I've read that glass is not really a solid, and that it flows very gradually over time, so older windows are distorted and thicker at the bottom. But then I've also read that this is a myth, that glass is a stable amorphous solid, and that any imperfections in older glass are simply due to a less precise method of fabrication than modern glass.
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I read the thing about glass, too.
Interesting stuff.
I had thought that the thickness of panes of stained glass (or regular glass) are thinner at the top after a century or so than they are at the bottom.
Manufacturing could account for that only if the glaziers purposely fit the glass so that the thicker parts were on the bottom of how the window would eventually be oriented.
Or maybe no one looked at more than a few panes and then assumed they were typical when they were just randomly oriented thin-side-up and now someone has studied more glass?
It's good that they finally got it on video, but it's old-hat to those of who have a prostate the size of an Idaho potato.
I first read this as "pitch" as in "sound".
It can be pretty viscous too
The non-laminar flow of viscous liquids through the extraction funnel stopcock should assist madawaskan's understanding of the Bernoulli effect.
That's why we rotate the windows every year.
In some old windows glaziers very well may have used glass that was already thin on one end instead of rejecting it because glass was so expensive, and put the thin end where it wouldn't have to support the weight of the whole pane.
Glass is an amorphous material, which means there is no regular arrangement of its molecules. Amorphous materials have the properties of solids; they have definite shape and volume. They also diffuse slowly. Thus, in many respects they resemble liquids that flow very slowly at room temperature.
Materials like metals, on the other hand, have a crystalline structure where the atoms are neatly arranged in a 3-D array or lattice.
Did I mention I was taking an online online course on materials.
We need window bras.
Did they work out the mach number.
El Pollo
******
The non-laminar flow
I want to translate that to turbulence but that can't be right.
The friction of the walls of the funnel slow that part down, and the center area of the fluid drops faster...
Son of a blank , blank I still get freaked out about sailing---I still see wind as pushing the sail--and trying to sail while considering that it is suction--moving you forward freaks me the hell out!
I probably have that wrong--I haven't been sailing more than 20 times and people know I am a klutz--so you know.
Although the crystalline structure of metals does move about in response to pressure or heat. "Working" the metal messes it all up, which is why a metal worker will repeatedly anneal the metal between working. Heat allows the metal to recrystalize.
Rock also morphs in relation to heat and pressure without melting. This doesn't happen at the conditions on the Earth's surface but that's just a happy chance.
The sail throws air backwards, which does the work. The low pressure ahead of the sail is just part of the solution of the Navier Stokes equations for the airflow. It throws the air ahead of the sail backwards as well as the air in back of the sail, hence the low pressure ahead of the sail. It sucks air backwards, if you want to look at it that way.
The shapes involved are just to result in the most efficient air throwing.
The bernoulli effect is a red herring. It's an effect, not a cause. Air moves faster in a low pressure area because it ran down a pressure gradient to get there, not vice versa.
They've been poisoning boys' minds with the bernoulli effect ever since airplanes were invented.
Thanks rh for the input.
@ madawaskan, I've been told that supposedly this is her best novel:
We the Living is the first novel published by the Russian-American novelist Ayn Rand. It was also Rand's first statement against communism. First published in 1936, it is a story of life in post-revolutionary Russia. Rand observes in the foreword to this book that We the Living was the closest she would ever come to writing an autobiography. Her working title for the novel had been Airtight. We the Living was first completed in 1934, but, despite support from H. L. Mencken,[1] who deemed it "a really excellent piece of work,"...
I think it is her best work. I have read them all. It reminds me of “Dr. Zhivago”.
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