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[–] 60 points 1 month ago
[–] 77 points 1 month ago (21 children)

Probably not because it's extremely useless for 99% of people lol

Does the average person know that a stalagmite is mostly calcium carbonate?

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  • [–] 27 points 1 month ago (3 children)

    Well no, why would they remember that? They've got to remember the chemical formula for one or two quartzes

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  • [–] 10 points 1 month ago (6 children)

    I knew both! AuDHD for the win.

    Umm...what were we talking about again?

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  • [–] 6 points 1 month ago (5 children)

    Maps, I think? Or ships. Possibly trains...

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  • [–] 3 points 1 month ago (4 children)

    I swear it was neutron stars.

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  • [–] 1 point 1 month ago (3 children)

    What if life were to evolve on a neutron star?

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  • [–] 2 points 1 month ago (4 children)

    Maybe people do know that?

    Drinking / tap water here comes from a limestone aquifer. Tap ware and shower screens and toilets develop a calcium carbonate build up that needs to be chemically removed.

    I think anyone who's been in a cave and heard how stalagmites form would remember that it's calcium carbonate.

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  • [–] 3 points 1 month ago (2 children)

    I learned about it in school and have seen them in a caves but still had to look it up for the bit.

    How about this...does the average person know that the transport latency of Dante audio is around 150 microseconds?

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  • [–] 28 points 1 month ago (3 children)

    No. Most people think you can throw a lit cigarette or lighter on it and it will go up instantly too because of movies. I think Die Hard 2 was the worst lol, he like threw a zippo in the puddle of her fuel and then it followed the plane in mid air to blow it up.

    I don't think people know how octane level works either. I think they assume higher octane is easier to combust when it's the exact opposite.

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  • [–] 12 points 1 month ago (1 child)

    I don't know how easily it blows up, I'm too cool to turn around and watch the explosion

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  • [–] 12 points 1 month ago (16 children)

    The entire point of jet fuel is that it DOESN'T "blow up easily", though.

    unlike gasoline, It actually takes quite a bit of effort to ignite avgas in it's liquid form because it's designed to be aerosolized before being ignited.

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  • [–] 3 points 1 month ago (8 children)

    And... Is this post about 9/11?

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  • [–] 4 points 1 month ago (4 children)

    No one mentioned 9-11. I'm not sure what you're getting at.

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  • [–] 5 points 1 month ago (3 children)

    I assume it's a reference to one of the 9/11 conspiracy theories.

    The claim was that jet fuel doesn't burn at a high enough temperature to melt steel. Therefore a bunch of burning jet fuel alone wouldn't have been enough to collapse the towers. Therefore someone must have put something else there.

    Even XKCD got in on the joke. https://xkcd.com/966/

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  • [–] 2 points 1 month ago (2 children)

    You are nearly spot on: it isn't just the heat it will produce, but the lack of ignition due to the oxygen required for ignition.

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  • [+] [S] 1 point 1 month ago (3 children)
  • [–] 0 points 1 month ago* (2 children)
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  • [–] 2 points 1 month ago (3 children)

    I thought Avgas was 100ll, not jet fuel?

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  • [–] 1 point 1 month ago (1 child)

    I can't remember the which is which. I just remember that Avgas and 100ll are the two types of aviation fuel. My brain doesn't have the ability to remember which is which. Which is probably why it's a good thing I'm not a pilot...

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  • [–] -1 points 1 month ago

    Once years ago, I used a few mL of gasoline as a solvent to clean grease from a part. To dispose of it, I put it in a can and tossed a lit match in.

    The liquid gasoline extinguished the flame. Even gasoline is hard to ignite.

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  • [–] [S] 11 points 1 month ago* (last edited 1 month ago) (1 child)

    Its high flash point also makes it hard to ignite making it safer than gasoline.

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  • [–] 16 points 1 month ago* (last edited 1 month ago) (6 children)

    Does the average person know that it costs $2500 in fuel to get a boeing 747 off the ground?

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  • [–] 1 point 1 month ago (4 children)

    So like four people in Business class cover it...

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  • [–] 1 point 1 month ago* (3 children)

    Yeah, I thought it was supposed to be the main expense for airlines.

    Edit: Oh, that's literally just takeoff.

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  • [–] 2 points 1 month ago (2 children)

    Yeah I can imagine the rest of business class pays for the flight and economy is just a cherry on top. I mean they keep making the seats smaller to can in more fish. Some older planes you can tell they were fitted with the modern small seats. Paid for the window view? Enjoy your wall view. Then overbooking. And the kicker, your luggage requirements keep shrinking, so they can ship things.

    https://liveandletsfly.com/united-airlines-f35-parts-israel-passenger-flights/

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  • [–] 1 point 1 month ago* (1 child)

    Airlines are going bankrupt all over the place, though, so it's not like they're making massive margins. Basically, people just prefer a shitty seat on a cheap flight.

