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  • The last comments in the image are exactly right.

    It bothers me when I screw up and someone says "I fixed that for you" without explaining how I screwed things up, or how they fixed it.

    If I'm wrong, I get it. I'm not always right, nobody can be right 100% of the time, IMO, that's impossible. But when I'm wrong, let me learn so I can avoid being wrong in the same way twice.

    IMO, schools have failed us, they teach us what we should know but don't encourage us to always be curious and always be learning. It's okay to make mistakes, and it's okay to be wrong. What's not okay is never learning from your mistakes, and being so stubborn that when you are wrong, you double down on being wrong instead of seeking more information so you can be correct next time.

    Being wrong is always condemned. You get low grades, you fail and get held back in some cases.... It's been rare that any teacher I've ever had would review anything from a test after its over. A very small number went back and said "a lot of people had trouble with x question from the test, here's the answer and this is why it's the correct answer". IMO, that should be way more common.... Review the test after its over and let the class know that low marks are not the end, they're a wonderful beginning to learning. If you know what you don't know and you have even the smallest amount of ability and willingness to improve, with the addition of opportunities to learn that, then you will always succeed.

    Be successful. Get a bunch of shit wrong.

    • I'm glad you addressed the aversion to being wrong because I think that's part of the core of what's causing so many problems in America today (and maybe other places, but I can only speak to my own familiarity).

      I feel like as a society we have created an environment where we demonstrate and reinforce to children from like kindergarten onward that the worst thing you can possibly do is be wrong. Someone who is always right is seen as smart, capable...in short, a winner.

      Conversely, if you're ever wrong, that completely and permanently undoes your entire argument/position and not only that, but you're branded as unreliable/untrustworthy, uninformed, stupid, dishonest, or naive.

      We expect perfection in correctness, and while being right is the expectation, being wrong is a permanent black mark that is treated as a more serious negative than being right is considered as a positive. Nobody just assumes that if you're right about one thing that you'll be right about all things, but if you get something wrong, there's a very real shift toward double-checking or verifying anything else that comes after.

      We even tease friends, family, and children for mispronouncing words or singing incorrect lyrics. Basically, being incorrect is so stigmatized that we reinforce to everyone, children and adults alike, that it's better to not even try...not even make an attempt or join into a conversation...than to risk being wrong. When someone is wrong we use words like "admit" like it's a crime, or admit defeat...and that just creates an environment where nobody is ever encouraged to speak up about anything for fear of (gasp!) being wrong.

      And now we're coming full circle on this at the highest levels, with our leaders being blatantly and objectively wrong...and absolutely dead set on avoiding having to admit that at all costs, setting a precedent that has oozed into even casual discourse among regular people. It seems like it used to be that being wrong was bad enough, but to dig in and refuse to admit it was even worse...lately it seems that admitting you were wrong is now even worse than doubling down on it...so now we have a situation where we can't even agree on basic facts because one or more sides will be wrong but would rather insist on their position than just acknowledge​ they were incorrect.

      • You're hitting on every point I could make.

        My advice to anyone reading, and wanting to be okay in being wrong, the first step is admitting you don't know something. Even if it's something you should know. For example if you're considered to be an "expert" or at least very knowledgeable about something and someone asks you about that specific thing, but it's not something you know, avoid making things up, or trying to derive an answer from what you do know. Explain that you're not sure what the right answer is, but you'll figure it out, then do some research to figure it out. Don't go off the cuff and start informing people of what you presume it is based on what you know, without knowing for sure.

        The next step is when someone contradicts what you believe to be true, hear them out, then do whatever lookups and research you need to figure out if they're right, or you're right. Don't immediately tell them they're wrong, just listen, then find the truth and go from there.

        The other thing I do, is I stay away from absolute statements as much as I can. Instead of saying that this thing I know is absolute and true, I preface it with qualifying statements like "I believe...." Eg, "I believe you need to use that switch over there to do the thing" rather than "use that switch to do the thing". If you're wrong then it was qualified as an uncertainty which can make a correction sting that much less.

        Finally, always pursue the truth above all else. The point shouldn't be whether you are right or wrong, the point is getting and giving true information to/from others. When getting seemingly true information from someone, trust but verify anything you're told before passing that information along, whenever possible.

        Always be learning, always be seeking the truth, always verify the statements of others. After a while, you'll find that you're right far more often than when you're wrong... Having that kind of track record will help in your ability to handle the times that you're found to be wrong and you'll have a much easier time with it.

        The whole thing is a process, so don't beat yourself up over it. You will falter and catch yourself doing things wrong and making assumptions and providing information you later determine to be wrong. It will happen. Learn the correct information and move forward. When you lose, don't lose the lesson.

