The Hangar

3:15 AM

I think something kind of interesting is happening at this question here:

-5

Q: What makes Airplane Fly? Does Bernoulli Principle still Reliable?

Even the earliest airplanes did not apply Bernoulli principle. The wings were flat, and it worked. An honest engineer admitted that 'take off' is a mystery. Is there alternatives for Bernoulli principle? To me Universal Acceleration under Flat Earth model is the one and only convincing concept t...

airplane

The OP is suggesting that the apparent force of gravity is actually caused by "universal acceleration". This is the hypothesis that there isn't actually a force of gravity; instead, the ground is accelerating upwards at 1 g.

The hypothesis is false, of course.

(Except that in general relativity, gravity is stuff accelerating. But never mind that for now.)

What I find a little interesting is what Jimmy is saying about the universal acceleration hypothesis.

"Universal acceleration is a ridiculous model that violates the very existence of an atmosphere that we experience. The fact that static pressure is higher towards the ground, and the fact that there is such a thing as static air with zero dynamic pressure, are evidence enough that this model is garbage."

I don't think that's true at all, and it's not obvious to me why someone would think that that's true.

To me, it seems pretty obvious that if universal acceleration were true, then static pressure would be higher towards the ground, and a stationary object in still air would see a dynamic pressure of zero—which is, of course, exactly what actually happens.

In any case, it's certainly the case that "flat earth with gravity" and "flat earth with universal acceleration instead of gravity" are completely indistinguishable hypotheses; they make exactly the same predictions.

Jimmy

4:21 AM

Uh, that's a completely incorrect interpretation of the equivalence principle, if you look at the universal accel wiki (generally the case with flat Earther theories, just enough lexicons to make their case sound scientific).

@TannerSwett You have it backwards. If you construct a freebody diagram on a fluid particle, an air without gravity and is stationary (which is what the univ accel model is suggesting), would experience no force. After all, fluid can only experience pressure or field forces.

What does this mean? It means in order for your hypothetical fluid to stay motionless, it would need opposing pressure from other air. And the only other way to create pressure it dynamic pressure. That means the fluid must be moving. Which invalidates the observation.

If you somehow believe that both ground and air are accelerating by the same field, upward, at the same acceleration (but everything else, including you and me do not experience this field), then the hydrostatic equation would apply, but now you have an acceleration upward, which would indicate higher pressure further away from the ground, again invalidating observation.

Federico

10:22 AM

someone would like to argue against closing this question as too broad? https://aviation.stackexchange.com/q/66896/1467
(asks a list of things)

and I start feeling the same here: aviation.stackexchange.com/q/66676/1467 given the amount of answers it got

Dan Hulme

@Federico it's an interesting question with informative answers

My first instinct is to make a CW answer to make a single list, but for this question I can see the value of having different candidates be voteable separately. Some of the answers are pretty marginal examples (e.g. some which never flew, despite the question specifically asking for things that have flown).

@Federico I don't think this question is at all broad. It asks for the best way to do a single, clearly-defined goal, and is answerable in a few paragraphs. It got many answers because it's an outlandish idea that made HNQ, that's all.

Federico

@DanHulme ok, thanks :)

@DanHulme I would like a CW answer as well there :/ definitely don't like single users giving multiple answers

Dan Hulme

10:38 AM

It does smack of rep-farming, especially when they're self-answers too, which is always going to make people unhappy with the question and its poster

but I think the stated justification of letting different suggestions be voted on separately has merit. It's a tricky call.

Usually with tough cases, I try to think about the real goal of closing questions: protecting the site. We close duplicates so that information doesn't get split up and hard to find. We close unclear questions as a way to get the question improved, to avoid wasting answerers' time on guessing what the questioner needs, and to make the standards for questions more visible.

