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That the cell phone networks went down is a criminal negligence and should be prosecuted.


When we see power outages in Texas the cell networks will stay up for about 5 minutes until everyone switches from WiFi to 5G for their internet and crashes the network.


Yeah, I can't reach out their website from Denmark for some unknown reasons. On top of that the most recent update of their RSS feed server fxxxd up my news reader so I'm even less inclined to see whatever they do because it looks like they're not very competent technology-wise.


I was using Metrowerks C++ compiler suite to develop code for Dragonball (68000) embedded system 22 years ago!


> No. What causes lift is the differential in pressure between the top and the bottom surface of the wing.

How do you explain airplanes that can fly with wing with symmetrical cross-section profile?

How do you explain airplanes flying upside-down?


To create lift with a symmetrical airfoil, you are going to need a non-zero angle of attack. You can see the effect of a varying angle of attack on a symmetric NACA 0012 airfoil here [0].

The following plot shows the pressure distribution over a wing at 3 different angles of attack [1]. As you can see from the first plot, some lift is created at -8 degrees AOA, but clearly a lot less than the +10 AOA example, as that airfoil is optimized for positive angles of attack.

[0] https://www.youtube.com/watch?v=8uMlDL9HiaY

[1] http://avstop.com/AC/FlightTraingHandbook/imagese0.jpg


Explanation based on Bernoulli effect requires longer path of air taking on top than on the bottom of the airfoil to create speed/pressure difference. With symmetrical airfoil both paths are the same regardless of the angle of attack. So when you mention AoA you implicitly lead to the explanation that lift, in majority, is not based on the Bernoulli effect.

I've read excellent article debunking the Bernoulli effect and lift many years ago, I'm not sure I can find it again...


Explanations based on the Bernoulli effect are trying to explain a speed differential by pretending that two particles that were separated on the leading-edge of an airfoil, to then travel one above the airfoil, one below, would then rejoin at the trailing edge of the airfoil. And so, if you were to change the upper-camber of the airfoil, the flow on the upper part would need to accelerate to be able to join the trailing edge at the same time. And that would create a lower pressure, therefore lift.

The nonsensical part of this model is that a particle on an upper streamline has anything to do with a particle on a lower streamline and that it is trying to keep up with it. Not so of course.

But the lift created by a pressure difference due to a locally faster flow still holds.

> So when you mention AoA you implicitly lead to the explanation that lift, in majority, is not based on the Bernoulli effect.

For a NACA 0012, you'll need an AoA, to have a faster flow on the upper part of your airfoil, as it it symmetric. Other airfoils are perfectly fine creating lift at 0 AoA.


The Bernoulli effect only contributes to making wings more efficient. It isn’t fundamentally why lift occurs.

You can make almost anything fly if you have enough power and a tail. But how efficient will it be? Not as efficient as an airfoil that takes advantage of all the fluid motion properties.


I think you wanted to respond to the parent comment. My questions have been a lead to debunk myth that the major contributor to the lift is the Bernoulli effect.


> How do you explain airplanes that can fly with wing with symmetrical cross-section profile?

> How do you explain airplanes flying upside-down?

Angle of attack is what causes lift. If you have a surface angled against the relative wind, it will produce lift.


I know all of that. I wanted to provoke parent commenter to let them see that the Bernoulli effect doesn't explain my two examples.


"The main goal is to make everything as easy as possible, says Kristina Behr, Google’s VP of product management for the Workspace collaboration apps."

Looking up Kristina Behr on LI it looks like she jumped ships from MS to Google slightly over a year ago. At MS' last post she's been responsible for "Empowering frontline workers to achieve more with comms-first productivity and workflow solutions" listing following achievements:

* Introducing Microsoft Teams Premium, the better way to meet | Microsoft 365 Blog

* Microsoft Teams for frontline workers: What's Live and Coming Soon

and so on...

Yeah, I'll pass :)


Regular LEGO sets are not intended for small kids, Duplo sets are. Every LEGO set comes with suggested age range or suggested minimum age on the box.


"The image was captured by the small baseball-sized robot called Sora-Q that was ejected from Slim moments before touchdown last Saturday."

https://www.bbc.com/news/science-environment-68091389


I'm really not sure about the humor. Take a look at "Every Frame a Painting: Edgar Wright - How to Do Visual Comedy":

https://www.youtube.com/watch?v=3FOzD4Sfgag



Sharp edges are also not allowed in most European countries.


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