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What other unsubstantiated claims did she make?
by kace91 6y ago
What other unsubstantiated claims did she make?
- zamfi 6y agoI'm not the original poster, but I was shocked by how many of the otherwise super smart friends I had in college were taught common falsehoods in high school. For example: the idea that your veins look blue through your skin because the deoxygenated blood in them is blue, and that it only turns red outside your body because it's exposed to oxygen.
- jcomis 6y agoOr the whole taste bud taste map of the tongue.
- nikisweeting 6y agoI think a lot of them have only been solidly disproven in the last ~15 years, and it takes some time for that science update to propagate through the world.
- elihu 6y ago...especially in a time before Internet access was common.
- monk_e_boy 6y agoOr how wings work.
- lozaning 6y agoFor anyone thats interested in what the parent is talking about: http://www3.eng.cam.ac.uk/outreach/Project-resources/Wind-turbine/howwingswork.pdf http://www3.eng.cam.ac.uk/outreach/Project-resources/Wind-tu... I've had people get like legit upset at me when i correct this.
- tidenly 6y agoMy god, thank you. I remember as a kid this explanation "the top has to move fast to meet the bottom stream at the trailing edge" always confused the hell out of me. Why do the top and bottom have to meet? How would they know? Even as a 10 year old it confused me no-one could answer this.
- monk_e_boy 6y agoEspecially for hydrofoils. Makes no sense
- GuB-42 6y agoThat's the now famous Bernouilli vs Newton debate. Personally, I am in camp Newton. Not that Bernouilli doesn't work, they both give the same results in the end, and they are both a simplification of the "truth" which is the Navier-Stokes equations. The reason I like the Newton explanation better is that if you start with the Bernouilli principle, it is much easier to come up with the wrong idea. The Newton is straightforward: push air down, plane goes up. A bit shallower but at least, the basic idea is hard to get wrong.
- rcxdude 6y agoIt's reasonable to phrase the working of a wing either in terms of momentum or in terms of a different in pressure between the top and bottom. What's incorrect is when trying to explain the action through bernouilli it's often asserted that the air above the wing must take the same time to transit the wing as the air on the bottom. Not only is this completely unjustified to assume when trying to solve the problem, it's also false in practice: in general air above and below will not pass the wing in the same time, even though the air over the top is travelling faster.
- parsecs 6y agoOr how reentry heating is apparently caused mostly by friction. (Compression of air is the main cause in actuality)
- pfdietz 6y agoNo, actually friction is closer to the truth. It's air running into air at a shock, a process that generates entropy, just as friction does. Compression is a process that is adiabatic, generating no entropy. And in an ideal gas the density increase across a shock reaches a finite limit even as the mach number goes to infinity.
- bernulli 6y agoI am having trouble seeing how compression in a shock would be isentropic? Care to elaborate? And why passing through a shock (compression) is akin to friction, but not to compression?
- pfdietz 6y agoBecause compression, as normally considered, does not generate entropy. It causes gas to become hotter because the temperature has to be higher for entropy to remain constant, as the volume is reduced. This is a reversible process. But shocks are inherently irreversible. But as my last sentence said, as the mach number goes to infinity the density increase across the shock is finite. Therefore, compression cannot be the (primary) source of the heating; dissipation is.
- bernulli 6y agoI have never seen compression to be considered inherently reversible, certainly not in the aerospace or hypersonics/reentry communities. I assume you come from a different background? Care to explain your second argument? Even when the density reaches a limit, the change in pressure over the shock does not, so you can pump in energy arbitrarily (of course your gas would dissociate at some point). The total pressure loss can be complete if your initial Mach number is high enough.
- jiggawatts 6y agoOne of my favourites is the myth that Iodine doesn't melt: https://www.youtube.com/watch?v=dPIaEWd8zf4 https://www.youtube.com/watch?v=dPIaEWd8zf4
- nikisweeting 6y agoTo be fair it was usually small, inconsequential things, not major parts of the curriculum. The only major one I remember is that water is conductive by itself. And that "C++ is the best programming language" (hah).
- p1necone 6y agoI'm sure you could make the argument using some definition of best. Perhaps best in it's impact via software created in it rather than the language itself. Although then I think C would win over C++ because of Linux. I'm imagining a slightly tongue in cheek 'best' alongside an implication of subjectivity. But given this was a highschool teacher I wouldn't be surprised if it was instead a multi choice test question with a single "correct" answer? Which of course would be ridiculous.
- nikisweeting 6y ago"make the argument using some definition of best" I won't take the bait to dive into that discussion! ;) Luckily she never tested us on it, I think she was understandably biased from working in C++ in an earlier job.
- wombatmobile 6y ago> To be fair it was usually small, inconsequential things I’ve always wondered about this bit: “One nation, under God, with liberty and justice for all”
- K2h 6y agoOnly 1 set of ‘primary’ colors
- jeffbee 6y agoThat traits of human physiology are heritable binaries. https://udel.edu/~mcdonald/mythintro.html https://udel.edu/~mcdonald/mythintro.html
- pilsetnieks 6y agoI think there's only so much time children can spend on learning all their subjects, so they learn Mendelian genetics, Darwin's evolution, Rutherford's atomic model because they're easy to understand, and close enough approximations for everyday life for non-specialists.
