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Cake day: June 14th, 2023

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  • Bernoulli’s explanation and Newton’s explanation are the same explanation made from different frames of reference. They’re equal, I don’t understand why people insist that one or the other is incomplete or that they somehow both have different contributions to an airplane’s flight. They’re the same. The airplane flies because the air pushes it up turning some of the energy from its substantial forward movement through said air into enough upward acceleration to counteract gravity. That happens both due to pressure differential AND the sum of the deflection of air in exactly the same measure, they are directly linked and have to be equal. Bernoulli’s explanation is one particularly nuanced and clever way of looking at and understanding the exact mechanics of how that happens and if you plug the resulting values into Newton’s math it matches perfectly. The zero “angle of attack” for a cambered airfoil shape is actually measured this way not by measuring the angles of the physical surfaces or anything like that. The Newtonian explanation is just another way of looking at it. Either way it requires intense computations to come to exact numbers, but the numbers are the same either way. The pressure differential of the air IS the mechanical force of the air, happening as an equal and opposite direction to the deflection of the volume of air the plane is flying through, either of which is what we call lift. They’re all the same thing, happening at the same time and yes you can look at them from different perspectives but that doesn’t mean one perspective is wrong and the other is right. They’re all accurately describing the same thing. It is useful to know both, but not necessary and it does not make either of them incorrect.

    This discussion always reminds me of the “airplane on a treadmill” argument where both sides read the premise differently and scream at each other that only their way of interpreting the question is right.




  • Most cheap non-dimmable LEDs have drivers that use resistors to determine the current to drive through the LEDs. As a rule, these are always set too high to overdrive the LEDs (sometimes as much as twice their rated current) for marginal brightness gains and to burn out the bulb prematurely. I’m obviously unable to actually see directly into the operation of the great minds that design LED lightbulbs but logic leaves me with only those two plausible conclusions, I’ll let you decide which motivation you think is a bigger factor for most manufacturers.

    Conveniently, most manufacturers carefully fine-tune this value to prematurely destroy the LEDs at just the right time, which requires careful balancing of resistors, and even MORE conveniently (for us) the cheapest way for them to do this is typically to use two resistors. And MOST conveniently (for us), if you were to carelessly break one of the pair of resistors they use, and leave the other one intact, the current would immediately drop to a very reasonable and appropriate level, generating much less heat, drawing much less power, making LED death extremely unlikely, and only modestly reducing brightness in many cases, because LEDs have non-linear brightness and the heavily overdriven ones are typically FAR beyond the point of diminishing returns. In some cases the reduction in power results in basically no visible difference in light output. In some cases it can be argued they’re literally stealing extra power from your electricity bill and using it as an electric heater for no purpose other than to burn out your own light bulbs prematurely so you have to replace them.

    The good news is, like I said, removing one of the responsible resistors instantly solves the design flaw and is usually quite easy even without any special tools or electronics knowledge. BigCliveDotCom calls this “Doobying” the bulbs after the Dubai bulbs that were mentioned in other comments. If you watch some of his videos about LED bulbs you should be able to see the pattern of which resistors to remove, if they are on the board they will basically always be right next to each other and relatively small values (typically in the 20 ohms to 200 ohms range). The only modification I make to his procedure is that I prefer to remove the HIGHER value of the two resistors instead of the lower one, which results in perhaps somewhat less lifetime preservation (still much more than the original setting) and less power savings, but more brightness, and is usually adequately good for my purposes. I also use sturdy tweezers to remove the resistor instead of a screwdriver which seems to me that it would have a higher risk of collateral damage.

    Is it a lot of work for a single light bulb? Kind of, yes. But once you get it done a bunch of times, you’ll probably rarely have to do it again, as these bulbs last almost forever. In fact, I have yet to have one actually fail, I am mostly just replacing the occasional old unmodified LED bulb from time to time.