        There's a ton more that I could say on the matter, but I think that's the core points.

        For me, I got a huge wake-up call while working at a large software provider doing end user support. I went to the escalation team and asked them about a problem, and they asked me about some of the details, when I provided them, they questioned "did you verify this? Or did you just take the customers word for it?".... I didn't verify the information. They sent me back to verify the situation before they would engage on the matter, and IIRC, it ended up being one of the assumptions that the end user, or I made, which wasn't configured correctly, that caused the problem. I managed to avoid needing escalation. From then on, "trust but verify" was a constant mantra. I've been growing and learning ever since.

    • https://o-date.github.io/draft/book/failing-productively.html

  • I just looked up the elephant vs mouse segment. The way the elephants reacted, I kinda feel like they're being cautious because they recognize a harmless lil animal and don't want to step on it. Like they behave pretty much exactly how I do when I see a little spider or frog or cricket or something. like "whoa there buddy, you dont wanna be under my feet"

  • I would say escaping from quick sand and escaping from an alligator chasing me were two major concerns in my childhood. LoL, global climate change was maybe not even on the list, for which I will curse the petroleum industry.

  • My favorite is the fan mounted to the boat blowing the sail causing the boat to move. I mean there are a shitload more experiments in fun episodes that are far better and more entertaining, but this one is my favorite because it flies in the face of logic. It shouldn’t work. My brain rejects the possibility. But physics and fluid flow work otherwise and I found it pointlessly infuriating only because I’d been unassailable in my confidence that it couldn’t possibly work. Yet there it is with a perfectly logical explanation. I still find it irritating even if I accept the reality of it. (Episode 165 if anyone’s wondering)

    That said, I still follow Adam on various platforms. That enthusiasm and joy of discovery is all still there, along with some maturity and some life observations. Literally the only celebrity figure I follow.

  • My favorite is planes on a treadmill.

    Mostly because fans still argue about it and it’s hit the point they had to ban PoaT comments.

    Which is insane as it’s not that difficult to understand. When a plane is on the ground, its gear/wheels will roll at ground speed, but the wings provide lift at airspeed.

    If the ground is being moved under the plane (as on a treadmill,) the wheels will just roll faster.

    Sure they’re not zero friction and some of that needs to be overcome; but this is something encountered on a daily basis all across the world- or rather, the opposite.

    If the wind is coming from ahead, its airspeed is increased and the plane needs a lower ground speed to get into the air where if the wind is coming from behind, then they need more.

    (This is why carriers set course into the wind when launching jets,)

    At no point is ground speed and airspeed necessarily the same (i suppose you could have a calm day, but most days, the wind is blowing at least some.)

    • Which is insane as it’s not that difficult to understand

      I found it hard to understand because neither they nor any of the other sources I've seen explaining this even attempted to answer what I thought was an incredibly obvious question: at what point does this become true? A stationary aeroplane on a treadmill will obviously move with the treadmill. I assume an aeroplane moving at like 1 km/h still gets pulled backward by the treadmill. At what point does the transition occur, and what does that transition process look like? Why can't a treadmill prevent the plane from taking off by pulling it backwards by never letting it start getting forward motion? Where does the lift come from?

      I can understand how a treadmill doesn't stop a plane that's already moving, but how does it get lift if it is prevented from accelerating from 0 to 1 km/h of ground speed (relative to the real ground—relative to the ground it experiences, it is moving forward at the same speed as the treadmill is moving backward), since until it starts getting lift, airspeed and ground speed are surely effectively equal (wind being too small of a factor)?

      • A stationary aeroplane on a treadmill will obviously move with the treadmill. I assume an aeroplane moving at like 1 km/h still gets pulled backward by the treadmill.

        so, every wheel or ball or any other kind of rolling-thing has rolling resistance, which is how we sum up the total drag on the system. A steel ball bearing on a steel plate will have a significantly lower rolling resistance than, say, a steel cube on that same plate. Tires have some- but not a lot- of rolling resistance.

        You can see that in a car, just put it into neutral and watch as you slow down, even on flat ground. Plane wheels also have rolling resistance. it's just the way our world works. But it's generally ignored because it's hard to model perfectly and in any case pretty negligible relative to the amount of acceleration being put out by modern aircraft engines.

        A treadmill will only push an aircraft or whatever else along, with an acceleration that is equal to, or lower, than the rolling resistance. If you try to accelerate the plane faster, it'll 'slip', and the plane will remain largely stationary- like the dishes in the tablecloth trick (if you want to try that at home... make sure the tablecloth doesn't have a hem, heh.)