Federico

ok, I agree then that closing is not the right call here, but the impression of rep-farming still stinks to me

Dan Hulme

I don't have anything to suggest about that, other than seeing if they make a habit of it. I've only had a couple of run-ins with people who were genuinely just after the internet points and didn't care about the site, content, or community at all. They always just got bored and left really quickly, before getting enough rep for interesting privileges.

JJJ

11:11 AM

@Federico Notice that they only get a maximum of 200rep per day via this way. And, to be effective this requires the question to go to HNQ, otherwise it won't see that many up votes at all. In particular, the reason one CW answer doesn't work here is that I can't selectively upvote answers (in particular, I don't like the Concorde example as it's not really about wings, so I wouldn't upvote that one but I do upvote the other answers that fit the Q).

Federico

1) it is already in the HNQ
2) the question is about variable geometries, not variable wings

JJJ

@Federico If this really stinks to you, you can consider, as other sites have done, to make such list questions CW as a site rule. That way, there's no problem of having many separate answers, they can be voted on but they won't earn reputation.

@Federico 2) my bad, I misread it. In that case it might be too broad (though that's not my decision to make, I'm merely passing by ;p)

Federico

@JJJ my problem here is that I have a user that started a list question (already not a great thing) and then proceeded to give 2 answers to said question. It really stinks, and making them CW now won't remove the rep they already farmed

JJJ

@Federico I'd say, let it be a lesson (meaning: define clearer rules on list questions) rather than retroactively making an example out of this case. Yes, they have earned a few hundred rep but it's not through deceit, the answers are actually a nice addition to the site (from my outsider POV).

Federico

but we already have rules on multiple answers, and they say "different points go in different answers, same points go in the same answer". and I cannot see how those can be seen as different points.

but ok, clearer rules for next time

JJJ

11:20 AM

@Federico I understand your concern though, and a good example of many successful lists is the big-list tag on Mathoverflow. Those are good questions, the bar for voting on them is very low (you don't incur a -1 penalty for down voting an answer), they allow editing by others, they provide canonical information and they can earn badges (so it's not all for nothing). mathoverflow.net/questions/tagged/big-list?tab=Active

@Federico I'd say make the specific rule for list questions. It addresses the rep concern, users will still be happy because list questions are allowed and not frowned upon for rep concerns, attract users to the site (because people like lists). Everyone wins (though some may oppose lists altogether, so definitely consult on meta ;p).

Federico

I am among those that think that lists are not a good thing for the SE format

and in fact they are generally frowned upon and closed as too broad

JJJ

@Federico but why, if not for the rep concern? You can't deny they are successful and useful on the Mathoverflow (and other sites, at least the general Math as well). Therefore, I'd say at least discussing it on meta to see what the community thinks is a good start, if there is a consensus either way it's easier to act in future situations.

Federico

I am trying to write

still, Math is not Aviation that in turn is not SO

what is good for Math is not necessarily good elsewhere

JJJ

@Federico well it's not just mathematicians that like lists bbc.com/future/story/20150410-9-reasons-we-love-lists. But I agree it's something for each site to consider and make clear in a meta post. That way, if you don't allow them and they do come up you can close them early.

Federico

11:35 AM

the BBC is still not this SE

Feeds

11:46 AM

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Q: What should we do with list questions?

Background: I was reviewing this question when I noticed that: it is a list question (i.e. open-ended, i.e. generally regarded as too broad) the OP posted two answers. I have asked in the comments to the second answer to please merge them in accordance to our policy. People have argued that...

discussion questions

0

Q: Should these two answers be merged?

Background: I was reviewing this question when I noticed that: it is a list question (i.e. open-ended, i.e. generally regarded as too broad) the OP posted two answers. I have asked in the comments to the [second answer][2] to please merge them in accordance to [our policy][3]. People [have ...

discussion specific-answer

AEhere

2:57 PM

@TannerSwett I have a question aimed in your general direction: aviation.stackexchange.com/questions/66916/…

Tanner Swett

9:44 PM

@AEhere Well, that's a good question! I don't have an answer.

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