    This will not work with dimmable bulbs or certain fancy high end bulbs. Also some are much, much easier to modify than others. Clive calls the ones that are relatively easy “hackable” and it’s really a crapshoot to find them. Some have covers/bulbs/diffusers that are nearly impossible to remove without catastrophic damage to the bulb and/or your hands. Others simply use a different circuit design that doesn’t have resistors. Some only have a single resistor, meaning to change the value you need to solder a new one in its place. In my experience, the bargain-basement, junkiest, least reliable bulbs tend to be the easiest to hack this way and often skimp on things like “gluing the lens on” so it’s easy to get off. But you’ll have to experiment to find a brand and style that works well for this.



  • Keep the gray plastic. Remove black clip around the vertical wheel post in the gray plastic. Remove wheel and wheel post. Buy new wheel. Installl new wheel. It will be easier to find a new wheel once you have the old wheel out so you can take measurements. but it’s likely something pretty standard, off-the-shelf. Wheels are something that companies buy, they rarely build them themselves. They typically come as a castoring assembly with wheel, axle, spindle, and attachment post in a variety of common sizes and with a dizzying variety of actual wheels.


  • a) Forecasts are very resource-intensive, they are performed on a specific schedule using a computational forecast model. Updating the predictions would require inputting new data and running the model again, and by the time they do that, the next forecast will already be out.

    b) Do they know it’s wrong? Where did you get the temperature? From an official weather station? If not, there is no reason to imagine that someone is noticing that this one particular model run was wrong in one particular spot across the whole country and trying to fix it in real time.

    c) If you did get the current temperature from an official weather station, that IS your update for it. Real time data from official weather stations is always going to trump the forecast model. What would be the point of updating the forecast when the current measured data from the weather station is now available? That’s like driving down the highway and saying “I was predicting my speed would be close to 65mph, but due to the heavy traffic I’m seeing today, I’m going to re-estimate my speed to be 45mph” when you have a perfectly accurate speedometer right in front of you telling you exactly what speed you are going at all times. Forecasts are only useful for the future, and they can be wrong.


  • They’re only lying as long as people can continue to over and over find their way around the obstacles they place in the way, and it gets harder all the time. They have more money and more resources and more organization than the hackers trying to defeat them, they’re winning the war of attrition. We may be able to make small breakthroughs here and there, but overall we continue to lose more and more territory, because the amount of effort is disproportionate to the goals. Most of what’s left of the custom ROM community has given up on the losing battle with manufacturers and providers and changed focus to the various freephones but even they have their own troubles and are fragmented and short-lived. Between carriers, manufacturers, and content providers the whole mobile ecosystem is designed to be impenetrable. It is intentionally a fortress full of deadly traps and open source supporters have no hope to breach it anytime soon.


  • It’s possible but not likely or common. Glass is stronger than most people give it credit for. Most “hollywood” glass is actually panes of sugar. You could certainly arrange things so that the gun’s pressure wave has a good chance of stressing and breaking glass, but it would take special preparations and effort and the gun would probably have to be very close to the glass. It’s almost unheard of for it to happen normally unless you specifically shoot at the glass.

    Someone like mythbusters could probably test this pretty effectively, but based on my experience around guns and glass, I suspect they’d come to the same conclusion.

    A not directly related but still interesting video was done by the slowmo guys on youtube


  • It’s veeeeery not standard in Canada. I use it on my phone and most people who see it on the lockscreen treat me like I’m an alien, and it’s about a 50/50 mix of people who simply think 24 hour time is weird (but at least recognize it) vs. people who seem genuinely baffled by the digits they see appearing on my phone and don’t even seem to recognize it as a time at all.


  • No good reason, just historical inertia and resistance to change. People stick to what they’re familiar with, either the imperial system or to common metric units. Making a “metric ton” similar in size to an “imperial ton” arguably helped make it easier for some people to transition to metric.

    Megagram is a perfectly cromulent unit, just like “cromulent” is a perfectly cromulent word, but people still don’t use it very often. That’s just how language works. People use the words they prefer, and those words become common. Maybe if you start describing things in megagrams other people will also start doing it and it will become a common part of the language. Language is organic like that, there isn’t anyone making decisions on its behalf, although some people and organizations try.