        But, keep in mind you're thinking about the plane relative to either the ground, or the treadmill's belt.

        the plane's wings and it's engines are 'thinking' about the plane relative to the air it's moving through. It's the airspeed that generates the lift, and the engine isn't coupled to the wheels, they're just rolling along doing their thing. (aircraft engines work by taking a volume of air and accelerating it. newton's equal-and-opposite does the rest.)

      • but how does it get lift if it is prevented from accelerating from 0 to 1 km/h of ground speed

        That’s the thing - it is not prevented from accelerating. The wheels are functionally frictionless. That’s why planes have brakes. The plane pushes on the air to move, & the treadmill could accelerate backwards until the plane’s tires explode.

      • The key insight is that the force a plane uses to move is independent of the ground, because planes push on the air, not the ground.

        Imagine you put a ball on a treadmill and turn it on, what happens? The ball starts to spin and move with the treadmill. Now take your hand and push the ball backwards against the motion of the treadmill, and the ball easily moves in that direction. The force your hand put on the ball is exactly what planes do, since they push on something other than the ground (the treadmill) they have no problem moving, no matter how fast the treadmill is moving.

      • The point it occurs at is when the plane uses the air to propel itself.

      • at what point does this become true?

        It's always true.

        A stationary aeroplane on a treadmill will obviously move with the treadmill

        What do you mean? The plane has its parking brakes on and moves with the treadmill surface? If you don't have parking brakes engaged and start up a treadmill under a plane, the plane's wheels will spin and the plane will stay pretty much in one place. Because the wheels are free to spin, initially that's all that will happen. The inertia of the plane will keep it in place while the wheels spin. Over time, the plane will start to drift in the direction the treadmill is moving, but it will never move as fast as the treadmill because there's also friction from the air, and that's going to be a much bigger factor.

        I assume an aeroplane moving at like 1 km/h still gets pulled backward by the treadmill.

        Moving at 1 km/h relative to what? The surface of the treadmill or the "world frame"? A plane on a moving treadmill will be pulled by the treadmill -- there will be friction in the wheels, but it will also feel a force from the air. As soon as the pilot fires up the engine, the force from the engine will be much higher than any tiny amount of friction in the wheels from the treadmill.

        but how does it get lift if it is prevented from accelerating from 0 to 1 km/h of ground speed

        It isn't prevented from accelerating from 0 to 1 km/h of ground speed. The wheels are spinning furiously, but they're relatively frictionless. If the pilot didn't start up the propeller, the plane would start to move in the direction the treadmill is pulling, but would never quite reach the speed of the treadmill due to air resistance. But, as soon as the pilot fires up the propeller, it works basically as normal. A little bit of the air will be moving backwards due to the treadmill, but most of the air will still be relatively stationary, so it's easy to move the plane through the air quicker and quicker until it reaches take-off speed.

    • Plane on a treadmill is really interesting because if you understand how planes work its so obvious what will happen you don't need to test it. Planes move on the ground by running their engines, which push against the air, the wheels provide zero motive force. It's also why planes need tugs to move away from the gate, you can't run the engines in reverse. Planes are not cars, but people tend to assume the thing they don't understand works like the thing they do understand, and refuse to believe their hasty assumption is wrong even when told directly their hasty assumption is wrong.

    • I think the confusion is that the conveyor belt is running at a fixed speed, which is the aircraft's takeoff speed. That just dictates how fast the wheels spin, but since the plane generates thrust with its propeller, the wheels just end up having to spin at double takeoff speed. Since they're relatively frictionless, that's easy.

      The more confusing myth is the one where the speed of the conveyor belt is variable, and it always moves at the same speed as the wheels. So, at the beginning the conveyor belt isn't moving, but as soon as the plane starts to move, and its wheels start to spin, the conveyor belt movies in the opposite direction. In that case, the plane can't take off. That's basically like attaching an anchor to the plane's frame, so no matter how fast the propeller spins, the airplane can't move.

      • Except it’s not like attaching an anchor. The plane isn’t physically attached.

        The wheels will just roll double whatever the current ground speed is. If the plane has enough thrust to take off with the treadmill moving an inverse of its take off speed, then it has enough force to start rolling, too.

        At most, the force applied by the treadmill would be sufficient over enough time to lengthen the take off roll, but given enough space to do so, the plane will take off.

        To keep the plane from rolling forward; the treadmill would have to be able to apply an equal force as the engines, it can’t do that through the wheels- the wheels can only apply a force equal to their rolling resistance and friction in its mechanics.

    • Plane on a treadmill always seems so obvious to me. Planes don't have power connected to their wheels. Put a plane on a dynamometer and crank the engine up as fast as it will go, and the wheels will still not spin. At the same time, water planes use pontoons and are still able to take off just fine.

      The question I have is, can a plane take off with a tailwind that matches the speed that the propeller is pushing out.

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