someone who knows more to improve the article. Temerarius (talk) 08:18, 18 February 2021 (UTC)
- In addition to the above, it's probably too early to measure demographic data. For one, smart cities is a very recent thing. For another, you'd need to compare before and after, requiring multiple censuses, which typically don't get done very frequently. On top of that, you'd have to control for other factors besides the "smartness". Matt Deres (talk) 20:59, 18 February 2021 (UTC)
February 18
Megan Shoemaker - Biographies of living persons
I was wanting to create a page about the model Megan Shoemaker. However, I can only find one newspaper article about her when she was starting college. There are many pages on the Internet with her photos. She made the cover of at least two magazines. She is listed in the List of Vogue Deutsch cover models. I don't know how to go about adding her biography. Plus, I'm not very good at creating new articles. I mostly just do small edits to articles.. -- Ubh [talk... contribs...] 10:24, 18 February 2021 (UTC)
- One newspaper article is probably not enough to make an article; it would be deleted for having a non-notable subject. Matt Deres (talk) 14:12, 18 February 2021 (UTC)
- I'm afraid "many pages on the Internet", "made the cover", and being "listed" somewhere count for nothing as far as Wikipedia:Notability (people) is concerned. Per that policy, she would need to "have received significant coverage in multiple published secondary sources that are reliable, intellectually independent of each other, and independent of the subject".--Shantavira|feed me 09:15, 19 February 2021 (UTC)
- Just to elaborate on the above answer; the minimum requirements to have an article at Wikipedia exist solely to ensure that there is enough source material to help write about the subject in question. A cover of a magazine is not source material. What we need basically is sufficiently in-depth biographical writing about the person so that we can read it and use what is written there to write our own article about the person using that already existing biographical information. If the biography of this person is not already written down somewhere else, Wikipedia should not be the first place it is written (see WP:NOR). --Jayron32 17:26, 19 February 2021 (UTC)
February 19
WHO News announcement puts the world population into one of three groups, at high, moderate and low risk. In what proportion are the groups, as defined?
Promotion of ivermectin use - forum shopping with misdirecting intro - no need to waste more time on this
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I'm seeking a reasonably accurate percentage of word population (or total number of people (alive)) (tentative answers added after Lambiam's feedback and some work)
respectively.
From what I can tell, doctors aren't familiar with this advice. And I'm wondering how big the impact is if that's so. If the question was "residing" instead of "born, resided, or had long-term travel", the answer would be easy - look at something like the chart I've added to the question. --50.201.195.170 (talk) 20:33, 19 February 2021 (UTC)
As for specifics: Based on the pie chart, looks like about 35% of the world population is living in a high risk country. (Purple thru Red+ Russia ~= 25%, and Green - (USA+Russia) ~=10% [- Caribbean, Central America slivers, <1%]. So maybe Answer 1: 45% of the world population is at high risk? But people could be way more or less mobile than I am guessing they are. United States + Western Europe (+ slivers for Canada and Australia, - Mediterranean Europe) ~= 10%. So Answer 3: maybe ~ 8% of the world population is at low risk. So that means Answer 2: around 47% of the world population is at moderate risk. So about 3.5 billion at high risk. About 7.2 billion people at high or moderate risk.
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February 20
I got banned from Stack Overflow, what can I do?
I just found out I have got banned from Stack Overflow for asking too many stupid questions. Here is Stack Overflow's explanation of this.
What can I do about this? It tells me to "review my questions, especially those which have got negative feedback". All my questions which got negative feedback have already been deleted. Most have a feedback rating of zero. It also tells me deleting my stupid questions won't help.
Do I really have to wait half a year before I get a chance to ask a new question? Stack Overflow is a great aid in my job.
I have only got banned from the main Stack Overflow site. I haven't got banned from any other site on the Stack Exchange. JIP | Talk 16:03, 20 February 2021 (UTC)
- It reads like the answer is to try again in 6 months. ←Baseball Bugs What's up, Doc? carrots→ 17:30, 20 February 2021 (UTC)
- One thing you obviously can do is make a new account (preferably with a different browser and IP). Now, whether you may and should, considering your account still works on other sites... Elephas X. Maximus (talk) 01:06, 22 February 2021 (UTC)
February 22
Boeing 777 range with 1 engine
A recent news item [11] reports that a Boeing 777 had an engine failure. How far can such a plane fly on only one engine? I read the Wikipedia article, but did not see that info. If the engine failure had happened midway between US mainland and Hawaii, could the plane have enough distance to reach an airport? RudolfRed (talk) 01:10, 22 February 2021 (UTC)
- Flying a twin-engined airliner (such as the 777) further than 1 hour away at its cruising speed with one engine failed from a possible landing field is known as "extended twin operations", "extended operations", or ETOPS for short: the concept has also been extended to aircraft with more than two engines, and usually refers to flights at least partially over water or remote land terrain.
- Every civil airliner is given an ETOPS rating that gives the upper limit of the permitted flying time with one engine out that it is allowed to get from any airfield(s) it could divert to and land at. No flight plan should be made or accepted that breaches this limit.
- The rating for the 777 was originally ETOPS-180: this was later increased to ETOPS-207 in at least some circumstances: bear in mind that as with most types of airliner, there are several variants with different capabilities. My extremely rough estimate is that this would translate to about 2,000 miles, but doubtless more knowlegeable responders can and will correct this. Of course, this is an indication of what a flight plan should stay within, not the actual capability of the aircraft, which presumably is somewhat greater.
- According to various issues of Flight Magazine I read some years ago, airline personnel amongst themselves refer to ETOPS as "Engines Turning Or Passengers Swimming." {The poster formerly known as 87.81.230.195} 2.125.75.168 (talk) 01:56, 22 February 2021 (UTC)