  • If you can prove beyond any reasonable doubt that someone is ignorant of facts, and then sure you can call it obvious and good. But when nobody can agree what is reasonable, why is your perspective of good the one everyone must follow? It’s not always obvious. Don’t pretend it is. And things that are reasonable and obvious to you aren’t necessarily reasonable and obvious to others. You aren’t willing to embrace the diversity of human experience and opinion, so you won’t get the benefits of that diversity. Just because someone else has a different idea doesn’t make it wrong. If you think literally every idea that isn’t exactly the same as yours is wrong, then we’re wasting our time here anyway.

    So again, why is your path the one we’re picking? Even if I do agree with it, I am not willing to agree to it blindly, I want to know why we’re supposed to follow your advice/instructions/demands. At gunpoint or otherwise. And that’s why I’ll never follow a totalitarian, because totalitarians never have to explain themselves, and generally won’t. I hope you brought enough bullets if that’s your plan.


  • Musk is the richest man on Earth, give or take a few billion here or there. He can keep it running as long as he wants. It’s nothing but a toy to him. The problem will start when he finally gets bored of it, because he has already broken it to the point that nobody else will want it. He has killed it, it’s just not dead yet as long as he keeps swinging it around and paying its bills. But one day he’ll stop doing that, maybe once he finds a new, shinier toy. We just don’t know when.




  • I’d argue against that. For one thing it is impossible to imagine a situation where there is no change in the gravitational gradient across your body over time. Your orbiting a black hole situation is a perfect example of a situation where the gradient alone would tear you apart. The conditions you’ve specified are tautological. There’s no way to maintain a zero gravitational gradient while also simultaneously having extremely high gravitational field. The two are mutually exclusive in any conceivable scenario.

    It’s like saying a human being in a hypersonic wind stream won’t necessarily hurt you, burn you alive and rip you to pieces (not necessarily in that order) as long as there is no turbulence and you have a sufficient boundary layer – but you’re a non-aerodynamic human body in a hypersonic wind stream, so of course there will be turbulence and the boundary layer will not protect you at all, you’re going to die, basically instantly.


  • Call the local fire department non-emergency number and ask if they can schedule a visit to inspect your fire alarms and provide recommendations on the situation. The fire department is genuinely interested in your safety, because it’s also important for their safety so they don’t have to come rescue you. If anything is a fire hazard, the professionals can explain why and explain how to fix it. But they’ll probably say “WTF” because the landlord is most likely just being a fuckface, as landlords do. Assuming the latter, ask them if you get the “WTF” in writing so you can wave it in the landlord’s face when you tell them to fuck off and die.



  • It does not need to go to earth. Take a 1.5v alkaline battery, connect one end of the battery to the other end – a large amount of current flows, no earth involved. The electric charge that a neuron can produce is basically like tiny cells of a biochemical battery. The problem is unlike a useful battery, the voltage difference between all the individual cells is not (and realistically cannot be) carefully organized in a series or parallel path from positive to negative, instead all the positive and negative connections are jumbled together into a complex network, meaning there’s no way of getting billions of volts out of it. It’s just not wired that way.

    Theoretically if you carefully constructed a series of hundreds of billions of neurons connected end-to-end-to-end in the right pattern you might end up with billions of volts (although end-to-end it would probably be the size of the solar system, so the billions of volts potential wouldn’t seem so impressive anymore on an astronomical scale) and you probably can’t pack it your neural-battery into a small space without the neuron’s insulator (myelin sheath) from breaking down and shorting out that voltage. Also it wouldn’t really be a brain anymore at that point. The complex maze of connections are what makes the thinking happen. If you make them all single-connected you’ve basically just got a really big, low capacity and relatively inefficient battery compared to better chemistries.

    Flowing all that current at once will certainly create a lot of heat though, you’re right about that. That heat is normally heatsinked by the intracranial fluids and conducted away by the relatively rapid bloodflow through around the brain to be dissipated in the skin and lungs. The brain is basically liquid-cooled and it’s a very efficient and tightly regulated system that rarely has issues. Such a high neutral output would probably overwhelm even the relatively robust cooling that bloodflow provides, though, leading to a condition called brain hyperthermia, which is part of the reason drugs like methamphetamine can be dangerous or fatal, as it can result in cell death, and in this case, probably brain death and overall death.