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  • [–] 2 points 1 month ago

    I get that; flying is made to be such a pain now. When I flew ANA, Japan Airlines, or the Redeye; it was nice. Any US flights were torture. Being 6ft tall with back problems, it makes sleeping in cargo feel like a 5 star hotel.

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  • [–] 8 points 1 month ago

    I did not know, I must confess. I know now. Knowledge is power.

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  • [–] 8 points 1 month ago

    Are we still doing 9/11

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  • [–] 6 points 1 month ago

    Bro the average person doesn't even know you can compile software for different architectures.

    They aren't gonna know about jet fuel which is almost as complex

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  • [–] 5 points 1 month ago (1 child)

    The average person probably has no idea what cracking is to begin with.

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  • [–] 17 points 1 month ago (10 children)

    I bet the average person knows it can't melt steel beams.

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  • [–] 37 points 1 month ago (9 children)

    And the average person should also know that steel doesn't need to melt to lose a lot of it's load bearing capacity. At 500-600 Celsius, only 50% of steel strength remains.

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  • [–] 2 points 1 month ago* (last edited 1 month ago)

    Which, going right back around to jet engines, is why superalloys are a thing.

    They aren't stronger or even more refractory than normal steel, just more expensive, but they don't soften at all until they're about to melt.

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  • [–] 0 points 1 month ago* (5 children)

    Plus there would be wind fanning those flames hard which could raise the temperature some.

    But the other thing to consider is that the towers could have been built with substandard materials in the first place.

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  • [–] 2 points 1 month ago* (2 children)

    IIRC, the materials were fine, but the spray-on fireproofing left large patches uncovered. While not a direct cause, it certainly didn't help.

    WTYP has a pretty good episode on the entire thing

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  • [–] 3 points 1 month ago (1 child)

    This just in: scientists have determined that a more direct cause for the towers falling than defective spray-on fireproofing may exist. Rumors have begun to circulate that the WTCs collapse may be attributed to the two aircraft which collided with them. Details at 6.

    (I kid, I kid)

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  • [–] 1 point 1 month ago

    Well, it would've collapsed either way, as you can see on the pictures during the fire that the metal is starting to buckle uniformly around the entire floor with the fire. But patches without insulation probably meant that it collapsed sooner than it could've.

    Didn't help anyone trapped, so the net result is the same in that I fail to see how 30 minutes extra before it crumbled would've made any difference

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  • [–] 4 points 1 month ago

    It's taxed differently as well

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  • [–] 4 points 1 month ago

    I knew, but only because I read a lot of cold war stories, and for war becomes hot stories. Running a jet on cooking kerosene was a plot point in one

    I have since read about just engines and jet fuel

    I don't work in that industry at all. I'm an IT systems analyst

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  • [–] 4 points 1 month ago*

    Probably not. Same as movie directors don't seem to know what happens when you throw a lit cigarette in gasoline: it puts it out. Diesel doesn't ignite even with a match.

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  • [–] 4 points 1 month ago

    Likely not. I thought it was highly volatile until I learned it was basically kerosene.

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  • [–] 4 points 1 month ago

    I don't think they do. I'm a person that likes aviation and I never think about jet fuel.

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  • [–] 4 points 1 month ago

    No. I wager the average person thinks its some kind of super dangerous super powered liquid explosion magic, because the average person is kind of an idiot.

    I, however, did know its fancy kerosene

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  • [–] 3 points 1 month ago* (last edited 1 month ago)

    No. I'd guess a lot of people, who don't work with it, think diesel blows up, even.

    What the basic kinds of petroleum are, and which vehicles they go in, is one of those things any reasonably educated person should know, but the majority of the population actually won't.

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  • [–] 3 points 1 month ago (2 children)

    I’ve known it since the 7th grade and I ain’t particularly bright.

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  • [–] 3 points 1 month ago

    I was in school training to be an aircraft mechanic when I learned that. I remember thinking, "that's crazy"

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  • [–] 6 points 1 month ago (5 children)

    I personally didnt and now it makes me question whether it can melt steel beams

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    [–] 4 points 1 month ago

    This one did, at least in general terms

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  • [–] 2 points 1 month ago

    Also basically the same as diesel fuel. All three are interchangeable in an emergency situation. They each have different additives and are taxed differently. Also home heating oil too.

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  • [–] 2 points 1 month ago

    Yes. Speaking for myself.

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  • [–] 1 point 1 month ago

    Red to orange hot and the fucker will bend.

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  • [–] 1 point 1 month ago
    [–] 0 points 1 month ago

    I'd think so, yes.

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