- jeffbee 6y agoSure, but some of those things they used to teach us about aren't heritable traits at all. The article recommends studying examples that fit Mendel's model.
- pjmorris 6y agoNot the OP, but a fourth grade substitute teacher made the claim that we always saw the same side of the moon because it didn't rotate. I don't know what got to me the most: that she didn't understand, that my attempt to explain it didn't go over, or that the other kids in the class didn't get it either. In any case, I've been working on improving my explanations ever since.
- hervature 6y agoWhat's your explanation now? I think people just get tripped up thinking about rotation of an object in circular motion and just ascribe one motion for the other. For example, if you imagine a newly reunited couple and they hug each other while simultaneously spinning, this is exactly what the moon and Earth are doing. I think most people would also say that the outside person isn't rotating. However, they would also say that the inner person is obviously spinning. Describing in words is often not the best way to impart explanations of physics, but the easiest way to show this concept for me is to imagine both people separately and consider a half turn. The inner person, rotates 180 degrees, simple rotation. What does the outside person have to do to get to the right position? They have to walk around the inner person to the other side and then rotate 180 degrees to see their partner again.
- solipsism 6y agoAnd your beef is that it does rotate, at a rate of one rotation per revolution? Sounds kind of pedantic to me, and confusing (certainly to kids).
- mercutio2 6y agoThe fact that we live our lives in a non-intertial reference frame is pretty mind blowing to everyone, I suppose. Doesn’t seem like a small point to me.
- pjmorris 6y agoI'll grant that I was a pedantic fourth grader. And I'll grant that the other kids didn't care. Still, seems to me that the teacher could at least skip the topic if it's confusing.
- nemo44x 6y agoAlmost everything we think (including me) is probably trash. We just need to accept we are mostly idiotic. Unless we put the time in to understand something that _maybe_ is somewhat understood by people that have put their lives into it. Truth is (heh) we are all mainly full of shit. We think we know more than we do. We confuse truth for BS constantly. We spend countless breaths debating unfalsifiable opinions as if they’re true - like we really know something. We are all mainly dumb at most things.
- ordu 6y ago> Almost everything we think (including me) is probably trash. We just need to accept we are mostly idiotic. I do not like this attitude. Everything is false, because the truth exists only in ideal condition of math. But it doesn't mean that we are all idiotic and know nothing worthy knowing. The trick is to understand the relation between knowledge and the reality, to feel this relation in your guts. It helps to know a lot of falsehoods, and to be smart, even wise and knowledgeable. > We are all mainly dumb at most things. I could agree with this, because to really know something one needs to spent all his life researching the topic. And even the life full of the dedicated research might be not enough. But as I see, to be dumb is not so about having no knowledge, as about having no idea of limits of one's knowledge.
- nemo44x 6y agoNo - truth doesn’t only exist in an ideal condition of math. I mean, yes maybe literally in some ways, maybe. But not really. Math doesn’t prove the sky is blue on a sunny day. My main point is that of falsifiability. You don’t need math to make a falsifiable argument. However, much of our discourse can’t even meet this basic qualification.
- ordu 6y ago> Math doesn’t prove the sky is blue on a sunny day. Yeah, it doesn't. So it is not a truth, but a belief. It is pretty strong belief, so strong that it almost indistinguishable from the truth. But nevertheless it is just a belief. > My main point is that of falsifiability. You don’t need math to make a falsifiable argument. However, much of our discourse can’t even meet this basic qualification. Even falsifiability is a too rigid property for some discourses. My main point is that attempts to find a silver bullet to shoot "bad beliefs" are no-go. Knowledge couldn't be bad or good, true or false. It is the way knowledge applied could be good or bad. For example, even "the sky is blue on a sunny day" could be misapplied. Take the sky of a Moon or a Mars for example, which are not blue in a sunny day. Or let us imagine atmosphere of Earth with a lot of dust after collision of Earth and an asteroid: on such Earth sky could be orange, or gray or of some other color. I mean that even "true" statements have limits of their truthiness. As an opposite example, a "false" statement could be applied in a "good" way. Earth is flat? Oh, yes, it is convenient to think so when dealing with a relatively small area of the Earth surface. Or when communicating with people, who believe that Earth is flat. You need only to remember the limits of this belief, to not misapply it accidentally. In math the situation a little different. Math statements also could go wrong when assumptions change (the sum of angles of a triangle could be not equal to PI, if triangle drawn not on a plane but on some other surface), but mathematicians make sure to strictly state all the assumptions as axioms and definitions. It is possible in ideal conditions, but not possible in real ones.
- elliekelly 6y ago"You won't always have a calculator in your pocket." - Every math teacher before 2005
- askvictor 6y agoCentrifugal force is a common one: https://xkcd.com/123/ https://xkcd.com/123/